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Connecting electrodacus SBMS0 to multiplus 12/3000/120

kylepaulin

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Dec 23, 2020
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First post, hopefully it’s a straightforward question!

I’m connecting my SBMS0 to my multiplus to switch the inverter off for LVD using EXTIO3 and the charger off for HVD using EXTIO4.

In my multiplus manual these are the explanations of the remote on/off - “Connections for remote switch: Short left and middle terminal to switch the
Multi “on”, Short right and middle terminal to switch the Multi to “charger only”. “

Where do the positive and negative from EXTIO3 go? Where the positive and negative from EXTIO4 go?

Sorry if this has been asked before, I did try searching the forum but couldn’t find an answer.

Many thanks!
 
Welcome to the forum.

See the diagram and picture here:


1608838788204.png

Terminal "H" is the blue block with the black wire looped from position 1 to 2 - this enables the inverter/charger. To disable the inverter/charger, all three pins are open. To enable charger only, short positions 2 and 3.

Summary:
Pins 1-2 shorted, inverter/charger enabled
Pins 2-3 shorted, inverter disabled, charger enabled
Pins open: inverter and charger disabled

Unfortunately, I can't assist you on the specifics of the Electrodacus output. It does not seem to be designed with your desired function in mind but rather for solar charging only. Ideally, you would want LVD to open pins 1-2 but close pins 2-3 to allow charging. At HVD, you want to disable charging, but you still want to be able to discharge. The Multiplus can't function in that manner. There MIGHT be a way to accomplish both of these functions via a GX device where it receives the EXTIO 3 and 4 signals and controls the inverter/charger functions independently via the data cable.
 
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Thanks for your replies. I can find Tsense on the multiplus but where would I find the Aux i/O?
 
I have an older multiplus that doesn’t have Aux i/O ports.

is there any other way I still use this multiplus with the SBMS0? I will look into the suggestion of using a GX device.
 
I believe I also have a older Quattro with no AUX IO ports. Note the line the PDF linked to above "The Multi or Quattro needs to be of a recent type that has auxiliary inputs."
Talking to Dacian, he confirms I need SSRs to switch off the ACIn1 and ACIn2 on a signal from EXT IO4. Thats what I plan to do.
But I'm a bit confused about "Terminal H" in the above picture vrs AUXIO. First there are 2 AUX IO pairs ? which one should be used ?
The options for Terminal H look incompatible with SBMS0 EXT3 and EXT4 options.
 
I too have just bought an older Multiplus so will be all over this issue when I get some time v soon. Basically from my electrical background the issue is that the blue term block 'H' has a common pin (pin 2 / centre pin) which carries voltage and pins 1 & 3 are the switched return signals that come back from 'volt free' contacts in relative control devices. The BMS module works on the same principle but only in binary form i/o (on/off) so you cannot mix the two. However, it is possible to use a SSR to interface the two outputs and end with the same result.
 
This is a 12v unit, I'm just looking for a 24v same same....
 

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I looking to wire up my Multiplus 24/3000 to a electrodacus SMBS0 and am curious if anyone had good luck getting things wired up and programmed? I came across another post in my search here that made it sound even easier than this thread.

Can anyone shed light on this?
 
It's really straight forward. Look at @snooblers post above. You need to program the 2 wire BMS assistant either over VRM if you have a GX device, or with an MK3 to USB adapter. Then you wire up the the extio port on the SBMS to the Aux1 input and set the type you defined in the assistant. Then wire up a different extio port to the Aux2 (or t-sense if you don't have an Aux2).

Then in the SBMS0 you can define whatever extio you defined for battery full as the type 1 and when battery is empty as type 2.

type 1 is for chargers and the EXT IOx will be open circuit if any cell exceeds the upper set limit as an example 3.55V for LiFePO4
type 2 is what you will use for an inverter and EXT IOx will be open circuit if any cell is below low limit example 2.8V for LiFePO4

Hope this helps!

1633126481630.png
 
Old thread hopefully someone sees this - do you remove the jumper (item H) on the multiplus if you are using the two signal bms function for eletrodacus?
 
No because that will disconnect both the charger and inverter. See my above post for how to set it up correctly.
 
Ok thanks I am comfortable I have the aux 1 and 2 set up correctly and once I get access to Victron configure I can set up the assistance correctly for Multiplus
What I wanted to explicitly know is I just leave the jumpers as received and I assume that is a yes
Pins 1-2 shorted, inverter/charger enabled
Pins 2-3 shorted, inverter disabled, charger enabled
Pins open: inverter and charger disabled

As it seems there is a software overide for the on / off/ charger only mechanical switch I was confused that this might be the same with the H port

Thanks for the response - now onto find a laptop i can install the Victronconfigurator on - doing via VRM remote and Cerbo looks way too involved
 
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