Multiplus ii 120Vx2 AC Input and Output

Hello!

I would like to know if I could feed two AC wires to AC In of the Multiplus ii or if it would cause any problems.

I have two Isolation Transformers (115V 32A 3600W), which will feed at max 65A. The Multiplus ii manual recommends 50A fuse/circuit breaker for AC In, but on Victron Connect App, it lets you limit the AC In up to 60A.

  1. Is the Multiplus ii AC In max 50A or 60A?

  2. Is it a good idea to have two AC wires feeding power to the Multiplus ii? Will it cause any issues to the device? Will these two wires interfere each other?

Quite new to the boating and marine electric systems. Would sincerely appreciate any comments, ideas, guidances…!

[For those who want more context]

I bought a used sailboat and upgrading its wirings. It had neither the isolation transformers nor galvanic isolators. It has two shorepower inlets, starboard powering AC main panels and power outlets and port powering A/C units.

What I want is to keep the existing wiring (startboard and port powering different part of the AC systems and not interfering each others) while being able to power either systems with an inverter.

I think the easiest and most simple solution is to feed two AC wires (30A each) to multiplus ii AC In and pass through 60A via AC Output 1 to power both AC main panels and A/C units. However, I’m just not too sure if the device could handle this or if there is any safety issues or unintended consequences.

Thank you!

Unless something has changed recently, the unit is only rated for 50a input which is likely due to the limitations of the transfer switch

Under typical conditions does the boat use the full 60a, or excess of 50a? It’s nice to always have full power available but if typical demand is under 50a you could downsize the input breakers to prevent damaging the multiplus

Now to bring up the biggest issue. I would highly recommend not trying to combine the 2 separate shore power inputs. This would in theory work fine if both shore power sources were fed from the same leg, but if they are out of phase you’ve just created a 240v dead short.

I would opt to use a separate multiplus for port/stbd

Thank you!! If it is not recommended to combine two ac cables together, I will get another inverter as you recommended. Makes sense…!