Newbie...Trojan t105

[WotEver]

Have you actually done any testing to quantify your CURRENT battery capacity rather than the theoretical 'as new' capacity ?

Good point. Well over a week ago I suggested the following which would be a far better use of OP's time than copying and pasting American web sites.

 

When you get the batteries nominally to 100% (it doesn't appear that you've yet done so) you can discharge to 50% on the SmartGauge and note Ah supplied to do so as indicated on the Ah counter. Multiply that by 2 and you have your capacity.

[MtB]

Your right there, a glorified voltmeter...

 

Performed charge and after hitting 100% on Smartgauge, it took four hours to reach tail current of 4.75 amps,then a further 2 hours equalization charge and finally all specific gravities read 12.85...... 19.2 ah taken out over night....tv etc. Smartgauge 87% .... the voltage read 12.63 on the Bmv and 12.65 on the Smartgauge. The Smartgauge dropped 3% in 0.4 ah..Come on that's unreal.

 

 

What are you using to measure that?

 

As I understand it the electrolyte is 1,277 on a fully charged, unsulpated battery. Do I have that wrong too?

P.s. I presume you mean 1.285

[cuthound]

What are you using to measure that?

 

As I understand it the electrolyte is 1,277 on a fully charged, unsulpated battery. Do I have that wrong too?P.s. I presume you mean 1.285

Depends on the type of battery and what is intended to support. Many will have a fully charged sg of 1.265, but some are higher.

 

The old open cell lead lined wooden box type flooded batteries used in telephone exchanges used to have a fully charged sg of only 1.215, to ensure long life from the plates.

[Alan de Enfield]

 

 

 

 

As I understand it the electrolyte is 1,277 on a fully charged, unsulpated battery. Do I have that wrong too?

 

 

From 'Boating Australia' for FLA

 

Edited February 17, 2017 by Alan de Enfield

[WotEver]

 

As I understand it the electrolyte is 1,277 on a fully charged, unsulpated battery. Do I have that wrong too?

 

P.s. I presume you mean 1.285

No, you don't have that wrong. OP appears to have magically increased the relative density of his electrolyte.

 

And yes, he must mean 1.285. Even 98% pure H2SO4 has a relative density of 1.84, so he can't mean 12.85

 

From 'Boating Australia' for FLA

 

Not relevant for T-105s. 1.277 is their fully charged RD.

[MtB]

Depends on the type of battery and what is intended to support. Many will have a fully charged sg of 1.265, but some are higher.

 

The old open cell lead lined wooden box type flooded batteries used in telephone exchanges used to have a fully charged sg of only 1.215, to ensure long life from the plates.

 

 

Aha!

 

I didn't realise it varied from battery model to model.

 

The OP has Trojan 105 batteries according to the thread title. I've an idea my 1.277 came from the Trojan specs so 1.285 still seems an unfeasibly high result

[WotEver]

Absolutely. 1.277 for T-105s.

 

http://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdf

[MtB]

Absolutely. 1.277 for T-105s.

 

http://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdf

 

 

Thanks!

 

Can you come up with a figure for my Trojanoids perhaps? They are Yuasa Pro Spec DCB105-6ET batteries.

 

I've tried to find out and failed, which is why I used the Trojan figure, believing all batteries were the same. Now I know otherwise and am wondering what SG they are supposed to be.

It might turn out that all my furious equalising trying to get them up to 1.277 was futile and pointless!

[WotEver]

Can't find any worthwhile specs for the Yuasas, even their own spec sheet says little - it's more about the physical attributes.

Edited February 17, 2017 by WotEver

[nicknorman]

 

 

Aha!

 

I didn't realise it varied from battery model to model.

 

The OP has Trojan 105 batteries according to the thread title. I've an idea my 1.277 came from the Trojan specs so 1.285 still seems an unfeasibly high result

I would imagine OP has simply not corrected the gravities for temperature. It would be quite feasible to get 1.285 at this time of year - but of course the figure is pretty meaningless unless you correct it to 80F. In fact if the batteries are fairly cold, 1.285 is not high enough to be fully charged. 5C would mean subtracting about 16 points making the 1.285 into 1.269 (which I suppose if fairly close to fully charged).

 

I'd say the gravity for the trojanoids is likely to be the same as the real thing, but we can't be sure. Maybe the supplier could tell you?

Edited February 17, 2017 by nicknorman

[WotEver]

In fact if the batteries are fairly cold, 1.285 is not high enough to be fully charged. 5C would mean subtracting about 16 points making the 1.285 into 1.269 (which I suppose if fairly close to fully charged).

They're probably still a bit sulphated.

[Leon 12]

Sorry for the point in the wrong place. 1.285

 

I am just going to go with voltage on recharging, when It drops I will recharge. I do not heave any confidence in Smartgauge what so ever... sorry if that gripes a few folks. All cabling is 70mm sq now.I changed all interconnects. gave all the posts a good fettle applied petroleum jelly to protect.

 

Trojan recommend 16.2 volts for equalization......are there any chargers that can give that voltage?

[nicknorman]

Sorry for the point in the wrong place. 1.285

 

I am just going to go with voltage on recharging, when It drops I will recharge. I do not heave any confidence in Smartgauge what so ever... sorry if that gripes a few folks. All cabling is 70mm sq now.I changed all interconnects. gave all the posts a good fettle applied petroleum jelly to protect.

 

Trojan recommend 16.2 volts for equalization......are there any chargers that can give that voltage?

The Smartgauge has its limitations, but is pretty good at telling you when to recharge, presuming you've installed it correctly. But if you want to make life more difficult - up to you! I suspect you will notice that it is trustworthy once you have done a proper discharge and noted the Smartgauge reading vs the zero load voltage (having run around turning everything off and sitting in the dark for a while whilst the battery voltage stabilises, then forgotten to turn the fridge back on etc)

[WotEver]

 

I am just going to go with voltage on recharging, when It drops I will recharge. I do not heave any confidence in Smartgauge what so ever... sorry if that gripes a few folks

I doubt very much that anyone will care if you choose to make your life more difficult. It's not their time and batteries that you'll be wasting.

[cuthound]

Thanks!

 

Can you come up with a figure for my Trojanoids perhaps? They are Yuasa Pro Spec DCB105-6ET batteries.

 

I've tried to find out and failed, which is why I used the Trojan figure, believing all batteries were the same. Now I know otherwise and am wondering what SG they are supposed to be.It might turn out that all my furious equalising trying to get them up to 1.277 was futile and pointless!

Try asking them via this link.

 

http://www.yuasa.co.uk/contacts/

[Leon 12]

Hello, what effect does temp have on SOC, ie 12.60 volts at 20 degrees. I understand there are different views on this matter. Any advice welcome.

[WotEver]

Hello, what effect does temp have on SOC, ie 12.60 volts at 20 degrees. I understand there are different views on this matter. Any advice welcome.

The measured Relative Density increases as temperature drops. Readings are generally correct at 25C so every degree below that needs to be compensated for. Your refractometer should give you a temperature compensation figure. Rolls batteries suggest using the formula Correction factor = (0.595 x Cell Temp ºC 12.5) / 1000

 

T-105 User Guide: http://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdf

 

Edited to add user guide

 

Here's a table http://support.rollsbattery.com/support/solutions/articles/208145-specific-gravity-temperature-correction-factors

Edited February 18, 2017 by WotEver

[nicknorman]

The measured Relative Density increases as temperature drops. Readings are generally correct at 25C so every degree below that needs to be compensated for. Your refractometer should give you a temperature compensation figure. Rolls batteries suggest using the formula Correction factor = (0.595 x Cell Temp ºC 12.5) / 1000

T-105 User Guide: http://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdf

Edited to add user guide

Here's a table http://support.rollsbattery.com/support/solutions/articles/208145-specific-gravity-temperature-correction-factors

Im not sure that was the question. I think it was "what is the correlation between temperature and rested no-load voltage at a given SoC".

 

And I think the answer is "not a lot". ie the rested zero load voltage doesn't change much with temperature. Of course a cold battery will be more sluggish at converting chemicals to current and so for a given significant load, the voltage will reduce more quickly for a cold battery. But that isn't exactly what you asked.

[MtB]

Im not sure that was the question. I think it was "what is the correlation between temperature and rested no-load voltage at a given SoC".

 

 

 

I read it slightly differently. I think it was "what is the correlation between temperature and SoC for a given rested no-load voltage?"

[WotEver]

Im not sure that was the question.

Reading it again I agree

 

I read it slightly differently. I think it was "what is the correlation between temperature and SoC for a given rested no-load voltage?"

Same answer as Nick gave. Not much.

[mross]

I think he is confusing SG with volts AND got the decimal point in the wrong place.

[WotEver]

And doesn't trust Smartgauge on discharge.

 

A little knowledge and all that...

[MtB]

Yesterday out of curiousity I cross checked my Smartgauge reading with a battery voltage Vs SoC chart.

 

Battery voltgage 24.4v after two hours at rest, Smartgauge reading 55%. Seems about right.

 

The interesting thing was despite all my equalising, it only took 27AH to get from 100% Soc (1% tail current) last week down to 55% SoC.

 

Looks like my new(ish) Trojanoids remain goosed.

[WotEver]

Yesterday out of curiousity I cross checked my Smartgauge reading with a battery voltage Vs SoC chart.

 

Battery voltgage 24.4v after two hours at rest, Smartgauge reading 55%. Seems about right.

 

The interesting thing was despite all my equalising, it only took 27AH to get from 100% Soc (1% tail current) last week down to 55% SoC.

 

Looks like my new(ish) Trojanoids remain goosed.

Are you still using that broken Smartgauge?

 

Try the other one. Seriously, if the one you have is reading 0.3V high then that's more than a 10% SoC discrepancy.

[MtB]

Are you still using that broken Smartgauge?

 

Try the other one. Seriously, if the one you have is reading 0.3V high then that's more than a 10% SoC discrepancy.

 

 

Yes still using the dodgy Samartgauge, but the 24.4V value is obtained from the BMV702 which agrees with my multimeter. I rarely look at the Smartgauge voltage.

(My other smartgauge is in the other boat in Rugby and a series of unexpected obstacles have prevented me driving up to get it.)