SLA charging voltages?

[JockandRita]

Can those in the know help please?
I have installed 4 x Varta LFD 90A Sealed Lead Acid Batteries, but not 100% sure what setting to use on the Sterling B2B.

As you can see from the photo below, "Sealed" (which is the setting they are on), has a much lower charging voltage than "Open"
Although sealed, they are still wet lead acid batteries, so not sure re the correct setting.

Obviously, I don't want to under charge the batteries, which would soon ruin them, just as overcharging (boiling them dry), would soon do the same, so I need to sort out the correct setting for the best results.

Cheers,

Jock.

 

[paddymcc]

I've got Numax sealed lead acid which the previous owner bought in 2012. They have been charged at 14.4V over 9 years and still have a reasonable capacity. I think 13.4v is a bit low, maybe check with Sterling?

 

[JockandRita]

I think 13.4v is a bit low, maybe check with Sterling?

Thanks Paddy. I also think 13.4v is too low.

Raul, autorouter, and Lenny HB. What are your thoughts please?

Cheers,

Jock.

 

[autorouter]

Welcome to the Sterling User Interface, one of the worst I have ever seen - and I've seen plenty. It doesn't work like you are thinking.

The left column (black) shows what Battery Type preset the B2B is set for. The preset voltages are listed in the manual - if you don't like them, you can set it to 'Custom', then follow the procedure to change them.

The next column (green) shows the input voltage (alternator voltage if engine running, or starter battery voltage if not). Nothing to do with the preset settings column at all.

On the right, the green column shows the output voltage (to the leisure battery). The black column shows the status lights, which indicate errors and B2B state settings.

 

[JockandRita]

Thanks autorouter. I am up there with the instructions and how it works. I'm just not convinced that "Sealed" at 13.4v is the right setting for sealed wet lead acid batteries.

I have the unit set up on option 2), ie, ignition feed.
When the Gels were fitted, I used the Gel II setting for 14.4v.

Once I know what the correct charging voltages for 12v SLAs are, I can work from there. Any research on the internet, refers me to those small batteries you find in house alarm installations as standby batteries. Like this one.

Cheers,

Jock.

^{_{Subscribers  do not see these advertisements}}

 

[andy63]

Hi jock...here's a link to one manufacturers take on charging sealed lead acid batteries..
I think it ties in with your thoughts that your charging voltage could be raised a bit...13.2 to13.4 I think is the recommended max float voltage..
The sterling bat to bat you have certainly doesn't have a easily used interface but it is very flexible and under user settings you should be able to pretty well customise whatever charging voltages you want..
Unfortunately I no longer have access to the instructions so can't help with the procedure..

Complete Guide On How To Charge A Lead Acid Battery - Power Sonic

Power Sonic's guide on how to charge a lead acid battery includes charging methods, characteristics & how to charge in series and parallel

www.power-sonic.com

Andy

 

[Raul]

Thanks Paddy. I also think 13.4v is too low.

Raul, autorouter, and Lenny HB. What are your thoughts please?

Cheers,

Jock.

Here is my two penny worth,
A lead acid starts to gas at 13,5v. Sealed means you can’t replace the loss of electrolyte. Some, only few, can, and have a recombination of gases built in, to reduce the electrolyte loss. That’s agm‘s gell’s and some flooded sealed. The clue is in the float charge value given by the manufacture of each battery. A B2B that can’t do 3 stage charging, to protect the battery, it will have to settle at highest float value. In this case, a sealed flooded without recombination of gases float without gassing will be 13,5v max. However, it will take a long time to charge at this voltage, but, it will be quite ok for partial charge or top ups. Personally, I would opt for 13,8v for a B2B in this instance, because I will not be forever on the road, and will not make the battery to gas to much. Besides, the so called sealed flooded, I have opened quite few to add distilled water. They are not really sealed, not all of them. The ones with the eye can be opened to add water if needed. Just remove the sticker to reveal the 6 caps.

 

[JockandRita]

Some, only few, can, and have a recombination of gases built in, to reduce the electrolyte loss. That’s agm‘s gell’s and some flooded sealed.

Thanks Raul. These are Varta LFB 90A SLAs, (now superseded), as recommended by the (much respected (but sadly departed) Allan, of A & N Caravan Services, as a good choice of fit and forget for an internal installation, (garage in our case), because of their construction regarding recombination of gases, with a lower venting requirement to Gels or AGM.

"If you need a battery that is safe inside the vehicle without a vent, then we think the Varta LFD90 is the only option, safer even than Gel or AGM."

Battery Technology Advances mean big savings and better batteries for Caravans/Motorhomes

The best Leisure Battery is also one of the cheapest - Powerframe Varta LFD90 and Bosch L5. A Deep cycling and Starter battery in one.

www.aandncaravanservices.co.uk

A B2B that can’t do 3 stage charging, to protect the battery, it will have to settle at highest float value. In this case, a sealed flooded without recombination of gases float without gassing will be 13,5v max.

The Sterling B2B Is a 4 x stage charger, as displayed in the photo above, ie, bulk, absorption, conditioning, and float.

Personally, I would opt for 13,8v for a B2B in this instance, because I will not be forever on the road, and will not make the battery to gas to much.

Thanks again.

Cheers,

Jock.

 

[autorouter]

A B2B that can’t do 3 stage charging, to protect the battery, it will have to settle at highest float value.

This B2B has multi-stage charging (IUoUoU). The settings table for 'Sealed' shows Absorption 14.40V, Conditioning 14.15V, Float 13.60V.

 

[Richard n Ann]

What about variation in ambient temperature? That changes the charger voltage on ours I think

^{_{Subscribers  do not see these advertisements}}

 

[JockandRita]

This B2B has multi-stage charging (IUoUoU). The settings table for 'Sealed' shows Absorption 14.40V, Conditioning 14.15V, Float 13.60V.

That sounds good to me. Just found that on the Sterling 1260 B2B instruction PDF. My printed version is in the MH, so I couldn't reference to it. Thanks for the reminder.

What about variation in ambient temperature? That changes the charger voltage on ours I think

I have the battery temperature probe connected, which takes care of that.

Thanks all for your contributions. Much appreciated.

Cheers,

Jock.

 

[autorouter]

What about variation in ambient temperature?

There is an option for connecting a wired temperature sensor to fit on the battery.

 

[Raul]

This B2B has multi-stage charging (IUoUoU). The settings table for 'Sealed' shows Absorption 14.40V, Conditioning 14.15V, Float 13.60V.

Good to know, I didn’t look for the B2B spec, I just commented on the OP post as presented. Those voltages look good for a sealed anyway.

 

[JockandRita]

Here's another question, if I may.

Bearing in mind the multi charging voltages for the "Sealed" setting on the B2B, (14.4v, 14.1v, and 13.6v), what setting should I choose for the onboard CBE charger, and 2 x Votronic MPPT controllers, ie, Lead Acid, or Gel?


I am thinking that the Gel setting would be closer to the voltages needed for the SLAs.........................but would that be right, or not?

Cheers,

Jock.

 

[JockandRita]

I am thinking that the Gel setting would be closer to the voltages needed for the SLAs.........................but would that be right, or not?

Anyone able to confirm please, as there is no setting for SLAs batteries on either the onboard CBE charger, or the solar controllers?

Cheers,

Jock.

^{_{Subscribers  do not see these advertisements}}

 

[andy63]

Anyone able to confirm please, as there is no setting for SLAs batteries on either the onboard CBE charger, or the solar controllers?

Cheers,

Jock.

Did you check out the link I posted in an earlier post jock.. it pretty well covers all the bases on charging sealed lead acid batteries..
A fast charge voltage of 14.7v and a float of around 13.8v are the voltages recommended I think..

Andy

 

[JockandRita]

Did you check out the link I posted in an earlier post jock.. it pretty well covers all the bases on charging sealed lead acid batteries..
A fast charge voltage of 14.7v and a float of around 13.8v are the voltages recommended I think..

Andy

Apologies Andy, I must have missed that one earlier. Thanks for the reminder.

All settings re solar and 240v charging are on lead acid setting, with the B2B on a SLA setting. I am happy now, knowing that I'm neither going to cook, nor undercharge, causing premature failure of the batteries.

Thanks to all,

Jock.