Battery Bank Switch Relay Timer Base ( DC Isolator)

abeezar

Hi

I have a Solax AC Inverter with a Solax bank of batteries. The limitation of the inverter is that I cannot add more than 3 batteries ( single phase).
It allows parallel mode - where an additional AC Inverter(salve)/Batteries can be installed.

I want to avoid installing another  AC Inverter, however, be able to buy another Battery ( Master) and be able to switch with something like a DC Relay manually with a Timer Switch or through an app.

Can anyone recommend a Relay that can meet the requirements?

Thanks and Regards

Solarchaser

You can get 240v ac relays, that is the coil that is the switch activation is 240v ac, as for what's being switched, a relay doesn't care as its just a switch, so ac or dc doesn't matter, as long as its current carrying capacity is enough.

Why I say this, rather than answering the question you asked, is because if you have an ac switch activation then you can use a WiFi or timer mains plug to do it.

However not having a solax myself I can't comment on how the bms works, and so you may be able to switch the battery, but not its management potentially 

abeezar

Solarchaser said:

You can get 240v ac relays, that is the coil that is the switch activation is 240v ac, as for what's being switched, a relay doesn't care as its just a switch, so ac or dc doesn't matter, as long as its current carrying capacity is enough.

Why I say this, rather than answering the question you asked, is because if you have an ac switch activation then you can use a WiFi or timer mains plug to do it.

However not having a solax myself I can't comment on how the bms works, and so you may be able to switch the battery, but not its management potentially 

Thanks.  
I want the AC Inverter to talk to another set of batteries. I presume between Inverter and Batteries its DC Voltage. 
So its like turning off one battery bank system and then switching to another system - such that the inverter now talks to 2nd system - not sure if the AC inverter needs to reboot.

Solarchaser

I'd suggest that there will be some sort of communication cable as well as the DC so that the battery management system can tell the inverter to limit current when the battery is almost full or empty.

That's the way it works on sofar and lux systems.

If you have 3 batteries and are adding 1, id suggest you have 2 that are permanently connected and the switch is purely between the last 1 and the additional one, this should mean that the inverter wouldn't need to shut down on switch over, but thats just theory, as I dont have a solax.

Looking at this listing for an accessory kit, suggests there is a comms cable
https://www.ebay.co.uk/itm/175011255059?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=1y3cwZYpTzi&sssrc=2349624&ssuid=DtbsXk1pRsq&var=&widget_ver=artemis&media=COPY

Solarchaser

BTW an Internet search suggests you can have 4 batteries if it's a solax triple power.
I searched solax adding battery, and the second link down is an installation guide which includes adding 2-4 batteries

abeezar

Solarchaser said:

BTW an Internet search suggests you can have 4 batteries if it's a solax triple power.
I searched solax adding battery, and the second link down is an installation guide which includes adding 2-4 batteries

3 Phase - 4 batteries , 1 Phase max 3 batteries

1961Nick

If it could be done without an inverter reset every time the relay switched over, you'd then have the problem of one battery being massively out of sync with the other two.

I'd bite the bullet & buy another inverter rather than invest in switchgear that probably won't work satisfactorily. 

ispookie666

@abeezar
Might be easier trawling various off grid/motor home/sailing/boating groups.