PRojecta Battery Charger Negative Lead Placement [Archive]

Kidbeen

10th February 2018, 08:28 PM

DiscoMick

10th February 2018, 08:43 PM

You could trace the battery negative lead back to the chassis and just piggyback on the same bolt.
Why not put a timer on the battery charger and set it to turn on for a few hours every week?

p38arover

10th February 2018, 09:08 PM

I am/was an electronics technician and I'd connect the black lead directly to the negative of the battery.

Kidbeen

10th February 2018, 09:31 PM

I am/was an electronics technician and I'd connect the black lead directly to the negative of the battery.

Someone else also told me that and said "because it's a defender". HAha.

Projecta say for a battery not attached to the vehicle to place it on the post. What is their reasoning to do it differently when in the vehicle? An explosion or shorting out electronics?

bee utey

10th February 2018, 09:36 PM

Connecting a negative clamp away from the battery was seen as good practice to avoid sparking near a gassing battery. Most modern batteries are pretty well sealed so the risk is lower. If you're in doubt, make a charging adaptor lead with a fuse and an Anderson plug outside of the battery box that you can just plug the charger into. Many chargers come with a lead that has an inline plug and spare connector in the kit for this purpose.

Disco Mick's suggestion for a timer is what I'd do too, electronic timers are pretty cheap.

DiscoMick

10th February 2018, 09:36 PM

Gas discharges from the battery?
Defender's don't have enough electronics to be an issue. Discoverys do and have a separate negative post.

p38arover

10th February 2018, 09:54 PM

Connecting a negative clamp away from the battery was seen as good practice to avoid sparking near a gassing battery.

Yes. But as I don't connect/disconnect the leads with the charger switched on....

Using a 50A Anderson plug is a good idea. It can be mounted away from the battery box in an easy to access location. I can charge my aux. batteries via the rear mounted Anderson plug (I have a self-resetting circuit breaker in series with that plug).

Kidbeen

10th February 2018, 10:11 PM

Also when the motor is running, I have a Redarc switching mechanism so that when the Starter Battery is fully charged it switches to the auxillary battery to charge it. I assume that with the Projecta charger connected to the starter battery it does not then switch automatically to the auxilliary. Could someone clarify that for me. Is it only a switching mechanism via the alternator charge?

bee utey

10th February 2018, 10:49 PM

Yes. But as I don't connect/disconnect the leads with the charger switched on....

Of course, because you have the knowledge. Many people don't. [smilebigeye]

bee utey

10th February 2018, 10:52 PM

Also when the motor is running, I have a Redarc switching mechanism so that when the Starter Battery is fully charged it switches to the auxiliary battery to charge it. I assume that with the Projecta charger connected to the starter battery it does not then switch automatically to the auxiliary. Could someone clarify that for me. Is it only a switching mechanism via the alternator charge?

Redarc sell dual battery isolators that sense the main battery voltage and connect it to the auxiliary battery when it reaches a certain voltage. Unless your unit is different to normal it will link the batteries just fine in your situation. You should see a red light on the unit when the batteries are linked.

Old Farang

10th February 2018, 11:46 PM

A situation like you have is the ideal place to use a Ctek or similar smart charger. It will do all that you want without timers, battery clips or concerns about where to connect it. Ctek comes with a small insulated plug designed to be left connected to the battery, just unplug it when you want to use the car.

Kidbeen

11th February 2018, 08:28 AM

Redarc sell dual battery isolators that sense the main battery voltage and connect it to the auxiliary battery when it reaches a certain voltage. Unless your unit is different to normal it will link the batteries just fine in your situation. You should see a red light on the unit when the batteries are linked.

Thanks. It's a Redarc 'Smart Start SBI Dual Battery Isolator Solenoid'. Unfortunately, there are no specific instructions re charging with a battery charger.

AK83

11th February 2018, 01:27 PM

Thanks. It's a Redarc 'Smart Start SBI Dual Battery Isolator Solenoid'. Unfortunately, there are no specific instructions re charging with a battery charger.

Like bee utey said: when you connect the charger to the starter battery, the battery is getting over 12.7volts via the charger, so the Redarc will sense this and it will connect them both, so you will charge both batteries at the same time.
Not a bad thing either!

A while back I was having trouble with my alternator in my Tdi, and to keep me going whilst I received the new alternator, I'd connect the charger(probably the same Projecta that you have) to the starter battery, and it's charge both batteries easily overnight(actually in a few hours).
Had to do this for about a week, using the D1 as a daily driver.

No problems.

As there is no easy to get too earthing post in the D1, I just connected it to the battery negative terminal .. same thing really.

Also note that the Projecta charger doesn't start charging on immediate connection to the battery, and is off when not connected but still plugged in to the mains power.

So there is a delay in when it actually starts charging the battery(s). No problems with sparking/gassing/explosions! :D
It charges when the unit starts up it's internal fan.

Does your Projecta charger have the options to select battery type as well?
You can set it to work as a power supply(13.8v from memory) or Gel, AGM, Wet or Calcium types are the options.

Kidbeen

11th February 2018, 02:16 PM

AK83 - Thanks for that. Yes it has the options to set battery type. The starter is a normal wet cell but the auxilliary one is a lead crystal so it is probably an AGM. The Redarc will switch the charging to the Lead Crystal battery but probably won't do the maintenance on it that way; desulphication etc. I have the charger connected now for the first time. There is a solid red light showing on the Redarc thingo.

I am still working my way around this Defender which I have had for about 14 months. From the photo attached you can see it has a plug fitted for a charger but my Projecta only has the alligator clamps fitted.

What are the small boxes shown on the wall of the battery compartment? Are they just standard fittings or are they there because my vehicle is fitted out as a motor home.

trout1105

11th February 2018, 02:27 PM

What are the small boxes shown on the wall of the battery compartment? Are they just standard fittings or are they there because my vehicle is fitted out as a motor home.

Those are relays [thumbsupbig]

Kidbeen

11th February 2018, 02:41 PM

In a nutshell what is a relay?

Old Farang

11th February 2018, 02:41 PM

From the photo attached you can see it has a plug fitted for a charger but my Projecta only has the alligator clamps fitted.
That plug is from a Ctek charger.

trout1105

11th February 2018, 02:49 PM

In a nutshell what is a relay?

It is basically a switch that allows you to use a low current to turn on high current applications, eg spotlights.

p38arover

11th February 2018, 04:23 PM

That black and orange connector in the photo is a CTek unit. A CTek charger will plug straight into that.

Can you return the Projecta for an exchange to Ctek?

Kidbeen

11th February 2018, 04:38 PM

Unfortunately, I have had the Projecta for sometime now. It a pity I did not know about that when I bought the Projecta because at the same time I was considering a Ctek.

Kidbeen

11th February 2018, 04:46 PM

Maybe I will get a Ctek down the track. What model would you recommend?

DiscoMick

11th February 2018, 05:16 PM

The Projecta should be fine. Mine has been great. The alligator clips will work fine. As the battery nears maximum charge the charger will lower the current. Once the battery is fully charged the Projecta will switch off. Periodically it will test the battery. If it has dropped it will charge it and then switch off again. You can leave it connected long-term without a problem. Our camper trailer is left connected for weeks at a time. This process is a good way to keep batteries healthy.

Kidbeen

11th February 2018, 07:10 PM

Redarc sell dual battery isolators that sense the main battery voltage and connect it to the auxiliary battery when it reaches a certain voltage. Unless your unit is different to normal it will link the batteries just fine in your situation. You should see a red light on the unit when the batteries are linked.

I had to disconnect my charger before it was charged as it was getting dark and I had the windows down and did not want those bluddy Asian geckos getting in the cabin as we have plenty of them. Sometime after, the red light on the Redarc was still glowing. Is that normal and when will it go out?

bee utey

11th February 2018, 07:35 PM

I had to disconnect my charger before it was charged as it was getting dark and I had the windows down and did not want those bluddy Asian geckos getting in the cabin as we have plenty of them. Sometime after the red light on the Redarc was still glowing. Is that normal and when will it go out?

The light will go out when the battery voltage goes down to around 12.7 volts. The isolator draws enough current that this will happen within a couple of hours at most. Flashing the high beams on usually drops the voltage below this point quite quickly if you want it to go out sooner.

DiscoMick

11th February 2018, 07:42 PM

If the red light shows the batteries are connected it means the starting battery is in good shape, probably at least 80% depending on where the cutoff point is set. So if the red light is on that's a good sign.
Bear in mind that about 12.8 is fully charged and 12.0 is about 50%.

Kidbeen

11th February 2018, 08:11 PM

The light will go down when the battery voltage goes down to around 12.7 volts. The isolator draws enough current that this will happen within a couple of hours at most. Flashing the high beams on usually drops the voltage below this point quite quickly if you want it to go out sooner.

Of course when you get back from a trip you don't think to look at the battery under the passenger's seat etc,. That's why I have never seen the red LED glowing on the Redarc.

AK83

12th February 2018, 09:58 AM

The light will go out when the battery voltage goes down to around 12.7 volts. The isolator draws enough current that this will happen within a couple of hours at most. Flashing the high beams on usually drops the voltage below this point quite quickly if you want it to go out sooner.

Can stay on all night and into the morning when you start 'er up again.
I had to replace my new start battery a week or so ago due to a dead cell in the 'new' one(1 yr old).
On at least 3 occasions now, starter voltage has been at or above 12.7 after about 8 or so hrs of sitting overnight!

So just a heads up as to other possibilities, depending on the condition of the main battery.

Of course when you get back from a trip you don't think to look at the battery under the passenger's seat etc,. That's why I have never seen the red LED glowing on the Redarc.

You can easily setup an LED somewhere easily seen via the free blue wire with the insulated spade hanging off the isolator.
Just wire up this blue wire to the positive lead of the LED, and the negative lead wired to an earth. This lights up as the red indicator light on the SBI isolator.
You can get a cheap($2-ish) LED from Jaycar(or other such places) in a chrome bezel that is perfect for the job. Make sure that it's a 12v LED tho, otherwise you need a resistor.

Other tip is that you can add a switch on this same wire to enable the isolator as a jump start system if the main battery ever fails .. which is what happened to me a couple of months back.(that new battery with a dead cell!)
That same blue wire will hook up to a simple switch(two post switch is fine).
Nice easy jumperlead-less jump start if ever required.
Wiring up isn't too complicated either.

DiscoMick

12th February 2018, 10:15 AM

You could also buy a battery meter such as the ones made by Narva or others from Autobarn or the other similar shops, connect it to the battery and run the leads out the hole in the front of the battery box to somewhere where it can be seen, such as on the dash or console. Then you will always know the state of the battery.
I have one connected to my second battery, which is hidden down the back under the rear of the drawers and the seat, making it hard to reach, but I can see its state at a glance by looking at the meter, which is on the side below the window. If my second battery has plenty of charge I know it means my starting battery is also in good shape and the Traxide dual battery controller has the two batteries linked.
My rooftop 80 watt solar panel charges the starting battery, so in theory I should never have a flat starting battery, so the two batteries should always be linked. That's assuming I park in the sun and drive it regularly, of course.
BTW I have used my Projecta 240 volt charger on the second battery and on the camper battery plenty of times with the negative attached to the negative battery post and it has never caused a problem. It might only be an issue if your battery was sick and venting lots of fumes.
Defenders don't have many electronics, unlike Disco 3s and 4s, which have a special post in the engine bay to which the negative has to be attached to avoid disturbing their electronics.

Kidbeen

12th February 2018, 10:41 PM

What about one of these to check battery charge? Anyone got one?

trout1105

12th February 2018, 11:00 PM

What about one of these to check battery charge? Anyone got one?

I bought half a dozen of these things via eBay for about $7 each, The ones I got even have a temp readout as well as voltage on them.
I plug them into my ARK power boxes cig lighter outlets so that I can see "Exactly" what voltage I have on every battery, Good little units [thumbsupbig]

Ranga

13th February 2018, 08:08 AM

What about using a small solar panel?

p38arover

13th February 2018, 09:08 AM

What about one of these to check battery charge? Anyone got one?

I have something similar that has two USB charge points. It cycles the display between volts and current (for devices plugged into it).

DiscoMick

13th February 2018, 10:31 AM

What about one of these to check battery charge? Anyone got one?
I have a Jaycar one. It is quite useful if you don't want to fit a permanent meter.

DiscoMick

13th February 2018, 10:33 AM

What about using a small solar panel?
A small solar panel is a good idea to keep a trickle charge going in and keep the battery healthy. Batteries like to receive a slow charge for a while and then have a rest, at night with solar, so it works well. You could just sit it on the dash and plug it into the cigarette lighter.

trout1105

13th February 2018, 10:44 AM

A small solar panel is a good idea to keep a trickle charge going in and keep the battery healthy. Batteries like to receive a slow charge for a while and then have a rest, at night with solar, so it works well. You could just sit it on the dash and plug it into the cigarette lighter.

You have to have the ignition on to use the cigarette lighter outlet.

p38arover

13th February 2018, 11:20 AM

What about using a small solar panel?

How small? The one I have gives virtually useless output. I bought it for my motorbike.

DiscoMick

13th February 2018, 12:12 PM

You have to have the ignition on to use the cigarette lighter outlet.

True. I should have explained that. I have an extra cigarette plug connected directly to one of my batteries.

I have an old 15amp panel I use for reviving sick batteries.

trout1105

13th February 2018, 12:14 PM

True. I should have explained that. I have an extra cigarette plug connected directly to one of my batteries.

I have an old 15amp panel I use for reviving sick batteries.

What a good idea [thumbsupbig]

drivesafe

13th February 2018, 12:44 PM

True. I should have explained that. I have an extra cigarette plug connected directly to one of my batteries.

I have an old 15amp panel I use for reviving sick batteries.
Hi Mick, is that amps or watts?

andrew53

15th February 2018, 11:25 AM

Attaching a screen shot of the instructions for the Projecta model I have. I only drive my Defender once a month and thought I should charge both my starting and auxillary batteries.

The instructions state for a battery within the vehicle to attach the negative lead to the chassis rather than the negative post on the battery. Does that mean I have to clean a patch on the chassis underneath the vehicle so I get a good earth. Where do you place the negative lead from the charger?

Also, if I only use my vehicle monthly how often should I charge the batteries to maximise my battery performance with the 7 stage charging process.

Once charged you leave it on and being a 7 stage charger it will just top up when is senses a drop in the battery as it has a built in trickle charge and I have the same charger. I personally don't think you need to go to a body earth, I don't on mine and it works fine.

DiscoMick

15th February 2018, 04:45 PM

Hi Mick, is that amps or watts?Watts. Sorry. Electrickery confuses me.

Kidbeen

18th February 2018, 01:32 PM

What about one of these to check battery charge? Anyone got one?

I popped into Jaycar during the week and purchased one of those cigarette lighter battery meters. Put it in my Holden Rodeo and when turning the ignition I was getting a voltage of 12.6/ 12.7 and when the car was running 13.9 to 14.2.

So then I transferred it to the Defender and as previous posts tells you I have just finishing charging both batteries with my Projecta. On the starter battery the Redarc solenoid LED light glowed for five days after. When I turned the ignition on the defender it showed a reading of 11.5. Is there an explanation of why it could be reading so low at the cigarette lighter when the battery is fully charged? When running it showed 13.8 to 14.

trout1105

18th February 2018, 01:45 PM

I popped into Jaycar during the week and purchased one of those cigarette lighter battery meter. Put it in my Holden Rodeo and when turning the ignition I was getting a voltage of 12.6/ 12.7 and when the car was running 13.9 to 14.2.

so than I transferred it to the Defender and as previous posts tell you I have just finishing charging both batteries with my Projecta. On the starter battery the Redarc solenoid LED light glowed for five days after. When I turned the ignition on the defender it showed a reading of 11.5. Is there an explanation of why it could be reading so low at the cigarette lighter when the battery is fully charged? When running it showed 13.8 to 14.

The readings on the Rodeo look to be "Spot On" Not so much on the Defender.
I put one of these units on my Wife's Hilux and got a reading of 10.5v so I checked the acid levels in then battery and I could see the plates in a couple of the cells it was that low, I topped the battery up with distilled water and the voltage came up to 11.8v after a 100k run at highway speeds (13.8v-14v when running) So it looks like I am up for a new battery for her truck.
My D2a reads 12.7v before start up and 14v when running initially which drops to 13.5 after a while So I think I am safe for a while there.

bee utey

18th February 2018, 01:46 PM

I popped into Jaycar during the week and purchased one of those cigarette lighter battery meter. Put it in my Holden Rodeo and when turning the ignition I was getting a voltage of 12.6/ 12.7 and when the car was running 13.9 to 14.2.

so than I transferred it to the Defender and as previous posts tell you I have just finishing charging both batteries with my Projecta. On the starter battery the Redarc solenoid LED light glowed for five days after. When I turned the ignition on the defender it showed a reading of 11.5. Is there an explanation of why it could be reading so low at the cigarette lighter when the battery is fully charged? When running it showed 13.8 to 14.

It just shows that there is another load on the cigarette lighter circuit. Battery voltage should be measured at the battery, so a "fix" is to wire a separate socket and fuse directly from the battery to the dash. There's always a use for an extra socket anyway.

DiscoMick

18th February 2018, 01:49 PM

Kidbeen

18th February 2018, 03:37 PM

It just shows that there is another load on the cigarette lighter circuit. Battery voltage should be measured at the battery, so a "fix" is to wire a separate socket and fuse directly from the battery to the dash. There's always a use for an extra socket anyway.

That's what I was thinking, that there is a diversion of power to somewhere else.

As I said previously, when I charged this battery the solenoid glowed for 5 days after so it was definitely fully charged. See the attached which I pulled up from a Redarc forum.

But I will also have look at the battery cells again as others have suggested.

Kidbeen

20th February 2018, 06:42 PM

It just shows that there is another load on the cigarette lighter circuit. Battery voltage should be measured at the battery, so a "fix" is to wire a separate socket and fuse directly from the battery to the dash. There's always a use for an extra socket anyway.

Today I had access to a multimeter. The starter battery measured 12.51v and the auxilliary also measured 12.51v and because I had been on a 300k trip over the weekend the LED on the Redarc thingo was still glowing. Then I turned the ignition on and the cigarette lighter battery meter measured the starter battery at 11.7v. So somewhere between the battery and the cigarette lighter there is a 0.81v diversion of current. All very interesting.

p38arover

20th February 2018, 09:24 PM

So somewhere between the battery and the cigarette lighter there is a 0.81v diversion of current. All very interesting.

No, there is a 0.81 voltage drop. That will be caused by either high resistance in that circuit from the fuse box and/or something is drawing current.

The meter will be high impedance so it will not load the cigarette lighter feed. However, there maybe other items that draw current.

You need to check the voltage at the fuse for that circuit. The voltage drop could be between the battery and the fuse.

It's all to do with Ohm's Law.