Use Z-Uno as a switch?

[cmpts_cmp]

Hi,

Please see attached (quickly done) drawing.

I have two 12v leisure batteries. I'd like to use an automated process to switch between charging. So, if battery #1 falls below 11v for example, I could use a z-uno to switch over the charging to that battery. The charger will charge until the battery is full and then it uses a "float" charge to keep it topped up. So, that battery is ready to be used when the other battery now falls below 11v, and repeat.

Can the Z-Uno handle this sort of switching with a 12v 110Ah battery or is the current too high for it and some additional board is required that the Z-Uno controls? If the latter, what would this look like?

Chris

[PoltoS]

Z-Uno do not have relays - only 3V digital outputs. You will need to connect relays to digital pins. Those relays should survive the charging current of your battery.

You can check examples on https://z-uno.z-wave.me/examples or See picture in this tweet https://twitter.com/zuno_zwave/status/1 ... 72352?s=19

[cmpts_cmp]

Awesome. Cheers!

[cmpts_cmp]

Can you recommend any 12v 10A relays? Any good manufacturers?

[p0lyg0n1]

Hi,
We use relays from FINDER, OMRON and TE Connectivity(AXICOM). If you want to do your own PCB for this project you can look to this brands and select one that meets your requirements (size, maximum current, coil voltage etc). To control relay from Z-Uno pin you need a transistor(for ex. FET IRF7455) and special fast switching diode(for ex. FR157) to prevent transistor from induction voltage of relay. If you don’t want to dig deeper in schematics you could use Z-Uno Shield(it already has 4 transistor to control 12v load) or you can use some shields/modules from sparkfun/adafruit/aliexpress:
https://learn.adafruit.com/adafruit-pow ... eatherwing
https://www.sparkfun.com/products/15093
https://m.ru.aliexpress.com/item/329973 ... 7752747515