Problem Charging Aux Batteries with Smart Charger

[D4206]

Hi, I'm in need of some advice. I have recently installed a Traxide D4-5U kit into my D4, with an additional third 80AH Thumper Battery in the back. It all seemed to work fine when charging from the cars alternator, however when I plugged a smart Charger into the Anderson plug at the back of the car to charge the batteries after they had been running a fridge for a day I noticed that the CTEK Charger (Multi XS 7000) did not complete its full cycle...in fact in the morning the Thumper battery had been cooked! I was under the impression that all batteries in the car could be charged from the rear Anderson plug with the Traxide Kit....obviously I'm wrong and have found out the hard way..by buggering up a battery.

How does one go about re-charging the (connected) batteries in the car from a 240V charger without damaging the batteries? Surely they do not have to be disconnected from each other and individually charged?

Cheers,
Bill

[austastar]

Hi,
I charge both batteries by connecting the charger across the starter battery when I have plenty of time and mains power available.

In the bush I usually only connect across the Aux battery. The starter should by now have disconnected the two (traxide SC80), and the solar panel is used if solar gain is possible, or later in the afternoon I will fire up the generator to power the charger (multistage)

I'm curious as to how a charger could cook a battery, unless the charger was faulty.

Cheers

[alien]

May I suggest to ring Tim and ask him what works with his kit.
I run his gear but with a different set up so what works for me wont work for you.

[Tombie]

Something was wrong with the Thumper or Charger to cook it with a simple charge.

What mode was the charger in?

[D4206]

Something was wrong with the Thumper or Charger to cook it with a simple charge.

What mode was the charger in?

Mmmm.... thumper has been fine up till now.....the charger was in "normal" mode & it normally indicates charging stage/levels via 4 led lights. Only got up to led 2. I'm wondering if the charger is not capable of charging three connected batteries?

[Tombie]

The MXS 7.0 can charge up to 225Ah of batteries in its design spec.

If the charger was in Power Supply mode it could potentially harm the Batteries but that's after a long time.

How olds your Thumper and how discharged was it? Was it running any devices at the time?

[D4206]

The MXS 7.0 can charge up to 225Ah of batteries in its design spec.

If the charger was in Power Supply mode it could potentially harm the Batteries but that's after a long time.

How olds your Thumper and how discharged was it? Was it running any devices at the time?

The charger was in charge mode, not power supply mode.

The thumper was about 3 yrs old.

Fridge in car was off.

[BobD]

There is nothing magic about the Traxide system. All it does is disconnect the starter battery from the aux battery when the voltage drops enough. The rear Anderson plug is just a direct connection to the aux battery. If you apply a voltage to the Anderson plug it just applies that voltage minus losses in the wiring to anything connected to that circuit. It will also apply voltage to the starter battery if they are connected at the time.

I'm not sure what you think is happening but that is all it is. The Traxide system won't affect anything that you plug into it and can't damage anything by itself. There is probably either a problem with the way you have plugged the Thumper into the system or the CTEK is faulty. Failing that, there could be a problem with dissimilar battery types being connected together. The starter battery is a calcium battery which can be charged at a higher voltage than AGM or conventional batteries but I don't know what your other two batteries are. Perhaps the Thumper didn't like the voltage that the car was providing to charge the starter battery and that was what cooked it. The CTEK wouldn't charge because the battery was already cooked.

The Optima AGM battery that is usually used as the aux battery in D4's is more robust then most AGM batteries and doesn't mind high charge rates and voltages and is perfectly suited to the D4. It is possible that the thumper is not so suitable but you haven't provided any info on how it is connected to the system or what type of battery it has that I can see. Is it connected via the 12V plugs in the rear that are part of the Traxide kit?

What do you mean by a cooked battery? Is it boiling, not holding charge, low voltage or what?

[D4206]

There is nothing magic about the Traxide system. All it does is disconnect the starter battery from the aux battery when the voltage drops enough. The rear Anderson plug is just a direct connection to the aux battery. If you apply a voltage to the Anderson plug it just applies that voltage minus losses in the wiring to anything connected to that circuit. It will also apply voltage to the starter battery if they are connected at the time.

I'm not sure what you think is happening but that is all it is. The Traxide system won't affect anything that you plug into it and can't damage anything by itself. There is probably either a problem with the way you have plugged the Thumper into the system or the CTEK is faulty. Failing that, there could be a problem with dissimilar battery types being connected together. The starter battery is a calcium battery which can be charged at a higher voltage than AGM or conventional batteries but I don't know what your other two batteries are. Perhaps the Thumper didn't like the voltage that the car was providing to charge the starter battery and that was what cooked it. The CTEK wouldn't charge because the battery was already cooked.

The Optima AGM battery that is usually used as the aux battery in D4's is more robust then most AGM batteries and doesn't mind high charge rates and voltages and is perfectly suited to the D4. It is possible that the thumper is not so suitable but you haven't provided any info on how it is connected to the system or what type of battery it has that I can see. Is it connected via the 12V plugs in the rear that are part of the Traxide kit?

What do you mean by a cooked battery? Is it boiling, not holding charge, low voltage or what?

Thanks for the detailed advice. Your explanation at the beginning is what I expected to occur, ie, plug charger into Anderson plug at back of car and all three batteries would charge.(assuming start battery was still connected via the traxide controller).

The Ctek charger has in the past successfully charged the Thumper on its own.

Voltage whilst charging was just over 14v.

The thumper is connected via Anderson plug into the Traxide kit. (The wiring was modified by Tim to allow for the 3rd battery in the car)

This morning the thumper was very hot and smelly so I disconnected it from the system. Took the top off and the batteries inside the housing are swollen..voltage indicator is now showing 4-5V, so I assume a couple of cells are now stuffed. Whilst it was charging I noticed the amps input was low at around 1-2A. Normally it would start a lot higher than that & reduce over time.

I'm assuming the cells inside the thumper are AGM, similar to the Optima.

Based on your comments it seems that perhaps the thumper was on the way out?

I'm a bit reluctant to plug the charger back into the rear Anderson plug with just the optima and start battery. Any way of testing the charger for faults, in case it was the cause?

[Eevo]

sounds like the battery dropped a cell.


to test the charger, find a battery thats not in the car and charge it

[BobD]

The AGMs in the Thumper would not be the same as Optima because they are special. They are AGM but spiral wound instead of flat panels and much more robust with less problems on corrugations etc.

Bit hard to check the charger because I don't think it will work unless connected to a battery with sufficient voltage to get it going.

Did you notice it being the normal fairly hot temperature that the CTEKs run at or was it cold or really hot? Was the 14V still happening when you disconnected it or just when it started charging?

I would expect that the aux battery would have been feeding high current into the Thumper if it was hot and smelly so check that battery voltage first, if you haven't already. A 7A charger would probably not be able to provide all that much energy to the battery so perhaps it was the other battery that did the damage.

[drivesafe]

Hi D4206, from what you have posted, there are two possibilities, one has been covered by a few posters, and that is that the thumper battery was either stuffed when you connected the charger or failed while charging it.


In this case,because the charger is only a small current charger, the thumper battery simply pulled the charger and the other batteries down.


The other possibility is that the charger went over voltage ( I don’t thing this is the case ) and as the USI-160 has over voltage protection, it simply turned off when the voltage got too high.


Again, the first suggestion is most likely the case.


PS does the 4206 in your handle stand for anything specific?

[BobD]

Tim,

If the USI 160 turned off it just isolates the aux batteries from the starter battery so wouldn't affect the Thumper unless he also has a USI 160 between the two aux batteries??

[drivesafe]

Yep, I agree Bob, and that’s why I posted that the thumper battery is more than likely to problem.

[D4206]

Hi D4206, from what you have posted, there are two possibilities, one has been covered by a few posters, and that is that the thumper battery was either stuffed when you connected the charger or failed while charging it.


In this case,because the charger is only a small current charger, the thumper battery simply pulled the charger and the other batteries down.


The other possibility is that the charger went over voltage ( I don’t thing this is the case ) and as the USI-160 has over voltage protection, it simply turned off when the voltage got too high.


Again, the first suggestion is most likely the case.


PS does the 4206 in your handle stand for anything specific?

Thanks for the comments Tim.

Seems as though the thumper may have been the problem.

As far as I know the Optima is still ok. (It's only a few months old), so hopefully hasn't been damaged.

Would you suggest a higher output smart charger be used rather than the Ctek?

Can I replace it with another AGM battery...ie not another Optima, just a deep cycle AGM? The incompatibility question mentioned in a previous comment concerns me.

D4 =Disco, 206=house number.

Cheers,
Bill

[drivesafe]

Hi again Bill and no. The 7 amp charger is ideal for what you are doing.


It is actually healthier for lead acid batteries to be charged with low currents rather than high currents.


So again, stick with the charger you have, and your batteries will love you for doing so.

[Tombie]

Just to help.. you can buy replacement batteries for the Thumper - $62ea
They are just an alarm battery BTW...

And do not be worried by the old "mixed battery type" statement... that's not an issue in these vehicles (LiThium excepted).

The AGM charging profile is higher than Normal mode (for Ca/Ca, MF and Gel) so you were running lower not higher...

https://www.aulro.com/afvb/images/imported/2017/03/641.jpg

[BMKal]

C-Tek shouldn't have any problems at all charging this set-up if batteries are in good nick. [wink11]

I have almost the identical set-up in my D4. Traxide system installed, with Optima yellow top under the bonnet, and an Engel battery pack very similar to the Thumper in the back running the fridge. I plug a C-Tek charger or an 80W solar panel into the Anderson plug on the back of the vehicle every two or three months to bring everything back up to fully charged, and have never had a problem.

Coincidentally, I also have a stuffed Thumper out in the shed. It has never been in the D4, and was last used two or three years ago. I recently went to use it and it was dead flat. Pulled the top off and found a loose connection inside the box on the negative terminal post - fixed that, but it will not take a charge. I haven't checked yet if one or all four of the cells inside the box are stuffed - but I have been thinking about buying replacement/s as required. Thanks Mike - I had not got around to looking up the price of replacement cells yet. [biggrin]

[cjc_td5]

I have cooked thumper batteries in the past too I think from too high charge current. If the batteries are discharged they can try to take more current than they can handle and the batteries inside will get hot and warp. I installed some ventilation holes into my thumper casing to give the batteries inside some ventilation. I think to charge the thumper AGM batteries you need to limit the current to less than 4A?

The batteries inside are just regular AGM batteries available from Battery World et al...

[D4206]

Thank you very much for all the responses....much appreciated [emoji16][emoji106]

[go-disco4]

Rather than start a new thread I have a related question regarding charging with C Tek and Traxide.

I have 2.7 L D4. 90 AH starter battery and a 55 AH Optima yellow top and a SC 80.

This gives a total of 145 AH.

The C Tek MXS 5.0 is meant to charge up to 110 AH batteries but able to maintain 160 AH batteries.

IS the CTEK MXS 5.0 able to charge this set up or is it under power?

The reason why I asked is that I went to Dargo this long weekend and after a 5 -6 hour drive, the Voltage for both batteries were 12.6 V the next morning after resting the car overnight. The next day, after driving the tracks for about the same hours ( 5 - 6), the batteries again registered 12.6 V the next morning and the same when I returned to Melbourne.

After I arrive back in Melbourne, I put the CTEK on the car the next morning and after charging it for nearly 12 hours, the following morning it only measured 12.48 V. The V was 12.6 V before I put the charger on. I thought it would at least maintain the 12.6 V rather than letting it drop.

I cannot understand this.

Is the car alternator more efficient than the CTEK?

Why did the Voltage drop when it was being charge?

Many thanks for your thoughts

GD-4

[DiscoMick]

12.6 is fully charged (6x2.1).
Which battery was the C -Tek charging - the starting or second battery?
If batteries of different sizes are connected they may equalize at the capacity of the smallest battery, so the larger one may not be fully charged.

[BobD]

The alternator will provide far more power than a 5A CTEK. There is no comparison! The only reason for charging with the CTEK is if you are doing very short drives and the battery is not being fully charged in the time that you are driving. With 5A it takes 1 hour to provide 5AH (ignoring the battery charging inefficiency) so you can see how many hours it will take to charge a high AH set of batteries. The alternator will be far quicker to charge them when the engine is running.

[laughto]

The alternator will provide far more power than a 5A CTEK. There is no comparison! The only reason for charging with the CTEK is if you are doing very short drives and the battery is not being fully charged in the time that you are driving. With 5A it takes 1 hour to provide 1AH (ignoring the battery charging inefficiency) so you can see how many hours it will take to charge a high AH set of batteries.

Umm, can you explain the charging rate here. To my simplistic uneducated mind and ignoring all charging and battery inefficiencies, I would have thought that if you needed to charge a battery with 50Ah with a 5A charger, then it would take approximately 50/5 = 10 hours. The way I am reading your calculation, it would take 50 x 1 = 50 hours. What am I missing?

[drivesafe]

Hi laughto and I think Bob might be relating to the fact the batteries were already at 95% SoC and as such, they would not draw more than 1 amp from any charger.


The charger would have gone into FLOAT mode very shortly after it was connected to the near fully charged batteries.


As such, it would drop the applied voltage down to something like 13.5v.


Whereas, as the alternator charges at a constant higher voltage all the time, the batteries would be maintained at a higher state of charger anyway.


Hi GD-4, at 12.65v in the morning, is about as high a state of charge you are going to get and is very good.


I can not make any suggestion for why the lower settled voltage when charging with the battery charger.

This chart will give you some idea of the actual state of charge of your batteries.


​https://www.aulro.com/afvb/images/imported/2017/03/407.jpg

[BobD]

Umm, can you explain the charging rate here. To my simplistic uneducated mind and ignoring all charging and battery inefficiencies, I would have thought that if you needed to charge a battery with 50Ah with a 5A charger, then it would take approximately 50/5 = 10 hours. The way I am reading your calculation, it would take 50 x 1 = 50 hours. What am I missing?

Sorry mate! That was a typo. I got distracted half way through and meant to write 5AH in an hour. You are correct. 10 hours for 50AH when the battery is low. I have corrected the post!

[DiscoMick]

What size is the alternator in these vehicles - 80Ah?
If it is then the alternator is (thinks carefully to avoid usual dodgy maths abilities) 16 times more powerful than a 5Ah battery charger. So it is certainly a lot more powerful.
Returning to my previous question, was the C-Tek connected to the starting or secondary battery, as that could affect the result.
Also, which battery are the readings you are quoting taken from - the starting or second battery?
Your two batteries are significantly different in size.

[DiscoJeffster]

Add 100amps. They're 180A.

[Tombie]

Battery size will have minimal impact on charging...

Don't forget to factor in that regardless of how much current an alternator produces it only provides head room *above* vehicle consumption.. so while the Alternator has a nameplate 16x that of the charger - it may only have 2x the charger output to give - I've seen cases where it's about parity!!!

[go-disco4]

What size is the alternator in these vehicles - 80Ah?
If it is then the alternator is (thinks carefully to avoid usual dodgy maths abilities) 16 times more powerful than a 5Ah battery charger. So it is certainly a lot more powerful.
Returning to my previous question, was the C-Tek connected to the starting or secondary battery, as that could affect the result.
Also, which battery are the readings you are quoting taken from - the starting or second battery?
Your two batteries are significantly different in size.

Hi All,

Thanks for all your comments.

C-TEK connected to Cranking battery. Both battery measured the same voltage. Always the case. Also the charging voltage is the same for both batteries measured at the terminals.

The initial V for both batteries was 12.6 the morning after I got back. Charge it all day and next morning was 12.48. Charge it all day again and the next morning was 12.53. Charge it again and during the FLOAT part of the charging cycle, the CTEK was delivering only 13.06 Volts to both batteries.

Did not check the V the next day.

Thanks

GD-4

PS; Picture of car in Dargo posted in the "Show me..." thread.

[D4206]

A further question regarding charging the start battery and optima via the Anderson plug..... I've connected the Ctek charger to the Anderson plug and checked voltages at both the start battery (14.7v) and Optima battery (12.4v). Does this difference in voltage mean that only the optima is being charged? I thought both batteries would be charged at the same time.

The switch on the controller is away from the led light, which should mean that they are connected? The light is flashing once every couple of seconds.

[D4206]

Forget to mention the traxide controller is the UCI 160.

[DiscoMick]

Hi All,

Thanks for all your comments.

C-TEK connected to Cranking battery. Both battery measured the same voltage. Always the case. Also the charging voltage is the same for both batteries measured at the terminals.

The initial V for both batteries was 12.6 the morning after I got back. Charge it all day and next morning was 12.48. Charge it all day again and the next morning was 12.53. Charge it again and during the FLOAT part of the charging cycle, the CTEK was delivering only 13.06 Volts to both batteries.

Did not check the V the next day.

Thanks

GD-4

PS; Picture of car in Dargo posted in the "Show me..." thread.
OK so you're charging the start battery and that is flowing to the second battery.
The start battery is showing a float charge, but put under load would probably revert to about 12.6-7, which is fully charged.
If two batteries of different sizes are connected the larger battery may only charge to the level of the smaller battery, I believe.
If your battery is showing 12.6 then it is fully charged and should not need charging for at least a week, depending on what is draining it.

[D4206]

A further question regarding charging the start battery and optima via the Anderson plug..... I've connected the Ctek charger to the Anderson plug and checked voltages at both the start battery (14.7v) and Optima battery (12.4v). Does this difference in voltage mean that only the optima is being charged? I thought both batteries would be charged at the same time.

The switch on the controller is away from the led light, which should mean that they are connected? The light is flashing once every couple of seconds.

Correction to the above....the optima is being charged and is showing 14.7v, the start battery is reading 12.4v, To me that would indicate that they are not connected. Why wouldn't they be connected by the controller?

[DiscoMick]

They could be connected but still give different readings.

[drivesafe]

The switch on the controller is away from the led light, which should mean that they are connected? The light is flashing once every couple of seconds.
Hi and if the LED is flashing once every few seconds, then the USI-160 is off.


Try starting your motor and let it run until the LED goes to a solid glow. ( about 15 seconds )


Then you can turn your motor off and the charger will now charge both batteries.

[D4206]

Hi and if the LED is flashing once every few seconds, then the USI-160 is off.


Try starting your motor and let it run until the LED goes to a solid glow. ( about 15 seconds )


Then you can turn your motor off and the charger will now charge both batteries.

Thanks Tim, I'll try this in the morning. When they're both charging should they both show the same voltage?

I'm still trying to understand how the system works. I'm assuming the batteries may have been disconnected because the car had not been used for a day? Ie the time out feature?

[drivesafe]

Thanks Tim, I'll try this in the morning. When they're both charging should they both show the same voltage?

I'm still trying to understand how the system works. I'm assuming the batteries may have been disconnected because the car had not been used for a day? Ie the time out feature?
Yes and it sounds like the USI-160 did TIME-OUT because the cranking battery voltage was still way above the Cut-Out voltage of 12.0v

[D4206]

Yes and it sounds like the USI-160 did TIME-OUT because the cranking battery voltage was still way above the Cut-Out voltage of 12.0v

All good[emoji106] Started the car and waited for the light to go solid as you suggested and now both batteries are charging (via the Ctek plugged into the rear Anderson plug) and reading the same voltage.

Cheers,
Bill

[go-disco4]

Quote : GD4
C-TEK connected to Cranking battery. Both battery measured the same voltage. Always the case. Also the charging voltage is the same for both batteries measured at the terminals.
The initial V for both batteries was 12.6 the morning after I got back. Charge it all day and next morning was 12.48. Charge it all day again and the next morning was 12.53. Charge it again and during the FLOAT part of the charging cycle, the CTEK was delivering only 13.06 Volts to both batteries.
Did not check the V the next day.


OK so you're charging the start battery and that is flowing to the second battery.
The start battery is showing a float charge, but put under load would probably revert to about 12.6-7, which is fully charged.
If two batteries of different sizes are connected the larger battery may only charge to the level of the smaller battery, I believe.
If your battery is showing 12.6 then it is fully charged and should not need charging for at least a week, depending on what is draining it.

Hi again,

Thanks for everyone's comments.

Further help sought.

Following charging the 2 batteries as described above for 3 days last weekend.Today, 5 days later after charging stopped, the optima is 13.0 V (presumably fully charged), but the cranking battery is only 12.26 V.

The LED light is continuously flashing. It continues to flash even if I disconnected the negative leads from the Optima (the SC-80 earth wire remains earthed though).

Questions:

1. I thought flashing LED means that the SC_80 isolated the 2 batteries because the combined V for the 2 batteries have dropped to less than 12.0 V. This is obviously not the case here. So why is it flashing?

2. Why does it flash even when the negative leads are disconnected from the Optima and the 2 batteries are no longer connected?

3. The old SC-80 does not have time out feature I believe. How much current does it does it draw form the cranking battery when connected?

Many thanks again

GD-4

[landoman]

I have some questions based on problems similar to those discussed in this thread

my dual battery set set up is the standard
OEM starter battery ( 90 AH )
Optima yellow top ( 55AH)
Traxide SC 80
Anderson plug at rear connected to Optima yellow top

I have been trying to fully charge my two batteries with a 5 amp 8 phase charger
I left it plugged in to the Anderson plug ( and optima 55 ah battery) most of yesterday and all last night but cannot get past STEP 4 (absorption ) on the charger

This morning I clipped the charger directly to the starter battery and after 4 hours it still has not progressed past the absorption (phase 4)

The SC80 has a solid green light and the voltage on both batteries with the charger on is 14.5
volts ....so the charge is flowing into the starter battery and across to the optima second battery

I have read above that the time to charge my batteries should be
90 AH + 55 AH =145 AH / 5 amps = 29 hours .......is this correct or is my charger too
small for the job ?

Do I need a bigger charger or am I just being impatient and eventually
my charger will eventually get to the float phase ( step 7)

The charger I'm using says (" battery capacity 10-120 ah ....maintainance charge to 200 ah")
given my batteries are 90 ah and 55 ah and the charge flows from one to the other ( either way ) should I be looking at a stronger charger........or again is it just a matter of time for the both batteries to get to the float ( step 7) and pulse ( step 8)

[Tombie]

I’ve had this before. It’s more about the vehicle waking up and pulling that little bit off the top...

I wouldn’t panic at all.

[Tombie]

If it makes you feel all good, I purchased a 25a ctek and that can get on top of them but I’ve found no benefit in doing so...

[drivesafe]

Hi Landoman, as Tombie posted, don’t panic.


Also, forget you math, the charger actually does not work that way.


While the batteries are low, they will draw the full 5 amps from your charger.


But as the batteries get close to a fully charged state, they will draw less current and this may cause your charger to take a much longer time before it decides to go into the float stage.


This is not a problem, just leave your charger on and see how long it takes to go into the float charge.


BTW, if your batteries are in need of a good charge, in other words, if they were in a poor condition, this will cause the charge to stay in the ABSORPTION stage for a long time, while the batteries regain some/all of their lost capacity.


PS a small charger is much better for your batteries than a big one.

[landoman]

Thanks Tombie and Drivesafe ...........
..Yes Druvesafe I suspect the batteries were in pretty poor state of charge as I had run the optima down to very low on a few occasions and only ever charged both batteries via the alternator while driving ......this is the first time I have used a charger to try to get them fully to top charge ........so you reckon just keep my 5 amp charger on then and eventually they will get to float stage ?

[scarry]

Thanks Tombie and Drivesafe ...........
..Yes Druvesafe I suspect the batteries were in pretty poor state of charge as I had run the optima down to very low on a few occasions and only ever charged both batteries via the alternator while driving ......this is the first time I have used a charger to try to get them fully to top charge ........so you reckon just keep my 5 amp charger on then and eventually they will get to float stage ?

I charge my batteries often,with the same charger as yours,as my vehicle sometimes sits around, we have company cars.

I also have the Traxide SC80 D4 Traxide kit.

I find the best way is to charge the batteries separately,and never let them get too low.Mine will often be on float in a few hours,or overnight at the longest.I have never seen it not go to float,as yours is doing.

One of your batteries may be faulty,isolating and charging them separately may be the go,to determine which one is the problem battery.

The easiest way to isolate the batteries is put a switch in the earth wire,running from the SC80.

[Silenceisgolden]

As a battery becomes fully charged, the current it takes from the charger drops. Chargers typically go into float mode by sensing this drop in current This is how the charger determines the correct time to go into float mode. However, in your case you have two batteries each drawing a little current PLUS the current taken by the Traxide unit. Thus the charger never sees a low enough current draw to go into float mode.
As Scary said, isolate the Traxide by removing the earth lead - this will stop the Traxide drawing current and then you should charge each battery separately. There is a risk of over-charging and damaging the batteries if the charger never goes into float mode.

[scarry]

The other thing i forgot to say,is lock the vehicle as well if you can,as it will draw less power from the batteries,it goes to sleep.
Leaving it unlocked it is not asleep,so draws more current from the battery.

This is difficult to do because if the bonnet is open you will have to loop out the bonnet switch to lock the vehicle.

[drivesafe]

Hi again Landoman, if you still have the charger connected and on, try measuring the voltage at both batteries.

This can give you an idea if the batteries are near fully charged or if the voltage is down a bit because something is continually pulling current.

[landoman]

Hi again Landoman, if you still have the charger connected and on, try measuring the voltage at both batteries.

This can give you an idea if the batteries are near fully charged or if the voltage is down a bit because something is continually pulling current.


Ok I left the charger on all of yesterday and all of last night .......the charger is still on
step 4 absorption phase ...it has not gone to float phase

this charger has a recondition mode and that is what I have the charger set on
....it has an extra recondition step 6 before it goes to step 7 float

the voltage on both batteries ( with the charger on and connected ) is 14.5
i have removed the charger now and will let the batterie sit and rest and see what the voltage is after a few hours .

as I am doing this on a defender 110 and the two batteries and SC80 are in that very tight battery box under the passenger seat it's very hard to get at the earth wire on the SC80 to disconnect it
is there another easier way to disconnect the SC80 .....say taking the leads off the terminals ?
If so which leads if not all of them

I could then then try to charge each battery seperatly as suggested and see if I can get either of them to recondition stage 6 or float stage 7 .

appreciate all the advice .....both batteries are less than 2 years old so I'm hopeful they are both still good .

[LRD414]

I have a ctek 5A charger and the typical Traxide setup of crank plus yellowtop connected via SC80. I charge via the rear Anderson or a ctek lead I have installed to the crank battery positive. I never get the issues mentioned and never seperate the batteries. It always gets to float within an overnight charge period. I always lock the vehicle. The batteries have been down to 12.0 on maybe 2 or 3 occasions. So there may be something else going on with yours.

Scott

[landoman]

Perhaps the problems in in the charger ......it's not a Ctek ...but a Chinese brand ...C9005
......8 step smart charger

is your anderson plug at the rear fitted back to your cranking battery or to the optima ?

my anderson plug goes to the optima .......so have tried charging both using that ....and then clipped the the charger directly to my OEM crank .....but no luck

[LRD414]

Anderson direct to Optima and ctek lead direct to crank. I’ve made a ctek to Anderson adapter lead.

Scott

[landoman]

Anderson direct to Optima and ctek lead direct to crank. I’ve made a ctek to Anderson adapter lead.

Scott
So by using the ctek plugged into the anderson you can get both batteries linked via SC80 to go to float .?
......that is ideally what I'm trying to do as I find accessing the batteries directly by removing the seats and battery box cover a bit of a pain.

i want a system that I simply plug my charger into the rear anderson charge up the optima and then flow across to the crank via the SC80 so both batteries go full charge and to float....should that be possible to do .....seems like you can do that with your ctek ...right ?

[LRD414]

So by using the ctek plugged into the anderson you can get both batteries linked via SC80 to go to float .?
Yep exactly.

[landoman]

Yep exactly.
Ok great ....so I now know what I'm trying to achieve is possible ....just got to figure out
why I can't do it ......it's either a battery problem or a charger problem .....it's definitely not the sc 80 as that is working to keep both batteries linked as it should

[drivesafe]

Hi Landoman, just take the negative lead off both negative ( - ) terminals and then connect your battery charger to one battery at a time, and see if it goes into float mode.

If you can bypass the recondition mode, do so. Long recharge periods have the same effect as recondition modes but long periods in recondition mode can harm batteries.

[landoman]

Hi Landoman, just take the negative lead off both negative ( - ) terminals and then connect your battery charger to one battery at a time, and see if it goes into float mode.

If you can bypass the recondition mode, do so. Long recharge periods have the same effect as recondition modes but long periods in recondition mode can harm batteries.

Ok I can by pass the recon mode so will do that

I have a negative Lead on the crank ....and a negative lead that joins the two batteries
do I take off the negative lead from the crank .....AND the joining negative lead from both batteries negative terminals

sorry ........but this is a bit confusing .....

i have also read the instructions on my 8 phase charger ( always a good idea )
it has different instructions for " separated lead acid battery " and "vechicle mounted lead acid battery

for "separated " it say to put red clamp to positive pole and black clamp to negative pole

for " vehicle mounted " it says red clamp to positive pole and black clamp to chassis
......and ........."if the battery's pos pole is grounded then connect black clamp to negative pole and RED CLAMP TO VECHICLE CHASSIS ? ..........does this sound strange ?

4 hours after I removed the charger both batteries are now at 12.67.....

[drivesafe]

Hi Landoman, and it can be a bit strange if you are not use to doing this but just remove the negative ( - ) terminal battery clamps off both batteries.


It does not matter if the two clamps are still connected in some way, as they are now off both batteries, so both batteries are totally isolated from one another and from your vehicle.


Next, connect the battery charger clamps directly to the battery terminals, of the battery your are going to charge.


Job done.

BTW, with both batteries at 12.67v, they are filly charged but may still require conditioning, so still try your charger on each battery and see how long it takes to go into float.

[Aussie Jeepster]

Hi and if the LED is flashing once every few seconds, then the USI-160 is off.


Try starting your motor and let it run until the LED goes to a solid glow. ( about 15 seconds )


Then you can turn your motor off and the charger will now charge both batteries.

So if I am out in the mulga, and I want to plug my solar panel into my Traxide system via the rear/towbar Anderson plug, I need to run the engine first to make sure the led is a solid glow, THEN connect the panel.
I take it I can't just plug the panel in sometime after I've set up camp?????

[scarry]

Thats why i don't charge from the rear anderson plug,if the plug is connected to the Optima auxiliary battery,which they normally are.

If the batteries are isolated,by the SC80, for what ever reason,no charge will go into the start battery,as the SC80 switches depending on start battery voltage only.

To answer your question,yes you can do that,as long as the voltage does not drop below the SC80 cut out voltage setting,once the motor is turned off.

I have a Ctek adapter permanently wired to the start battery,pokes out of the plastic battery cover, so it is easy to get to,and use the Ctek clamps on the Optima,depending which battery/batteries i want to charge.

And the other issue with the rear plug is,SWMBO may get in and drive away,where with the bonnet open,well,she may think before going any where.[tonguewink]

[landoman]

Ok chaps we are making progress with my problem

I disconnected the negative cables from both batteries so they are separated

then hooked up the charger ( set to normal car battery mode ) to the crank battery .....30 mins later it goes to phase 7 ...float

I then switched the charger ( now set to AGM mode ) over to the optima and about 30 mins later it also goes to float

so what should I try now ....re hook the two batteries together and see if I can get them both
to go to float ...and which battery should I hook up to given the crank is a normal wet battery
and the optima is a AGM and my charger has a mode for each ? .....I think the charging voltage for the agm mode on the charger is higher ( 14.7) than the normal capacity mode (14.4)

[drivesafe]

Hi again Landoman, first off, you can leave your charger set to anything but CALCIUM mode, if your charger has that setting.

Next, as you have suggested, connect up your batteries as normal, and then try charging them with your charger connected to the cranking battery.

[cjc_td5]

Hey Drivesafe, just confirming that the SC80 will allow current to flow back through the unit from auxillary to main battery??

[drivesafe]

Hi Chris, if it is a first generation SC80 isolator, then while the voltage is above 12.0v, current will flow in either direction.

Current will flow from the highest charged battery to the lower charged battery, regardless of whether the cranking battery or the auxiliary battery is the highest charged.

With the new Second Generation SC80 isolators ( all SC80 units sold after April 1, last year ) will operate the same as above, but if a new SC80 has either Timedout or the common voltage has dropped bellow 12.0v and the isolator has turned off, then if a charge is applied to the auxiliary battery, once this voltage rises above 13.2v, the SC80 ( or a DT90 ) will turn on, allowing the cranking battery to be charged as well.

[cjc_td5]

Hi Chris, if it is a first generation SC80 isolator, then while the voltage is above 12.0v, current will flow in either direction.

Current will flow from the highest charged battery to the lower charged battery, regardless of whether the cranking battery or the auxiliary battery is the highest charged.

With the new Second Generation SC80 isolators ( all SC80 units sold after April 1, last year ) will operate the same as above, but if a new SC80 has either Timedout or the common voltage has dropped bellow 12.0v and the isolator has turned off, then if a charge is applied to the auxiliary battery, once this voltage rises above 13.2v, the SC80 ( or a DT90 ) will turn on, allowing the cranking battery to be charged as well.
Thanks. Mine will be an older version so as long as the batteries are linked (solid light) then I can charge either battery and it will cross link and charge the other battery also.
Thanks,
Chris.

[landoman]

Hi again Landoman, first off, you can leave your charger set to anything but CALCIUM mode, if your charger has that setting.

Next, as you have suggested, connect up your batteries as normal, and then try charging them with your charger connected to the cranking battery.


Ok reconnected the two batteries the SC80 was turned off ( blinking light ) so started the engine and it came on ( solid green light ) and put the charger on the cranking battery and in a few minutes it went to float

I then switched the charger to the optima and again after 5 -10 mins it also went to float

now here is the thing ...I then plugged in the charger to the anderson plug at the rear ( which
goes to the optima via 8 AWG cable ...and it's seems stuck on phase 4 absorption ....been like that for about 30 mins now ....the voltage at both batteries is 14.69 coming From the charger at the anderson plug at the rear . The charger is set at AGM mode which according to the charger manual charges at 14.7 volts

so what can I conclude from all this ?

[drivesafe]

While I would expect it might eventually go into float mode, but because of the voltage drop caused by the 8B&S cable and possibly some bad connections causing more voltage drop, it may never go into float mode.

You could experiment with just charging the auxiliary battery.

To do this, again, disconnect the two negative battery clamps for a minute or so and then reconnect the clamps but don’t start your motor, just connect your charger to the Anderson plug and see if it can go into float while charging just one battery.

[landoman]

While I would expect it might eventually go into float mode, but because of the voltage drop caused by the 8B&S cable and possibly some bad connections causing more voltage drop, it may never go into float mode.

You could experiment with just charging the auxiliary battery.

To do this, again, disconnect the two negative battery clamps for a minute or so and then reconnect the clamps but don’t start your motor, just connect your charger to the Anderson plug and see if it can go into float while charging just one battery.


Ok so it looks like we have a win .......I disconnected the charger from the anderson plug
and put it back on to the optima ....after a short while it went into float ......so I took it back to the anderson plug left it connected ....and finally it is in float with both batteries connected
Via the SC80 and the charge coming from the anderson plug at the back .........Hooray !!

So can I conclude that given both batteries connected together have gone to float that they are both ok .....???

and yes Tim perhaps the 8B&S cable may be making the charge harder to get through from the anderson ..............for those chaps who charge this way ...what B&S cable do you have ?


perhaps given my batteries have only only ever been charged over the last few years via the alternator and the optima has been run down quite low on a few occasions they needed a long time on the charger to get them to float

Anyway delighted that at least it all seems to work ...and I can always get the batteries to float stage by connecting the charger to them directly .....although I like the idea of going via the back anderson plug

[cjc_td5]

I have an Anderson plug wired in next to the main battery, taken from the main battery. This is so I can run my air compressor with minimal voltage drop. My SC80 sits right next to it so I can easily confirm the batteries are still linked. By popping the bonnet to access it there is also less chance of me driving away with it still connected!

[drivesafe]

Anyway delighted that at least it all seems to work ...and I can always get the batteries to float stage by connecting the charger to them directly .....although I like the idea of going via the back anderson plug
If you have achieved this once, you can do it at anytime, it will just take a little longer.

Or a shorter time from now on in, if you do it on a regular basis.

[landoman]

If you have achieved this once, you can do it at anytime, it will just take a little longer.

Or a shorter time from now on in, if you do it on a regular basis.


Thanks for all all your help Tim .......and on a final note ....if my batteries are getting to full charge and float is it safe to assume they are ok ......or can they still not hold charge ?
Ill keep an eye on them over the next few days see how the voltage holds

[drivesafe]

This is not a 100% guarantee but as it took so long to get them fully charged, it is a fair indication that they are OK.

[pop058]

Anderson direct to Optima and ctek lead direct to crank. I’ve made a ctek to Anderson adapter lead.

Scott

Not that it is relevant to your (now solved) issue but I made up an adapter for the Anderson plug on the back of my work truck. I cut a square 6mm U-bolt in half, added heatshrink and it allows me to connect anything with alligator clips.

131736 131737

[landoman]

Not that it is relevant to your (now solved) issue but I made up an adapter for the Anderson plug on the back of my work truck. I cut a square 6mm U-bolt in half, added heatshrink and it allows me to connect anything with alligator clips.

131736 131737
That's pretty cool ....but why not just fit an anderson plug in stead of the alligator clips ...

and what gauge of wire did you use to get the power from this modified anderson plug back to your battery ?

[landoman]

This is not a 100% guarantee but as it took so long to get them fully charged, it is a fair indication that they are OK.



Thanks Tim ......I'll watch the voltage and see how I go

[p38arover]

If batteries of different sizes are connected they may equalize at the capacity of the smallest battery, so the larger one may not be fully charged.

Not true.


A further question regarding charging the start battery and optima via the Anderson plug..... I've connected the Ctek charger to the Anderson plug and checked voltages at both the start battery (14.7v) and Optima battery (12.4v). Does this difference in voltage mean that only the optima is being charged? I thought both batteries would be charged at the same time.


They could be connected but still give different readings.


Not the difference quoted unless there is significant voltage drop across the connecting device due to a large current flowing.


What size is the alternator in these vehicles - 80Ah?
If it is then the alternator is (thinks carefully to avoid usual dodgy maths abilities) 16 times more powerful than a 5Ah battery charger. So it is certainly a lot more powerful.

No. Alternators are rated in amperes, not Ah, ditto with chargers. I'd expect the alternator to be up around the 100A range these days.

[pop058]

That's pretty cool ....but why not just fit an anderson plug in stead of the alligator clips ...

and what gauge of wire did you use to get the power from this modified anderson plug back to your battery ?

My small compressor, lead light and battery charger all have clips on them from the OEM. By retaining the clips I can still use them directly on any battery on any vehicle.

[p38arover]

While I would expect it might eventually go into float mode, but because of the voltage drop caused by the 8B&S cable and possibly some bad connections causing more voltage drop, it may never go into float mode.

I must admit I wasn't sure of the size of 8 B&S or 8 AWG so I did a bit of hunting around and found this page: Wire Gauge Comparison Chart (http://www.dave-cushman.net/elect/wiregauge.html)

8 B&S/AWG is only 1/8" or 3.25mm diameter. That's really quite small. I'd prefer to see at least 6 B&S/AWG. Not just for the lower resistance but for the maximum current figure in a jacket (not in air which is about 3 times greater). See AWG Wire Sizes (http://www.ohmslawcalculator.com/awg-wire-chart)

[Tombie]

My small compressor, lead light and battery charger all have clips on them from the OEM. By retaining the clips I can still use them directly on any battery on any vehicle.

I cut all my leads and fitted powerpoles into them.

Then made an Anderson plug to power pole adapter...

I can plug anything anywhere!

[Tombie]

I must admit I wasn't sure of the size of 8 B&S or 8 AWG so I did a bit of hunting around and found this page: Wire Gauge Comparison Chart (http://www.dave-cushman.net/elect/wiregauge.html)

8 B&S/AWG is only 1/8" or 3.25mm diameter. That's really quite small. I'd prefer to see at least 6 B&S/AWG. Not just for the lower resistance but for the maximum current figure in a jacket (not in air which is about 3 times greater). See AWG Wire Sizes (http://www.ohmslawcalculator.com/awg-wire-chart)

My thoughts also - 8B&S is far too small...

[landoman]

Ok that 8AWG may be why I'm having difficulty getting my batteries to go to float from the rear anderson plug .......as the batteries get near the top charge and the voltage ? Drops to to the final top up the wire may not be getting enough of it through to do the job in a reasonable time

I have some 6 AWG ....a change over of the wiring may be the answer ......

also 24 hours after I fully charged my batteries to float stage ( and with the car not been driven ) the voltage is 12.51 on both of them linked via so would that mean that one or both of them is not holding their charge ?

[Tombie]

I’d go 4 AWG if you can!

[Tombie]

You will slowly lose charge, lights, alarm, Traxide unit all draw a little bit off...

Plus any USB ports you have - they all draw even when not having items plugged in.

[landoman]

i
I’d go 4 AWG if you can!


Actually i I checked the wiring and I think it is already 6 AWG ......it is very close in thickness to some 6 AWG I bought recently .......I'd did notice though that the strands of wire in it are a sliver collar ....and not copper like the new 6 AWG I just bought

this original wiring I had gotten from Jaycar as I had told them I wanted to get power to the back and this is what they recommended ........is the sliver stuff less conductive than cooper ?

as for 4 AWG .....will that fit into standard 50 amp andersons ?

[landoman]

You will slowly lose charge, lights, alarm, Traxide unit all draw a little bit off...

Plus any USB ports you have - they all draw even when not having items plugged in.
Thanks .....good to know .....at least I now know I can get my batteries to full charge
.....just need to tune my setup to get it charging in reasonable times

[drivesafe]

also 24 hours after I fully charged my batteries to float stage ( and with the car not been driven ) the voltage is 12.51 on both of them linked via so would that mean that one or both of them is not holding their charge ?
Landoman, I wouldn’t worry to much about that voltage level, as you have only carried out one slow charge cycle.

It will take a number of slow charge cycles to bring your batteries up to their best condition.

if you are not driving your vehicle for a few days, carry out another slow charge cycle and once the charger goes into float, disconnect the charger and remove both negative battery clamps again, and let the batteries sit for a day or two, checking the voltages every so often.

Also, for what you are doing right now, then8B&S ( 7.9mm2 ) is fine for charging, but if you plan to use the rear Anderson plug to charge batteries in a camper trailer or caravan, then upgrade to 6B&S ( 13.5mm2 ).

[bee utey]

........is the sliver stuff less conductive than cooper ?

The silver colour is just electroplated on for better connection and corrosion resistance, the wire inside is still copper.

[landoman]

Landoman, I wouldn’t worry to much about that voltage level, as you have only carried out one slow charge cycle.

It will take a number of slow charge cycles to bring your batteries up to their best condition.

if you are not driving your vehicle for a few days, carry out another slow charge cycle and once the charger goes into float, disconnect the charger and remove both negative battery clamps again, and let the batteries sit for a day or two, checking the voltages every so often.

Also, for what you are doing right now, then8B&S ( 7.9mm2 ) is fine for charging, but if you plan to use the rear Anderson plug to charge batteries in a camper trailer or caravan, then upgrade to 6B&S ( 13.5mm2 ).

Thanks Tim .....great stuff ......this has been a great learning excercise and thanks to all who helped ......wonderful site this Aulro ....

[landoman]

Landoman, I wouldn’t worry to much about that voltage level, as you have only carried out one slow charge cycle.

It will take a number of slow charge cycles to bring your batteries up to their best condition.

if you are not driving your vehicle for a few days, carry out another slow charge cycle and once the charger goes into float, disconnect the charger and remove both negative battery clamps again, and let the batteries sit for a day or two, checking the voltages every so often.

Also, for what you are doing right now, then8B&S ( 7.9mm2 ) is fine for charging, but if you plan to use the rear Anderson plug to charge batteries in a camper trailer or caravan, then upgrade to 6B&S ( 13.5mm2 ).

For the last two days I have been getting my battery to full charge and monitoring it in the morning
typically it has been 12.55 v at 9am
I then plug in my 8 phase charger ( on AGM MODE ) and monitor it throughout the day as it charges with these results
11.00 14.56 v
13.00 14.69 v
14.00. 14.70 v
17.00. 14.73v
19.00. 14.71v
21.00. 14.70

but the charger stays for about 9 hours in the absorption stage ....but as soon as I change modes ( at 21.00 hrs to NORMAL MODE) with in a few minutes it switches to float stage
if I now switch it back to AGM MODE in a few minutes it will also go to float stage.

So why will it not go to float from AGM MODE but will from normal mode and then will also go from AGM mode ....as long as I had gone to Normal mode first ??

Is this because I have one wet cell crank battery and one AGM linked to gether ...( I am feeding the charge into the AGM from Anderson in the rear ) .......and then through the SC80 to the wet cell crank battery .

Is this inability to get both batteries to go to float from the AGM a fault in my charger .....or is it because of the linkage of two batteries and the wet cell normal battery is calling the shots on which mode the charger is getting feedback on to go to float stage .

I guess I now know to use NORMAL MODE ......but as I'm feeding charge initially into an AGM
i thought it logical to set that mode on the charger

your thoughts appreciated .

[drivesafe]

For the last two days I have been getting my battery to full charge and monitoring it in the morning
typically it has been 12.55 v at 9am
I then plug in my 8 phase charger ( on AGM MODE ) and monitor it throughout the day as it charges with these results
11.00 14.56 v
13.00 14.69 v
14.00. 14.70 v
17.00. 14.73v
19.00. 14.71v
21.00. 14.70

but the charger stays for about 9 hours in the absorption stage ....but as soon as I change modes ( at 21.00 hrs to NORMAL MODE) with in a few minutes it switches to float stage
if I now switch it back to AGM MODE in a few minutes it will also go to float stage.

So why will it not go to float from AGM MODE but will from normal mode and then will also go from AGM mode ....as long as I had gone to Normal mode first ??

Is this because I have one wet cell crank battery and one AGM linked to gether ...( I am feeding the charge into the AGM from Anderson in the rear ) .......and then through the SC80 to the wet cell crank battery .

Is this inability to get both batteries to go to float from the AGM a fault in my charger .....or is it because of the linkage of two batteries and the wet cell normal battery is calling the shots on which mode the charger is getting feedback on to go to float stage .

I guess I now know to use NORMAL MODE ......but as I'm feeding charge initially into an AGM
i thought it logical to set that mode on the charger

your thoughts appreciated .
Yellowtops are not normal AGMs and will tolerate a lot of abuse that a normal AGM can’t.

I your charge is happy working in NORMAL mode, as you have posted, just use that at all time.

[drivesafe]

Landoman, this is just a suggestion, next time you try to charge your batteries via the Anderson plug, set your charger to the AGM mode. If the charger does not go into float, try connecting it to either battery and then see if it will go into float.

I suspect the thinner cable may be part of, if not the very reason your charger is not going into float.

Again, I suspect the changing of the charge setting from AGM to NORMAL may be changing the voltage level and current draw at which the charger monitors to determine when it should go into float and while it is AGM, the voltage is right on the boarder line but the voltage drop in the thinner cable is just enough to keep the current draw just too high and stops the charger getting to the level it needs to be able to change to float mode.

By moving the charger directly to the batteries, you remove the voltage drop and this may be enough to cause the charger to go into float while set to AGM.

This is just a suggestion but I base the possible outcome on the fact I have many people doing exactly what you are doing, with many different types of chargers and none are having your problem ( that I am aware of ) and the only difference is that they are all charging via 6B&S ( 13.5mm2 ) instead of your 8B&S ( 7.9mm2 ).

[DiscoJeffster]

Drivesafe, I think you’re spot on. It seems like the charger is just not seeing the voltage get high enough to tell it the batteries have absorbed enough and it’s ready for float. It could be cable thickness or possibly poor connections in the Anderson plugs or battery ends too.

[landoman]

Drivesafe, I think you’re spot on. It seems like the charger is just not seeing the voltage get high enough to tell it the batteries have absorbed enough and it’s ready for float. It could be cable thickness or possibly poor connections in the Anderson plugs or battery ends too.

Ok chaps .....this is a frustrating problem indeeed

put the charger in normal mode on both the wet crank and the optima ....and they go to float pretty much straight away so the batteries are in a good state of charge .

go to the back and plug in and again can get it to go to float in normal mode

Go back a gain to batteries and can get it to float in normal mode .....
try to get it to float on both batteries in AGM mode ...but no go

funny thing is ...IF I CHANGE MODE WITH OUT UNPLUGGING BACK TO NORMAL MODE IT GOES TO FLOAT ...THEN AGAIN CHANGE TO AGM MODE IT NOW GOES TO FLOAT

If I unplug and wait 10 minutes then try to get to float in the AGM mode it just sits on absorption and this is at the batteries ,....same behaviour I get when plugged in at the back ....
....not sure the problem is the wiring from the back because it is 6 AWG think

I am beginning to think the charger I bought is a lemon .....but given I have put anderson plug in one of the leads probably can't return it so will call it the expense of learning

can you reccomend a good charger for this set up ....OEM Battery crank ,optima second battery
to anderson at the back and both batteries linked by SC80

many thanks

[Silenceisgolden]

Ok chaps .....this is a frustrating problem indeeed

put the charger in normal mode on both the wet crank and the optima ....and they go to float pretty much straight away so the batteries are in a good state of charge .

go to the back and plug in and again can get it to go to float in normal mode

Go back a gain to batteries and can get it to float in normal mode .....
try to get it to float on both batteries in AGM mode ...but no go

funny thing is ...IF I CHANGE MODE WITH OUT UNPLUGGING BACK TO NORMAL MODE IT GOES TO FLOAT ...THEN AGAIN CHANGE TO AGM MODE IT NOW GOES TO FLOAT

If I unplug and wait 10 minutes then try to get to float in the AGM mode it just sits on absorption and this is at the batteries ,....same behaviour I get when plugged in at the back ....
....not sure the problem is the wiring from the back because it is 6 AWG think

I am beginning to think the charger I bought is a lemon .....but given I have put anderson plug in one of the leads probably can't return it so will call it the expense of learning

can you reccomend a good charger for this set up ....OEM Battery crank ,optima second battery
to anderson at the back and both batteries linked by SC80

many thanks

It won't be the wire thickness. Thinner gauge means LESS current from charger, so if anything it will drop into float more easily. (It goes to float when current drops enough). Almost certainly the extra current drawn by the Traxide is stopping it float in AGM mode. Make the effort, remove the Traxide earth, temporarily bridge the batteries and I betcha it goes into float. Long term, get a charger rated at a higher current - it will drop into float at a higher current level than your 5 amp job.

[Tombie]

It’s not frustrating. Don’t let it be..
It’s a cheap charger and thin cables...

Be happy they’re charged and move on, life’s too short to worry!

[landoman]

It’s not frustrating. Don’t let it be..
It’s a cheap charger and thin cables...

Be happy they’re charged and move on, life’s too short to worry!

Guess I just like things tidy and to work reliably

If it doesn't go to float and it stays too long in absorption can you damage the battery ?

[Tombie]

Run it it Wet and it drops in ok... so no it won’t do damage..

[LRD414]

As per my earlier post, my Ctek MXS 5A charger works perfectly for your exact setup. Note that my cable to the rear Anderson came with the D4-5S Traxide kit so it may be a larger gauge than yours and if so this would be the only difference to you. I don’t disconnect the Traxide and it doesn’t cause any issues for the charger getting to float.

Scott

[scarry]

Guess I just like things tidy and to work reliably

If it doesn't go to float and it stays too long in absorption can you damage the battery ?

But you bought a cheap charger?

A 5A Ctek,as an example, is not an immensely expensive piece of kit.

Quality brand and should work perfectly.

Then you will have nothing to worry about.

A low cost charger could also damage the batteries,meaning the money you saved on a cheap charger,may cost more in the long run.

Just my 2 cents worth

[landoman]

As per my earlier post, my Ctek MXS 5A charger works perfectly for your exact setup. Note that my cable to the rear Anderson came with the D4-5S Traxide kit so it may be a larger gauge than yours and if so this would be the only difference to you. I don’t disconnect the Traxide and it doesn’t cause any issues for the charger getting to float.

Scott

Thanks I think I'll get a ctek charger . I would just like the thing to work every time and predictably and this charger I have is just not doing that . Do you run your ctek 5 amp on the normal setting or the AGM setting ....given your anderson plug is going back to your optima like mine ?
I am using a fairly thick wire I think it's 6 AWG but I do have a short section of thinner wire close to the battery that has an inline 30 amp fuse . Not sure if this would make a difference .

[LRD414]

I just leave it on AGM whether it’s going to the Optima or the cranking battery (I can connect either way).

Scott

[Tombie]

Personally I’d go this - bloody excellent bit of kit...

VICTRON BLUE SMART IP65 12V PRO BATTERY CHARGER, BLUETOOTH 7A,10A, 4WD, MARINE | eBay (https://rover.ebay.com/rover/0/0/0'mpre=https%3A%2F%2Fwww.ebay.com.au%2Fulk%2Fitm%2 F391881889157)

[drivesafe]

Hi Landoman, I looked up the specs for your battery charger and it actually states that it can take up to 55 hours before the charger automatically goes into float mode, but it also states that the maximum total battery capacity it is designed to charge is 120Ah.


While you have around 145Ah of total battery capacity, and you are only just above what the charger should be able to handle, so it should be fine but will take longer to complete a full charge cycle.


The fact the charger goes into float when in the NORMAL setting but not while in the AGM setting may simply be caused by the slightly large battery capacity than it is designed for.


In any case, because it works properly in the NORMAL setting, I personally would just just keep the charger you have and leave it set in the NORMAL setting at all times.


The only difference between the NORMAL and the AGM setting is the voltage used in the final stage of the ABSORPTION mode. This is 14.4v vs 14.7v and is pretty well irrelevant because both voltage levels will get both batteries fully charged.


The only suggest I would make is to carry out charging your batteries with the battery charger a little more often.