Battery charge voltage info poll.

[drivesafe]

If any of you have the time, and has access to a digital multi meter, would you like to take part in a simple battery voltage test.

The idea of the poll is to see whether cranking batteries are not being charged above the 70% level that is proposed in quite a few articles or is it more like 90+% the state at which I find most vehicle’s cranking batteries to be at.

There are 10 basic questions and just answering the first will do, but if you have the time and info available, answers to any or all of the other nine would be very helpful in see just how alternator battery charging works in different vehicles.

The info can be from any vehicle, not just your Landy.

The first question will be more accurate the longer the vehicle's motor has been off, preferably 12 or more hours after the motor was last on.

1 ) What is the voltage at the cranking battery’s terminals.

2 ) Type of vehicle.

3 ) What make and type of battery ( a model number will do )

4 ) When was the last time the vehicle was driven.

5 ) How long was the last drive

6 ) Is this your day to day drive or a once a week vehicle

7 ) Alternator size

8 ) Is this your tow vehicle or other.

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start )

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive.

The last two questions are for gaining a better idea of how different alternator operations. Alternator operation in most vehicles is now controlled by the vehicle’s Engine Management Computer. This independent control not only means that there will be differences in alternator operations between vehicle makes but even between same make and models.

I Had an 03, Mark III Range Rover, first version of the current model. It’s alternator went to 14.3v soon after the motor started and stayed there for as long as the motor was running.

I now have an 08 Mark III Range Rover, the latest version of the current model. The alternator in the 08 RR does not start generating power for about 30 to 50 seconds after the motor is first started and the initial voltage can then be anything from 14.2 to 14.9 volts and does not seem to be influenced by ambient temperatures.

Exactly 30 minutes after the first start, the voltage lowers and can be as low as 13.2v.

For anyone trying to get any form of alternator operations info, it is almost impossible to get any data form any of the manufacturers, so your input can be very helpful.

A suggestion to make the data entering easier to post, copy the ten questions and paste them in a word processor, add your data under each question and then copy and paste into a reply.

[Redback]

I can do this, I can even give the data from the Madmans EMS1 battery monitor as well if you want.

Baz.

[weeds]

happy to help out.....although i do have two aux batteries and solar panel, anything i need to do to get the info for you

[drivesafe]

Hi and thanks Baz and Kelvin, just post the info up and we can all see whether batteries are fully charged by an alternator or whether there is a problem, as many notable ( B/S ) articles state.

Excuse my scepticism but after 20 years of check vehicle batteries I am yet to come across more than about 2% of vehicles that have batteries that are anything below 90% charged and even then there is usually a reason.

The problem is that there now so many people trying to make money out of convincing people that their batteries are not charging and that they need to spend big bucks to get their batteries fully charged.

Anyway, this test should give some idea of what is happening in the real world.

Cheers.

[Psimpson7]

Here you go Tim,

1 ) What is the voltage at the cranking battery’s terminals. 12.65v (Car had been off for at least 24hrs)

2 ) Type of vehicle. TD5 Defender.

3 ) What make and type of battery ( a model number will do ) 2xCentury N70ZZ4wd. No smart system, just hard wired together. Ones 2 months old, the other about 13 months

4 ) When was the last time the vehicle was driven. Couple of days ago

5 ) How long was the last drive. 50km

6 ) Is this your day to day drive or a once a week vehicle.. Doesn’t get used that much but then does a yearly trip which can add a few!

7 ) Alternator size 120a

8 ) Is this your tow vehicle or other. My everything vehicle.

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 14.45 (taken as soon as I could get the probes to the battery after starting. - probably about 10 seconds)

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.15 (was 40 minutes)

[Graeme]

Q9. Exactly when do you want the measurement? - eg during starter motor operation, within 3 seconds of starting, 10 seconds after starting, etc.

[Blknight.aus]

Here you go Tim,

1 ) What is the voltage at the cranking battery’s terminals. 12.65v

2 ) Type of vehicle. TD5 Defender.

3 ) What make and type of battery ( a model number will do ) 2xCentury N70ZZ I think. No smart system, just hard wired together. Ones 2 months old, the other about 13 months

4 ) When was the last time the vehicle was driven. Couple of days ago

5 ) How long was the last drive. 50km

6 ) Is this your day to day drive or a once a week vehicle.. Doesn’t get used that much but then does a yearly trip which can add a few!

7 ) Alternator size 120a

8 ) Is this your tow vehicle or other. My everything vehicle.

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 14.45

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.15 (was 40 minutes)


as per that for big red +/- a bit which may be multi meter variance. but big red is a daily driver, Main battery is about a year old (replaced just after the 100K km service

do you want old school fozzy or just the stuff for big red.

[weeds]

Here you go Tim,

1 ) What is the voltage at the cranking battery’s terminals. 12.71v

2 ) Type of vehicle. 300tdi Defender.

3 ) What make and type of battery ( a model number will do ) 1 x RACQ 4704, 1 x AMPTECH D87L, 1 x Exide ED6. No smart system, marine isolator thats never used. Age have no idea between 12-24 months

4 ) When was the last time the vehicle was driven. 1hr 30min

5 ) How long was the last drive. 8km

6 ) Is this your day to day drive or a once a week vehicle.. everyday

7 ) Alternator size 100a

8 ) Is this your tow vehicle or other. My everything vehicle.

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 13.76

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. forgot i needed to go for a drive, will do again in the morning

[drivesafe]

Q9. Exactly when do you want the measurement? - eg during starter motor operation, within 3 seconds of starting, 10 seconds after starting, etc.

Hi Graeme, if you take the reading about 60 seconds after starting your motor, this will guaranty the alternator is up and running at the required operating voltage.

Cheers.

[justinc]

And here is mine Tim,

1 ) What is the voltage at the cranking battery’s terminals. 12.56V

2 ) Type of vehicle. RRC 4BD1T

3 ) What make and type of battery ( a model number will do ) Delkor 22FR520

4 ) When was the last time the vehicle was driven. This evening

5 ) How long was the last drive 12 minutes (Used to be 5 mins...:angel:)

6 ) Is this your day to day drive or a once a week vehicle Daily driver

7 ) Alternator size 120A

8 ) Is this your tow vehicle or other. Tow, touring, everything

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) within 15 seconds, 13.9V, and climbing slowly
10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. After 12 minutes, it is still charging at 14.2V
Incidentally, with the SC80 I get 14.2V AT the Anderson plug, too! :)
JC, (ps did you get my PM Tim? thanks for the help!:))

[awabbit6]

Tim, are you concerned about the effect of having an auxiliary battery connected? I can give you the readings with or without.
What would you prefer?

[drivesafe]

Tim, are you concerned about the effect of having an auxiliary battery connected? I can give you the readings with or without.
What would you prefer?

No, but both readings would be very interesting, Thanks.

Cheers.

[drivesafe]

(ps did you get my PM Tim? thanks for the help!:))

Yes thanks Justin and glad to see everything seems to be sorted now.

Cheers.

[Disco_owner]

I'll be happy to participate ,I will take some measurements of both cranking batteries ie Disco and Rangie and post up the results in morning.

[LOVEMYRANGIE]

If any of you have the time, and has access to a digital multi meter, would you like to take part in a simple battery voltage test.

The idea of the poll is to see whether cranking batteries are not being charged above the 70% level that is proposed in quite a few articles or is it more like 90+% the state at which I find most vehicle’s cranking batteries to be at.

There are 10 basic questions and just answering the first will do, but if you have the time and info available, answers to any or all of the other nine would be very helpful in see just how alternator battery charging works in different vehicles.

The info can be from any vehicle, not just your Landy.

The first question will be more accurate the longer the vehicle's motor has been off, preferably 12 or more hours after the motor was last on.

1 ) What is the voltage at the cranking battery’s terminals. 12.8V (2x)

2 ) Type of vehicle. '93 RRC

3 ) What make and type of battery ( a model number will do ) 2 x Supercharge Allrounder 1 x MRV70, 1 x MRV70L dual connected

4 ) When was the last time the vehicle was driven. today

5 ) How long was the last drive 45mins

6 ) Is this your day to day drive or a once a week vehicle Daily

7 ) Alternator size Iskra 120A (actually for a Massey Ferguson!)

8 ) Is this your tow vehicle or other. Tow.

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 12.2v @ crank, 13.8v @ idle, 14.5ish @ +1100rpm

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.2v.

The last two questions are for gaining a better idea of how different alternator operations. Alternator operation in most vehicles is now controlled by the vehicle’s Engine Management Computer. This independent control not only means that there will be differences in alternator operations between vehicle makes but even between same make and models.

I Had an 03, Mark III Range Rover, first version of the current model. It’s alternator went to 14.3v soon after the motor started and stayed there for as long as the motor was running.

I now have an 08 Mark III Range Rover, the latest version of the current model. The alternator in the 08 RR does not start generating power for about 30 to 50 seconds after the motor is first started and the initial voltage can then be anything from 14.2 to 14.9 volts and does not seem to be influenced by ambient temperatures.

Exactly 30 minutes after the first start, the voltage lowers and can be as low as 13.2v.

For anyone trying to get any form of alternator operations info, it is almost impossible to get any data form any of the manufacturers, so your input can be very helpful.

A suggestion to make the data entering easier to post, copy the ten questions and paste them in a word processor, add your data under each question and then copy and paste into a reply.

Both of mine each have a +ve lead direct to starter motor, a smaller lead cross connecting the two +ve terminals together and an earth lead from batt>chassis>body>engine.
I run A/C, EAS compressor, 2 lightforce, 2 IPF 900's with 130w bulbs, 2 x Hella driving lights, 2 130w high beams, massive Alpine amp & a CB all at the same time at road speed and I still can't get my volt gauge which runs off the ignition acc wire to drop below 13v!! At idle, with all this and in "D" it only drops to about 11.8v on the gauge but still reads at least 13.2v at the batteries!!

Cheers

Andrew

[amtravic1]

1 ) What is the voltage at the cranking battery’s terminals. 12.6

2 ) Type of vehicle. Rangie Classic, 3.9 Disco motor

3 ) What make and type of battery ( a model number will do ) Dekka Intimidator

4 ) When was the last time the vehicle was driven. 12 hours ago

5 ) How long was the last drive 85 kms

6 ) Is this your day to day drive or a once a week vehicle. Daily

7 ) Alternator size 100 amp

8 ) Is this your tow vehicle or other. other

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 14.6 volts

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive.
14.2 volts


Ian

[Redback]

1 ) What is the voltage at the cranking battery’s terminals. 12.21 11.5

2 ) Type of vehicle. DISCO TD5

3 ) What make and type of battery ( a model number will do ) EXIDE ENDURANCE 950CCA

4 ) When was the last time the vehicle was driven. 12Hr ago

5 ) How long was the last drive 45 MIN

6 ) Is this your day to day drive or a once a week vehicle BOTH

7 ) Alternator size 120A

8 ) Is this your tow vehicle or other. YES

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 14.5 14.6

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.2 13.9 to 14.2


The Madman numbers are in green

[weeds]

12 hours on form the last test

1 ) What is the voltage at the cranking battery’s terminals. 12.55v

2 ) Type of vehicle. 300tdi Defender.

3 ) What make and type of battery ( a model number will do ) 1 x RACQ 4704, 1 x AMPTECH D87L, 1 x Exide ED6. No smart system, marine isolator thats never used. Age have no idea between 12-24 months

4 ) When was the last time the vehicle was driven. 12hr prior

5 ) How long was the last drive. 8km

6 ) Is this your day to day drive or a once a week vehicle.. everyday

7 ) Alternator size 100a

8 ) Is this your tow vehicle or other. My everything vehicle.

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 13.8v after 10 sec but still climbing slowly

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 13.83v 23km drive 35min running time

[seano87]

1 ) What is the voltage at the cranking battery’s terminals. 12.9

2 ) Type of vehicle. 300tdi Discovery

3 ) What make and type of battery ( a model number will do ) Supercharge NS70 - Age - 07/2005, so a little over 4 years :o

4 ) When was the last time the vehicle was driven. 12 hours ago

5 ) How long was the last drive 15 kms

6 ) Is this your day to day drive or a once a week vehicle. Daily

7 ) Alternator size 80 amp

8 ) Is this your tow vehicle or other. both - tow and general daily use

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 14.4 volts

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive.
14.3

Seano

[Disco_owner]

NOTE , There are 2 Vehicles;;

----------------------------------------------------------------------
1 ) What is the voltage at the cranking battery’s terminals.
12.68 volts

2 ) Type of vehicle. Range Rover Classic , 3.9 V8

3 ) What make and type of battery ( a model number will do )
AC Delco , UN2974 , S80D26R

4 ) When was the last time the vehicle was driven. This morning

5 ) How long was the last drive 30-40minutes

6 ) Is this your day to day drive or a once a week vehicle
Once a Week Drive
7 ) Alternator size Denso A1271 , 100A

8 ) Is this your tow vehicle or other. No Towing

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 13.6 volts
10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 13.6 volts

----------------------------------------------------------------------

1 ) What is the voltage at the cranking battery’s terminals.

12.10 volts

2 ) Type of vehicle. Tdi Discovery 1997

3 ) What make and type of battery ( a model number will do )

Champion Extra HD N50ZZ

4 ) When was the last time the vehicle was driven. A while Ago , not sure

5 ) How long was the last drive Hasn't been driven for a while

6 ) Is this your day to day drive or a once a week vehicle
once a month Drive:D
7 ) Alternator size Magneti Marelli , 80A , I think

8 ) Is this your tow vehicle or other. My Tourer

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 13.9 Volts

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive.

Unfortunately can't answer this as vehicle hasn't been driven for a while

----------------------------------------------------------------------

[p38arover]

1 ) What is the voltage at the cranking battery’s terminals. 11.89 before start (with SC40 connected).

2 ) Type of vehicle. 1995 Range Rover 4.6 HSE

3 ) What make and type of battery ( a model number will do ) SuperCharge MF95D31R - about 2 months old.

4 ) When was the last time the vehicle was driven. 4-5 days ago

5 ) How long was the last drive 20km

6 ) Is this your day to day drive or a once a week vehicle everyday to work

7 ) Alternator size 120A

8 ) Is this your tow vehicle or other. Everything

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 13.89 with SC40 connected

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. Will need to check after I drive to work tomorrow (about 20 min drive). After 5 mins running today I measured 13.81 with SC40 and 13.85 without (I have a secondhand second battery).

[Blknight.aus]

for the Foz.





1 ) What is the voltage at the cranking battery’s terminals. 12.8v @ about 12 degrees at 0630

2 ) Type of vehicle. SIII2.25D

3 ) What make and type of battery ( a model number will do ) N70Z x2 hardwired in parralell

4 ) When was the last time the vehicle was driven. Yesterday

5 ) How long was the last drive 30 minutes

6 ) Is this your day to day drive or a once a week vehicle daily driver

7 ) Alternator size 12v 35A

8 ) Is this your tow vehicle or other.does it all

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start )12.7v after 30 seconds on the glowplugs and about 5 seconds of cranking (rises to 13.8 in about 20 minutes) (alternator doesnt excite properly till 1000ish RPM is passed)

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive.[/B] 13.85v

[DavidB]

The first question will be more accurate the longer the vehicle's motor has been off, preferably 12 or more hours after the motor was last on.

1 ) What is the voltage at the cranking battery’s terminals.
12.2v (With SC80 connected)

2 ) Type of vehicle.
2000 Disco II Td5 Auto

3 ) What make and type of battery ( a model number will do )
Voltz Premium N87

4 ) When was the last time the vehicle was driven.
18 Hours Ago

5 ) How long was the last drive
30km

6 ) Is this your day to day drive or a once a week vehicle
Daily

7 ) Alternator size
120amp

8 ) Is this your tow vehicle or other.
Only vehicle

If you can, the following info would also be of interest.


9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start )
13.8 v


10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive.
13.6v

[Graeme]

1 ) What is the voltage at the cranking battery’s terminals: 12.58 (main, after recovery from door open) & 12.52 (aux - some accessories permanently powered) Batteries connected via Matson VSR.

2 ) Type of vehicle: TD5 D2 MY03 Oct 02 build

3 ) What make and type of battery ( a model number will do ): AC Delco S31-900MF (main) Remco RM12-80 (AGM aux)

4 ) When was the last time the vehicle was driven: More than 14 hrs ago

5 ) How long was the last drive: 45 mins

6 ) Is this your day to day drive or a once a week vehicle: everyday

7 ) Alternator size: 120A Nippon Denso

8 ) Is this your tow vehicle or other: All duties

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ): 14.54 @ 15 deg C (morning & stabilised about 45 secs after starting)

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 13.85 (45 min drive & fridge running off aux)

[Graeme]

I forgot to mention that on cool mornings I've seen up to 14.8 shortly after startup.

[drivesafe]

So far with 20 vehicle’s cranking battery’s stats post both here and on the other sites, the count is 3 = 70% or less, 3= 80 to 90% and 14 are 90% and better.

This is starting to show that the myth that no vehicle batteries will charge over 70% is just that, a myth, but lots more posting are coming.

[Disco_owner]

Another test I carried out Tim , since my Discovery hardly gets driven , I took the Champion battery out on "Wednesday" night and placed on battery charger for 12v "Trickle charge , this morning the battery had not reached it's full state of charge even thou it had been on charge for over 48 hours , the only way to force it to reach it's full charge state is to change the position of the charge to Rapid charge ( 12 v ) and only then the battery charger indicated that the battery was Full.

Battery Voltage Fully charged = 13.03 volts

Engine on Voltage accross the Terminal = 14.03 volts

with the battery Isolator ( Vsr )


hope this helps.

[pawl]

1 ) What is the voltage at the cranking battery’s terminals. 12.42V
2 ) Type of vehicle. 96 300 Tdi Discovery

3 ) What make and type of battery ( a model number will do ) Delkor M24 MF > 6yrs old

4 ) When was the last time the vehicle was driven. 20 hrs ago

5 ) How long was the last drive 30 mins

6 ) Is this your day to day drive or a once a week vehicle Day to day

7 ) Alternator size 100A

8 ) Is this your tow vehicle or other. Tow Vehicle as well as everything vehicle

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start )
14.45V
10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.36V

[justinc]

1 ) What is the voltage at the cranking battery’s terminals. 12.42V
2 ) Type of vehicle. 96 300 Tdi Discovery

3 ) What make and type of battery ( a model number will do ) Delkor M24 MF > 6yrs old

4 ) When was the last time the vehicle was driven. 20 hrs ago

5 ) How long was the last drive 30 mins

6 ) Is this your day to day drive or a once a week vehicle Day to day

7 ) Alternator size 100A

8 ) Is this your tow vehicle or other. Tow Vehicle as well as everything vehicle

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start )
14.45V
10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.36V

Sorry for the hijack, but I need to mention here that I have seen plenty of these Delkor units last 6 and 7 years. I fit only these now to LR's as they supply a direct replacement for D2 and Td5 Defender (31-900) that are as good as the OE Delphi one and the same dimensions.

JC

[pawl]

Sorry for the hijack, but I need to mention here that I have seen plenty of these Delkor units last 6 and 7 years. I fit only these now to LR's as they supply a direct replacement for D2 and Td5 Defender (31-900) that are as good as the OE Delphi one and the same dimensions.

JC

Hmmm. thanks Justin good to know. All I can say is the time it has spent in my Disco. I pulled it out of the missus second hand Pajjy after my 2 yr old century battery couldn't deliver the juice the starter wanted. So it was second hand when I put it in the 300 Tdi, don't know how long it was in the pajjy. Although I must add it is getting tired now starting at 4.30 am.

[p38arover]

Jeez! I'm lucky to get two years out of a Delkor in the P38A! I think it's because the alternator doesn't charge at a high enough voltage for Lead Calcium batteries.

The trouble is that it's hard to buy a non-calcium battery.

I've had the car for just over 7 years and I'm on my 4th (or is it 5th?) battery (including one red-top Optima). Yes, the alternator has been changed (to another standard item). The one in the Disco only lasted 12 months and it was replaced under warranty.

[Disco_owner]

Jeez! I'm lucky to get two years out of a Delkor in the P38A! I think it's because the alternator doesn't charge at a high enough voltage for Lead Calcium batteries.

The trouble is that it's hard to buy a non-calcium battery.

I've had the car for just over 7 years and I'm on my 4th (or is it 5th?) battery (including one red-top Optima). Yes, the alternator has been changed (to another standard item). The one in the Disco only lasted 12 months and it was replaced under warranty.

Ron , I too got tired of buying new batteries , so I bought a battery charger with 12V rapid or Trickle charge function , so Now I regularly take both batteries out and charge them until they reached their FULL charge state , well that's according to the Battery charger anyway , hopefully this will prolong the life of my batteries:)

[Lionel]

Answers in italics

1 ) What is the voltage at the cranking battery’s terminals. 12.63 (36 hrs after 100 Km run Temp 15 deg C after 8.7 deg overnight)

2 ) Type of vehicle. Defender TD5 reg Aug 2004

3 ) What make and type of battery ( a model number will do ) Supercharge MF31-931 5 years old! (no 2nd battery)

4 ) When was the last time the vehicle was driven. Saturday 19th

5 ) How long was the last drive 100 Km approx

6 ) Is this your day to day drive or a once a week vehicle Used every 2 to 3 days on average

7 ) Alternator size 120A

8 ) Is this your tow vehicle or other. No towing done recently

If you can, the following info would also be of interest.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 12.63v after opening door, 14.55v after engine running

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.32v

Cheers,

Lionel

[drivesafe]

Hi folks and thanks to all who replied.

I was trying to get 20 maybe 25 replies from all the forums I posted the poll on and as 15:00 this afternoon, I have 51 replies.

I’m now going to have to put a spreadsheet together to process all the info.

Once done, I’ll post up the results, but any one still wants to reply to the poll, I’m leaving it running.

Again thanks and BTW this site posted the most replies by a factor of 2:1 compered to the next largest site count.

[drivesafe]

Thanks to those who took part in the poll and I am not going to post up any opinions on the results, people can come to their own conclusions.

Anyway here is the initial results from 52 replies of the Cranking Battery Voltage reading are as follows :-

95% ( 12.6 ) or higher = 25

90% ( 12.5 ) or higher = 13

80% ( 12.42 ) or higher = 4

70% ( 12.32 ) or higher = 2

Lower than 70% ( 12.32 ) = 8

There is a lot more data to be sorted yet but this was the main aim of the poll.

The Highest reading was 12.95v and the lowest was 11.83v

A small number of the reading were taken less than 12 hours from the last time the motor was run so I will have to do some calibrating.

Again Thank you to all those who contributed.

[isuzurover]

So:
~ 48% of batteries charged to >95%
~ 73% of batteries charged to >90%

Sorry I haven't posted results yet.
So far I have:
12.73V after 6 hrs standing.
EXIDE N70EX in a IIA diesel with 40A Lucas Alt. (only battery)
Daily driver atm. No towing.
Will have more data from the IIA and the 110 after the weekend.

[drivesafe]

Thanks Ben and post up when your ready as I’m going to keep the poll running and just update it every so often.

Cheers

[awabbit6]

Here are my results with the auxiliary battery isolated. I will collect the data again on Friday with both batteries charging.

1 ) What is the voltage at the cranking battery’s terminals. 12.22V

2 ) Type of vehicle. 94 Disco Tdi

3 ) What make and type of battery ( a model number will do ) SuperCharge (?? Forgot to get the model number - will update)

4 ) When was the last time the vehicle was driven. 36hrs prior

5 ) How long was the last drive 25km

6 ) Is this your day to day drive or a once a week vehicle Daily driver

7 ) Alternator size 100A

8 ) Is this your tow vehicle or other. It's my tow vehicle, tractor, adventure bus and anything else you can think of.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 13.7V

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.15V (at idle)

[drivesafe]

Some more info from the poll, and there are still replies coming in.

Most but not all replies included the operating voltage, of the info supplied, only 6 had 14.5v or higher, nearly half the vehicles ( 23 ) were between 14 and 14.4v but more interestingly though, 21 were under 14v but most had a cranking battery SoC of higher than 90%.

Some additional info, and this was to be expected, 6 of the vehicles with cranking battery SoC of less than 80% were pre 2001, 2 were 2001 Jeeps and these also had operating voltages of just 13.9 Max, 1 vehicle was 2003 and the last was 2006.

Of the vehicle with 90% or better cranking battery SoC, 14 were 2002 or later, but 13 were pre 1999 and of these 4 were pre 1990.

This well and truly makes a mockery of the myth that you can’t charge a cranking battery over 70-75% SoC and it shows that the alleged problem probably never existed.

BTW, most of the vehicles with low cranking battery SoC were Landies:o

[scarry]

Ok,here's a couple of other brands,havent had a chance to do the LR's yet as they dont get used much,& the Puma is on Fraser for a couple of weeks.

1 12.56v
2 04 mitsubishi express 2litre petrol(LPG)
3 Supercheap gold EXG MF40b20df 380cca
4 36hrs previous
5 15k's
6 daily driver
7 dunno
8 doesn't tow anything
9 14.52v
10 14.23v after 20min run


1 12.59v
2 08 Hi-ace petrol 2.7litre petrol(LPG)
3 The furukawa battery co (OEM battery)
4 12 hours previously
5 60k's
6 daily driver
7 dunno
8 tows very infrequently
9 14.12v
10 13.39v after 30mins

Sorry,dunno the alternater sizes,i will look up & try & find out.

Meter used fluke 11

Hope the above helps

[awabbit6]

And here are the values with the auxiliary battery connected - identical conditions and same trip. (Cranking battery in red, aux in blue,)

1 ) What is the voltage at the cranking battery’s terminals. 12.30V, 12.57

2 ) Type of vehicle. 94 Disco Tdi

3 ) What make and type of battery ( a model number will do ) SuperCharge Gold 670cca (MF80D26R), Century 450cca (57)

4 ) When was the last time the vehicle was driven. 36hrs prior

5 ) How long was the last drive 25km

6 ) Is this your day to day drive or a once a week vehicle Daily driver

7 ) Alternator size 100A

8 ) Is this your tow vehicle or other. It's my tow vehicle, tractor, adventure bus and anything else you can think of.

9 ) What is the voltage at the cranking battery when you first start your vehicle ( cold start ) 13.9V

10 ) With the motor still running, what is the voltage at your cranking battery after a 30 minute drive. 14.09V, 14.09V (at idle)

[drivesafe]

Hi folks and the poll is now closed.

Thanks for all the replies, and while I had hoped to get 20 to 25 replies but there are some 61 replies and thats excellent.

Owing to some dubious one eyed comments made by Collyn rivers on a number of sites ( he is one of the worst protagonist promoting this 70% crap ) the poll results are being compiled by someone else and once the results are available I’ll post them up.

A little foot note, more than half the vehicles that had a cranking battery with a 70% SoC or less, were on this site.

Go figure?

Mind you, this site also had the largest response!

Thanks again folks

[rangeyrover]

A thousand thanks for this thread.
Thought I was going mad with the charging voltage OP of my Discovery 2 V8, which seemed low at 13.4V max, but also looks a characteristic of other Discovery 2 listed here.
I will post my results in a few days, for others reference, but I am currently topping them up using the charger, so will wait till I have used the vehicle a few times on alternator only.