I have a temperature sensor connected to a MP2 GX and I would like to control the relay onboard.
I see that you can’t control the relay via Node Red BUT it should be possible using an Assistant.
Is there anyone out there who knows how?
I hope to then control heater pads on my 5kw LFP campervan battery.
A huge thank you in advance!
Inverter on board relays are controlled using assistants and ve configure.
You can open ve config in demo mode and play with ideas.
The only other way is to move the t sense to the cerbo. (Make sure its calibrated right). And use node red.
The t sense can still be used by DVCC connected to the cerbo.
Edited {sorry i went off on a tangent and then remembered your post said you have a MP2 GX.}
1 Like
Thank you for your reply.
I’ve had a good look using an Assistant using the ‘Programmable Relay’ assistant but I can’t see anywhere where one can set an cut in or cut out temperature. I’m doubting it’s possible 
Paul.
On an exact temperature, no. It is simple logic that side.
Thank you LX,
As I suspected. A bit bonkers really. Offer a temperature option but make it a boolean not analogue. Come on Victron, sort it out!.
Kind regards
Paul
Thats what node red does. So it is sorted.
Thank you LX. Yes Node Red does the job. Now if only we could control the AUX relay in the MP2 GX’s via Node Red that would be something!!
Thank you for your advice.
Is this video helpful? You wont be able to swith the heater load you will only be able to send a signal to a relay.
1 Like
Thank you for your reply but I have a Multiplus 2 GX with no Cerbo otherwise it would be easy.
Kind regards.
I thought it had a GX device built in. If you need help with node red let me know.
1 Like
Well, the built in “Cerbo” board of Multiplus II GX (and EasySolar II GX) does not have a relay (so neither relay settings). Also I/O settings only have “enable bluetooth sensors” entry (no analog inputs etc), although the device came with a sensor cable (for temp compensated charging).
Which would be a cute & cheap way to add such a relay to those devices? Something that could mimic the functions of a full blown Cerbo unit (temp, tank, generator, general…). Should it be some bluetooth device?
1 Like
Item G of course 
Item G is a useless relay and is controlled by an assistant or virtual switch. Item E is very useful. You can connect a cerbo GX to that I think, might be wrong I don’t know. Until they provided node red for multi-relays they are not even usable. Shelly devices are very good if you have wifi. Not sure what you have. If you need help let me know.
Thank you Owen. Looks like we’re on the same page. I’ll hassle Victron.
I’ll have a look at interfacing with Shelly as I have a few.
Check the current ratings on the relay and compare that to the current draw of the heating pads. The relays aren’t rated for much. On my battery warming system I chose to implement another set of relays to send power to the warming pads. In my case, the Cerbo GX relay is simply used to turn the relay on/off.
Unfortunately I don’t have the luxury of A external Cerbo GX otherwise it would be easy.
Kind regards
Paul
You don’t need a Cerbo GX. The point of my post was to warn you that your warming pads may be more current than the relay in the Multiplus can handle.