Motorhome starter battery woes

cdjpb replied on 27/02/2021 09:46

cdjpb

Posted on 27/02/2021 09:46

Hi all, I wonder if anyone can help with the starter battery issues on my 2021 Roller Team T-Line 590.

The van has a Phantom Sentinel alarm and tracker fitted which I understand will take some power from the battery. As far as I know, there’s nothing else taking power from the starter battery (other than the vans internal systems).

The van is in storage at the mo so I can’t keep the van plugged into EHU.

I could see on the Phantom app that my starter battery voltage was discharging from 12.4v to 11.9v in about 2-weeks even with a 6w solar trickle charger connected. It’s had this charge/discharge cycle for 2.5 months.

So 2 weeks ago a dealer fitted a CSB2 for me which is connected to my 120w solar panel and now my battery discharges from 12.4v to 11.9 in about a week! And it seems to be having no effect even though the leisure battery is reading 13.6v and we’ve had 5 days of bright sun!!!

Any ideas what’s going on? The van starts but is my starter battery just dead as it’s failing to hold charge? Perhaps the regular charge/discharge cycle has killed it - but it’s only 3 months old! Or could the CSB2 be faulty?

Many thanks!

Moderator Edit:

Not sure why you posted this in the Caravan Section but I've moved it to the Motorhome Section.

7 replies

LLM replied on 27/02/2021 10:07

LLM

Motorhomer from Northumberland

Posted on 27/02/2021 10:07

I suspect that the CSB2 is doing its job and prioritising the charging of the leisure battery(s). it won't begin charging the truck battery until they are fully charge and the float voltage of 13.8 has been achieved for 24 hrs. Look at the CSB2 specification for more info.

1 person likes this

cdjpb replied on 27/02/2021 19:26

Member

cdjpb

Caravanner

Posted on 27/02/2021 10:07 by LLM

I suspect that the CSB2 is doing its job and prioritising the charging of the leisure battery(s). it won't begin charging the truck battery until they are fully charge and the float voltage of 13.8 has been achieved for 24 hrs. Look at the CSB2 specification for more info.

Posted on 27/02/2021 19:26

Thanks for your reply; I checked the instructions and when the leisure battery reaches 13.6v it’s supposed to transfer charge to the cab battery. The leisure battery has been at 13.6v for weeks! So either the charge isn’t getting through or the battery is discharging really quickly.

JollyKernow replied on 27/02/2021 20:40

Member

JollyKernow

Motorhomer from Devon

Posted on 27/02/2021 20:40

I have a 100w solar panel with a dual charge controller. You can adjust the charge percentage wise between each battery, so when in storage I set mine to 100% vehicle battery. It's a cheap chinese mppt controller that was £25 on ebay, 3 years later still working a treat.

LLM replied on 28/02/2021 09:14

LLM

Motorhomer from Northumberland

Posted on 27/02/2021 19:26 by cdjpb

Thanks for your reply; I checked the instructions and when the leisure battery reaches 13.6v it’s supposed to transfer charge to the cab battery. The leisure battery has been at 13.6v for weeks! So either the charge isn’t getting through or the battery is discharging really quickly.

Posted on 28/02/2021 09:14

You are correct re the voltage, 13.6 it is. Sorry for the typo. I'm not aware of being able to adjust the CSB2 as JK suggests. It's quite difficult to mess up the installation of the unit as it is simply a three pin plug. I suggest you get the installer to check out the unit and what they have done.

cyberyacht replied on 28/02/2021 09:34

Member

cyberyacht

Motorhomer from Hampshire

Posted on 28/02/2021 09:34

A battery master pulls charge from the leisure battery to the engine battery when the voltage differential drops sufficiently to trigger the devise, usually somewhere between 0.5v and 1V. Depending on the level of charge in the engine battery, it's not dependant on the leisure battery being fully charged AIUI.

LLM replied on 28/02/2021 10:26

LLM

Motorhomer from Northumberland

Posted on 28/02/2021 09:34 by cyberyacht

A battery master pulls charge from the leisure battery to the engine battery when the voltage differential drops sufficiently to trigger the devise, usually somewhere between 0.5v and 1V. Depending on the level of charge in the engine battery, it's not dependant on the leisure battery being fully charged AIUI.

Posted on 28/02/2021 10:26

Yes. Different bits of kit work in different ways and to different protocols. You make your choice and pays your money.