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I'm having problems wiring up the programable relay on a Cerbo GX device.
I'm using the relay to control an electric water heater that will turn on when there is excess power available in the system.
I wired it up the DC side and the relay in the Cerbo seems to have fried. It's stuck on "NO". Wondering if anyone can suggest where I've gone wrong?
The Cerbo relay is wired to a larger DC/AC relay that the power for the immersion heater runs though.
See diagram bellow:
As per the other thread with my post that you found, it's probably the field breakdown from the big relay that's fried it. Unfortunately you'll need to get the Cerbo repaired, then try again with a protection diode. The setup is just a zener and a normal diode in series across the coil at the relay.
https://www.durakoolrelays.com/information/technology/layman-s-guide-to-coil-suppression/
possibly the current needed to latch the relay? Or the arcing that happens on opening and closing of the contact.
https://www.victronenergy.com/live/venus-os:start#comparison_table
I suspect a cost effective SSR was used, find yourself a good quality one and it'll likely work fine - however it will cost about 15x what the cost effective one cost.
The Internet is awash with cheap and nasty solid state relays.
Did you find out why your relay fried? I want to do exactly the same set-up with the Cerbo's relay 2 or one of the quattro's relays but I'm confused if a protection diode is required.
I'm already using Cerbo relay 1 wired directly to the quattro's aux 1 (and on to AC out 2) without any protection diode (should I put one?) and its working flawlessly.
I don't want any protection diodes if they are redundant.
F.
I was looking at your drawing again. Why do you have 48vdc going from your battery to your relay when the relay says 32v max?
F.
