Todd Wackford avatar image
Todd Wackford asked

Is this the correct wiring to switch Multiplus 120|3000 L2 between Shore and Inverter?

I have an RV with 50 amp service (2 - 50 amp legs) and I am trying to have onc side of the coaches breaker (L2) hot from either shore/generator or the AC Out L2 from the Victron Multiplus Inverter. Normally the inverter will provide power to L2 when hooked to shore/generator, but only around 27 amps. I would like to get the full 50 amps on shore/generator and use the inverter's L2 (using assistant) only when on battery/inverting. So here is how I am thinking I need to wire it up. See picture.

Notice I only have the L2 hot going through the selector switch. I don't think I need to isolate the neutrals, or do I?

Thank you in advance for your advice.

MultiPlus Quattro Inverter Charger
2 |3000

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2 Answers
Todd Wackford avatar image
Todd Wackford answered ·

Well, while waiting for an answer I tried it and it all works. I am not able to see L2 voltage, current or power in the GX though. Am I suppose to be able to see it? I do like how it boosts whether the load is on L1 or L2 out of the multiplus. Both air conditioners, fridge and electric water heater capping at 10A in for a test :-)

I must say, "Well done Victron". The pieces all make for a well done system. And with the open-ness of the Venus GX, I'll be able to geek-out on the things that can be done for automation.

1 comment
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With two AC inputs, you may have been better served with a Quattro, which is designed for this and would show voltage on both.

It has a programmable internal transfer switch for both AC inputs, instead of your manual one now. Regardless, Congratulations on the installation.

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Paul B avatar image
Paul B answered ·

Two things I see that should be looked at, also you will not see the voltage and current from L2 in the CCGX at all.

if you want to do that you would need to change out the L1 and have the selector switch change l1 or L2 to the Ac1 in

the way you are doing is is to have the L2 switch control the heavey loads and if L1 fails then the inverter only runs the loads connected to ac1 out

1. there is NO breaker in the L2 active line (you have a 1 x 50amp breaker in the L1 active

2. the neutral from AC1 out and AC2 out should NOT connect to the AC1 in neutral.

To overcome this the switching selector should be double pole switching both active and neutral

I have rejigged your drawing

Link details

Note from victron copied and pasted

Johannes Boonstra (Victron Energy Staff) · Oct 24 at 2:29 PM , The reason for this is indeed that the Quattro (and also Multi models) measure the current internally so bypassing the unit is not possible.

Johannes Boonstra (Victron Energy Staff) ♦♦ · Nov 08 2018 at 2:39 PM By wiring it as in the diagram the switching of the feedback relais is single pole and this should be double pole (according to regulations and safety of course). So have a common Neutral for input /output is NOT supported.

1559978096129.png (227.2 KiB)
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