mrsteve avatar image
mrsteve asked

Smart BMS 12/200 to Multiplus 12/2000 for camper system


I would like to get some feedback of the schematic i made for a small camper system.

The Smart BMS 12/200 looks like a nice "all in one" solution for alternator charging and BMS.

I used 80A fuses on the alternator side for a 60-70A charge..

The smaller DC loads and MPPT wil be connected to the System +, the Multiplus 12/2000 will be

on the battery side and disconnected in case of BMS alarm with the special cable:

I have read a lot of info here (not much info available for the Smart BMS 12/200) and seen webinars on alternator charging.. i think this setup should work fine.

A couple of questions:

1. If the "special" cable is connect from BMS to the remote port in Multiplus do i need to program

something extra in the Multiplus to make Charge or Discharge disconnect work?

2. Does the Smart BMS 12/200 work with all alternators? I have read Euro 6 with smart alternators

have a to low voltage to let the BMS charge full amp output say a 60-70A?

3. Some may say i need a (more expensive) BuckBoost DC/DC 50A, but i can't see the point in this if i can use the Smart BMS 12/200 as a "all in one" unit for this small installation?

Why would a BuckBoost be much better?

4. Could you guys check my drawing below for errors i may have made in this design.

Thanks much for your time and answers!


MultiPlus Quattro Inverter ChargerLithium BatteryBMSalternator
2 |3000

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out-to-sea avatar image out-to-sea commented ·
Were you able to figure out how to connect the load and charge disconnect cable from the Smart Bms 12/200 to the 12/2000?

I have been struggling mightily with this question.

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greg-2 avatar image greg-2 out-to-sea commented ·

You need the cable. I am assuming the 12/100 disconnect will work the same as the 12/200 as the connectors all look identical.

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Neo Nos avatar image Neo Nos commented ·
Why is the MultiPlus not connected to the System + Terminal on the BMS? Does your usage go beyond the AMP rating of the BMS? I am currently setting up a very similar system for my van and I was thinking to use the battery protect feature of the BMS I would put it on the System +. Any advice would be appreciated.
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Matthias Lange - DE avatar image Matthias Lange - DE ♦ Neo Nos commented ·
That BMS works similar to the BatteryProtect and because of that I would not recommend to connect a big inverter to it.

The manual shows it like that but I would not recommend it.

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Neo Nos avatar image Neo Nos Matthias Lange - DE ♦ commented ·

Thank you. Do you then recommend I get the "Cable for Smart BMS CL 12/100 to MultiPlus" or something? Do I need a battery protect sperate for Multiplus then or it is built in?

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Neo Nos avatar image Neo Nos Matthias Lange - DE ♦ commented ·
But then if I connect the MultiPlus to shore how will it charge the battery? Charge without respect to the BMS? I thought any current comming into the battery must go through Battery Management System.
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Matthias Lange - DE avatar image Matthias Lange - DE ♦ Neo Nos commented ·

The picture above shows you exactly how I would do it.

Charging/discharging from the MultiPlus is controlled via the special cable.

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Neo Nos avatar image Neo Nos Matthias Lange - DE ♦ commented ·

What would you do with all the other Orions and MPPT put them on System as long as below 200AMP? And thank you btw that gives me something to go off on. I think I am starting to understand I can utilize the Load Disconnect/Charge Disconnect to do the BMS job with other devices? This "Special Cable" I am guessing simply does that? Not sure what the dongle in the middle is for.

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