Using the Lynx BMS remote switch

Hi. I’ve just installed a 24V Victron NG lithium system on a new Narrowboat in the UK with 2* 24V 300Ah NG batteries.

There was some discussion with surveyor/system designer about using the ‘remote’ and Lynx contactor as the main isolator and if it was sufficient - rather than a main physical isolator switch. We decided it was better using the remote as so much more accessible and means leaving the neat Lynx system design as it is. And we have isolators after the Lynx Distributor for MultiPlus and DC loads.

An issue is that the SmartSolar doesn’t turn off when the Lynx BMS remote is used. The solar still powers up the boat/load side of the system. As far as I can see it’s all setup correctly. The SmartSolar is in ‘BMS controlled’ mode. Using the 150/85 VE.Can SmartSolar controller. And for the remote switch I’m using a 300A Blue Sea rotary switch so it’s an obvious isolator switch that can’t be accidently knocked off. Attached some pics.

Has anyone had this issue or have I missed something? Since the SmartSolar is controlled by BMS thought that maybe dialling voltages down to 0V may work but 16V is lowest setting. Also we would see the same thing fitting isolator switch between Power In and Lynx BMS.

I’m thinking of fitting a 2 circuit Blue Sea switch instead and having the 2nd circuit operating the SmartSolar remote but feel it’s a bodge? I assumed when the BMS was powered down with the remote it would disable SmartSolar too.

Hope that makes sense.

Thanks! Ed Shiers


I am not able to provide a solution but tag along because on my narrowboat I have a remote switch wired to the remote terminal of my Lynx NG BMS and have solar.

As the BMS contactor opens the GX device be powered down a short while later if this is powered from the Lynx BMS Aux supply. Is it this that prevents DVCC from stopping the solar and the MPPT goes into stand alone mode. If the Lynx BMS ATC relay is not controlling anything then you could use that for the remote port on the MPPT. This is not a choice for me as I have the WS500 feature in wire running through the ATC port. I can not check what happens in my case at the moment (a VE Direct MPPT) but will do so when I can.

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A follow up thought, if the inverter is on shore power and you operate the remote BMS on/off switch to turn the BMS off, does the inverter continue trying to operate without the battery connection, again a normal shutdown DVCC would stop the charging but in this case ??.

Hi Peter.

Thanks very much for the reply. I’ve been following your NG install with interest on the CWDF.

Yes the Ekrano GX is powered from the AUX port so possibly it’s that causing loss of communication. It’s not connected to the landline at the moment. Was also thinking maybe it takes a while for the voltage to drop off since there’s a big MultiPlus fitted - the boat’s along way from me so unable to check things out straight away.

I’ve installed a Wakespeed too but not using the ATC at the moment :grimacing: - using feature in to select a half power mode since I’ve had major problems with the WS not backing loads fast enough when throttling back to tickover in the past. The latest firmware seems fantastic though so have option to use the ATC. On a job last year with Lynx BMS + Mastervolt Alpha Pro used ATC in alternator mode and it turned the alternator completely off at 100% so I’m thinking the WS500 looses the ability to go to float using it?

Thanks, Ed

I found my solar would still power anything 12 volt connected to the Lynx distributor as it is downstream of the remote relay. I use this double pole switch to disconnect the solar and relay at the same time with good results. You can see it in the first picture here.

Are you running a Lynx BMS too? I think I will do the same for now and fit a dual circuit switch. I assumed with the SmartSolar controller setup in BMS controlled mode it would shut down when the Lynx-BMS was shut down, or if it lost communication such as unplugging VE.Can/VE.direct lead. When I get back to the boat I’ll have a play. Thanks, Ed

I do have a Lynx BMS. One pole of the switch is connected between the solar panels and the MPPT. The other side of the switch is connected to the Lynx BMS remote switch. That way it disconnects the battery and solar completely. I thought the solar would disconnect as well with the Lynx BMS but found I had 12 volts with the BMS off. Took me a minute to figure out where it was coming from. The MPPT was sending 12 volts to the Lynx distributor and from there to the 12 volt supply circuits. Now with the 2 pole switch everything is shut off.

Thanks. We’ve just done the same. :+1:

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