Hello,
We want to install a new emergency off switch that has two NC switches inside. It works fine with our gear:
Smart Lynx BMS, 3x Multiplus II and RS 450 MPPT.
We are now wondering if there is a way to connect all this gear by wire (not programmed) for emergency off on this one switch?
We can’t use the aux relays, as we want this emergency to only work by wire and when emergency button is pushed.
Is it as simple as connecting them in parallell? I assume not.
Many thanks
Probably have the inverter one on its own for the safety switch assistant. It only needs to be wired to the master.
You can wire a few mppts into one switch. (I have done this) It is of course good to test as connection resistance matters. I have not used the lynx bms in this way.
The other way to do it is switch to h/L. So its one wire to each but you will have a wire with voltage.
Thanks for reply.
I have so far found no info in the manuals that tells me if we could do it and if the terminals are all the same across all Victron gear like MPPT, Multiplus and Lynx BMS. It seems likely that they should be designed the same maybe, and in that case it might not be complicated but do not want to risk causing some new issues.
Not all mppts have the remote on off, so you will have to check your model. But there are section in the manuals about it for the ones that do have them. What models are in the design?
The lynx bms also has something. Are you using the victron batteries?
The inverter uses the safety switch assistant as i mentioned. On some models there is another switch on the board internally but that one is fussier. The safety switch assistant was designed for emergency shut downs.
RS 450/200, 3x Multiplus II and Lynx Smart BMS. They all have remote terminals that in theory works the same.
Not using Victron batteries.
So why the bms or do you mean the shunt?
If you use the remote you have to wire all three unless you want to see the errors like unexpected device shutdown and device missing, etc errors. For your use case since it is for an emergency stop, use the safety assistant and you only need to wire it to one unit not all three.
That way consequent restarts are easier and less prone to problems.
I am using The Smart Lynx BMS with a loop cable, for the precharge, contactor and for local and remote cutoff of batteries, apart from the shunt.
Thanks for the tip on the safety switch assistant. The only thing I don’t like about it is that it only powers off the output. Will have to research that.
This is for serious emergency-type incidents so I want a complete shutdown.
So its stops charge/discharge as well. No power moves into or out of the battery when the switch is pressed. (No load = no power flow).
You van always go with the other route, will be keen on if it was seamless or not. For single phase it could be ok, but three phase things work a little differently.
Still potentially the AC power on the input of the Multiplus. But your suggestions make sense, thanks.
If it is that important then you could add a contactor on the input signalled by the same switch.
Good suggestion. Will have look at that, and also to just shut all the Multipluses down. Will test it when the time comes.
Is there a risk in paralleling all Victron units remote terminal is probably my main question if anyone has dome it.
I know one of one installer who did and had some of the issues i mentioned above. And random problems ensued. Eventually removed the remote switch.
I will add though that they are not the most particular workman, so it could have been that.
Interesting link where it says “The text in the assistant is imprecise in this case, the safety switch also disables charging.”
This is what I based my comment above on, that it will not stop the AC charge coming in, so will definitely try this, thanks!
I have used it. There is a video in th link above showing what happens when the e srop is pushed with the safety assistant and the the rmeote wire to the mppt is there as well.
If we have the ESS assistant installed for a LiFePo battery bank, will there be a conflict? D you know?
I am new to ESS and do not think the ESS assistant switches the multipluses but the link you gave also says:
“This assistant cannot be combined (yet) with other assistants which also control the switch state of the device. At the moment of writing the conflict arises only with any assistant configured to handle a BMS (battery monitor system] for Li-lon”
Is the bms can connected to the GX? If it is then there is no problem there, there can be if you have the two wire one with the assistant.
ESS is not using switching so that’s not an issue.
Understood. Yes the BMS is connected to the GX and we are not using the two wire assistant so far. Will test this asap.
Thanks again!