New battery

[charliesgrandad]

Just purchased new leisure batteries, and it says they are sealed maintenance-free but do have vent holes, do I set my Solar controller to vented or sealed?

 

[autorouter]

Which solar controller is it? Are the batteries flooded, ie liquid acid, or are they AGM or Gel? All of these types can be 'sealed' - they don't produce much gas in normal charging, and all have a valve that releases if there's excessive overcharging and gassing but not otherwise.

 

[charliesgrandad]

They are liquid acid and they do have a very small breather hole on the end of the battery the controller is as photo

 

[Blue Knight]

On the PCM 2012 you need to make sure that the 'wet' setting is selected which has the 14.3v bulk charge and a 13.2v float charge.

You should select the sealed option on the controller but I would also make sure that the batteries have vent tubes connected too - just in case.

 

[charliesgrandad]

On the PCM 2012 you need to make sure that the 'wet' setting is selected which has the 14.3v bulk charge and a 13.2v float charge.

You should select the sealed option on the controller but I would also make sure that the batteries have vent tubes connected too - just in case.

Whilst waiting for a response on this thread I messaged Tayna who I purchased them from asking if I should remove the transit plugs from both ends of the battery and what to set my controller to ,this is there reply "No you can remove 1 which is adequate for venting - Please set it to vented."
So now I am a bit confused

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

 

[berni109]

Sounds like normal liquid acid batteries. Vents are connected internally so removing one transit vent plug is ok. I would ensure that there is a pipe connected to the vent and terminating outside into the open air. Nothing to stop u using a tee connector so only 1 pipe to outside air.

 

[Stealaway]

Nothing to stop u using a tee connector so only 1 pipe to outside air.

Buy the fitting and tube from B&Q, other wise they are horrendously expensive

 

[autorouter]

MPPT controllers like this one will have a multi-stage charging process. The first stage charges at full amps, with the voltage slowly rising, until it reaches the 'absorption voltage' limit. It then switches to constant voltage mode, with the volts staying at the absorption voltage, and the amps slowly reducing until a preset limit is reached. The controller then decides the battery is fully charged, and switches to 'float mode', which keeps the battery topped up without overcharging.

Different battery technologies have slightly different absorption and float voltages, ie different charging profiles. Ideally you should look up the required profile from the battery manufacturer's website, and match it to the nearest charging profile of your MPPT controller. The battery supplier probably doesn't know your controller, and the controller manual might not cover all possible battery technologies.

So what brand/type of leisure battery is it?

 

[autorouter]

Looking at the data sheet for the controller

https://cdn.enfsolar.com/z/pp/rzj60d2fce7014fe/5693784dbf349.pdf

The absorption voltage is constant at 14.3V (they call it the bulk voltage for some unknown reason), so no choice there. 14.3V sounds about right for wet (flooded) batteries like yours, but not much good for AGM or Gel which need 14.6 or 14.8V.
The float voltage is a choice between 13.2V and 13.4V - I'd go for 13.4V, so the 'Sealed' profile is the one required.