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t3z-gb avatar image
t3z-gb asked

Small BMS, Charge & Load disconnects for multiple devices.

Hello,

I’m seeking some advice or direction regarding load and charge disconnecting multiple devices from a Small BMS.

Curent setup,

160ah smart lithium, Small BMS, Orion Smart dc converter 2x 12-12-30, Smart mppt 75-15, victron smart inverter 2000va, smart batter protect 65.


In it’s current configuration, the SBP is connected to the vans load and controlled directly from the BMS’s load Disconnect

One of the onions is directly controlled by the BMS’s charge disconnect

My first question is how do I control the 2nd Orion, and the mppt in the event of under or over temperature? Can I simply daisy chains the charge disconnect from the BMS to all chargers? if not what’s best practice?

my second question is how do I disconnect the inverters load directly from the BMS? Or will this need an additional battery protect?

it seems like there are many scenarios to load and charge disconnect but not many outputs from the bms?


Thank you in advance


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1 Answer
Stefanie (Victron Energy Staff) avatar image
Stefanie (Victron Energy Staff) answered ·

@T3Z-GB

Not daisy chain them but wire them up to a distributor and from there with one wire into charge disconnect of your smallBMS.

For the MPPT you'll need a VE.Direct non inverting remote on/off cable that goes to the same distributor.

For the MultiPlus I think the 2-signal BMS assistant is required or alternatively a VE.Bus BMS. I suggest you search the forum for that one. I'm not experienced with that. A BatteryProtect with your Multi is no good idea because there's a risk of reverse current which will destroy the BatteryProtect.

Hope that helps.

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t3z-gb avatar image t3z-gb commented ·

@Stefanie

I don’t understand what you mean, everything is connected to a lynx Distributor, how would I turn both Orions and the mppt off with just one charge disconnect on the BMS.

Regarding the inverter I have just the Victron smart inverter 2000va not a multiplus.


Thanks.

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Stefanie (Victron Energy Staff) avatar image Stefanie (Victron Energy Staff) ♦♦ t3z-gb commented ·

@T3Z-GB

Ok with the Phoenix Smart Inverter. It has a remote on/off. This is even easier than with a Multi.

I didn't mean the Lynx distributor but a "splicing connector", for example a Wago 221-415 with 5 connections.

Then you would need to connect a wire from the charge disconnect of the smallBMS to the Wago connector and from there one wire to each of the two Orion Smart remote on/off terminal H pin and the VE.Direct non-inverting remote on/off cable from the SmartSolar to the remaining Wago connector.

Another wire from the Phoenix Smart inverter remote on/off H pin to the load disconnect terminal of your smallBMS.

Charge/load disconnect signal on the smallBMS is high in normal state. In case of low temperature, high cell voltage charge disconnect will become low and stop your chargers from charging. In case of low cell voltage load disconnect will become low and stop your inverter.

You can test this by simply disconnecting one of the BMS cables from the smallBMS, which should result in switching off all chargers and the inverter.

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t3z-gb avatar image t3z-gb Stefanie (Victron Energy Staff) ♦♦ commented ·
Okay fully understand now, thank you for all the help!!
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