Is Solar charging my batteries at 14.81-87v too much?

[Star-Lord]

Solar charging car batteries (x 10 at 95Ah to 14.87v and setting off the gas alarm! The batteries were bought two summers before Covid and hold charge nicely. This has happened before - only really in very hot weather. The batteries are LX Supreme with a Green dot in a glass bowl on top to show battery health- they all look healthy and all terminals are looking good (professionally fitted). I read somewhere (I can’t find where) that charging over 14.6 on Solar is bad? My MPPT controller says it’s Bulk charging. So, I switch off gas sensor and wait an hour or so then put it back on and all is good. Does anyone see a problem with any of this?

 

[noelex]

14.87v for that type of battery in hot weather is way too high.

You need to adjust the settings on the solar regulator or replace it if the regulator is allowing this high charging voltage despite appropriate settings.

The regulator may be initiating an equalisation cycle In which case you need to find if this appropriate for your battery.

The best guide for the correct bulk/absorption voltage is from the battery manufacturer, if you can find this information. This needs to be adjusted for temperature either automatically by a temperature sensor or manually.

 

[Star-Lord]

14.87v for that type of battery in hot weather is way too high.

You need to adjust the settings on the solar regulator or replace it if the regulator is allowing this high charging voltage despite appropriate settings.

The regulator may be initiating an equalisation cycle In which case you need to find if this appropriate for your battery.

The best guide for the correct bulk/absorption voltage is from the battery manufacturer, if you can find this information. This needs to be adjusted for temperature either automatically by a temperature sensor or manually.

It seems you need to attach a computer to it to adjust the settings (it a pre app version - or if an App came with it in 2014 I never knew). Any suggestions for a temporary’fix’ till I can get it sorted in September? I have two MPPT controllers (one for batwing and one for arch). I could just disconnect these 4 wires? (To limit solar input)

 

[Star-Lord]

Back down to 13.76v now - it only goes up to 14.8v for an hour or so. I have put the bat wings down. And I could throw a towel over the ones on the arch (there are 3 130w on the arch so if I covered on it should cut down the juice.

 

[PaulRainbow]

You need one of these:

VE.Direct Bluetooth Smart dongle - Victron Energy

No point covering panels.

 

[Star-Lord]

You need one of these:

VE.Direct Bluetooth Smart dongle - Victron Energy

No point covering panels.

Thanks Amazing.

 

[jamie N]

It could also be that you might just check the 'real' voltage with a DVM, against the indicated voltage, then make a decision.

 

[Star-Lord]

It could also be that you might just check the 'real' voltage with a DVM, against the indicated voltage, then make a decision.

Volt meter reads similar to battery monitor. The problem only arises after running engine (to change anchorage spot in the same bay or for hot water - too hot now to worry about hot water!) or when I’m in the marina for a couple of nights once a month to ‘boost batteries’ on shore power. So it is not the solar ‘alone’ causing the extra juice. I will be getting an Electrician to have a look in Malta in September.