What voltage and power can be applied over relay out out on Cerbo GX? Assummed that the relay output is passive contact. Is the relay out a pulse or can it hold? Is external relay to power consumer required?
asked
Cerbo Gx relay outputs
Hi, here are the updated details : https://www.victronenergy.com/live/venus-os:start#comparison_table
Any that knows these details?
Hi @Lvaarli
it's a signal relay, I would not put more than 1A through it.
Max voltage AC: 230V (AC rating tbd, will update later)
Max voltage DC: 30V, for low current (below 1A) you can go to 48VDC also
Hi @Lvaarli
I will get back to you when I have an official answer.
Hi, Any update from victron on this topic?
Is it possible to setup this relay output based upon Battery SOC? Since intended use is to turn a load on off. Thanks for swift reply.
I'm using the relay 1 output on my Cerbo, to turn my boat's electric hot water heater on and off. It's turned on and off based on battery SOC, DC load and time of the day using the generator start/stop function and inverse logic (wired to the NC contact of the relay). This way the solar tops the batteries to 90%, then turns the hot water on and leaves it on till late afternoon when there is no excess solar input. It'll also turn the hot water off when there are any large loads on the system.
I use the built in relay to switch a larger 230VAC relay with a 24V coil and use a protection diode (a normal diode and a zener) arrangement to ensure the field break down when turning off the big relay doesn't fry the little one.
The generator control function is quite configurable, so this should be able to do what you want.
Any questions, please ask.
P.S. Victron, I'd love to see dedicated hotwater control functionality in the Cerbo, with a few more advanced features like multiple temperature set points for different SOCs.
P.P.S. It would also be great to be able to use relay 2 for anything other than manual switching. This seems to be useless?
I have this same set up, but without the protection diodes and I think I've fried the relay in the Cerbo. See my post here https://community.victronenergy.com/questions/158046/wiring-for-relay-on-cerbo-gx.html
I'd like to resolve the issue with my set up, would you post a wiring diagram for yours?
Check out the second last paragraph of this: https://www.durakoolrelays.com/information/technology/layman-s-guide-to-coil-suppression/
That's the arrangement. Unfortunately I didn't record the exact specs of what I used, but it was all off the shelf at my local electronics shop. I've had this setup running for ~2.5 years now with no issue, so it seems to be working well.
You can have a Cerbo Relay 1 actuate based on SOC, just review the manual section on auto starting a generator. I know you are not starting a generator, but it's the same functionality. My understanding is that Relay 2 can not be used in this way.
I would also like to control the water heater with the relais.
In my use case I could switch on the water heater before I leave home going to the boat so the water is hot when I arrive at the boat.
Therefore, I would love to give relais1 or 2 a custom name and also be able to switch the relais from the remote console on vrm
Wow? The relais cannot be used remotely? I was planning on using relais 2 for remotely starting campervan and engine heating. Is that mot possible?
Hi.
I would also like to connect a hot water System to a remote on/off relay.
Do you mind sharing a wiring diagram on the best way to do this? Will I need a diode.?
I assume I’m need an external relay, is there a suc six you would suggest?
Many thank
Lionel
Have you got any further with this project? I'm trying to do the same.
I can find a DC controlled AC relay that will work on 12v, but the CerboGX only seems to output about 30mv, so I assume I will need a 30mv control voltage relay to switch 12v through the AC relay. Trouble is, I can't find a relay with such a low control voltage.
The specs on the Cerbo GX relay have been given in the other thread you have and are easily found on the Cerbo GX datasheet at
https://www.victronenergy.com/upload/documents/Datasheet-Cerbo-GX-GX-Touch-EN.pdf
For 12VDC the relays are good for 6A (up to 30V DC). As mentioned elsewhere in this thread make sure you have flyback diode on any relay/contactor coil driven off the Cerbo GX relay.
Check out the second last paragraph of this: https://www.durakoolrelays.com/information/technology/layman-s-guide-to-coil-suppression/
I want this function as well. I find the support for the Relay controls to be very poor. There doesn't seem to be any way to switch a relay from the Color Touch screens except down in the menus. I want to be able to label the relay, and have it show in the VRM portal and also on the color touch screens on one of the pages. Should be able to do the same for any remotely controlled relays such as the relay on the BMV-712 when that device is connected.
