I currently have a Multiplus 24v/3000/70amp. I understand a multipus II would be optimal for my situation, but I don’t have that. My Gen has L1 and L2 on split phase. The multiplus only has L1 for AC input. Can or should I go from my Gen through an autotransformer to step the current to single ph…

You have a 120v MultiPlus, do not connect 240v to it. [120] Editing to add: also worth noting that it does not have L1 and L2 outputs (reading back to your original post). It has AC-Out 1 and AC-Out 2, which is a different thing. Please study the user and installation manuals for the unit prior …

If the gen has no other loads, and IF the center is grounded, then isolate the ground, carry out in insulation test on the winding. If good, then move the earth to L2, treat this as the ‘Neutral’ connection, L1 as the ‘Live’ and ignore the generator’s center tap (old N connection). If there are oth…

So if there is no Earth connection on the winding, I can treat the N input on the multiplus as if it were L2? And should Gen N be connected to Gen Ground but not fed into N on the Autotransformer?

[image] sedrictrev: And should Gen N be connected to Gen Ground No. IF there is no earth on the gen winding, and you connect L2 to the N terminal on the Multiplus, then the Gen ‘N’ connection should not be used. Gen Ground ‘Chassis’ connection should be connected to the MP earth / chassis con…

So I am finally getting back to this project. Here is a diagram of how I am wiring it. I only hooked up wires as far as the Multiplus and plugged into shore power just to test and see if all was working well. As soon as I flip the breaker on between the auto transfer switch and the Multiplus it tri…

In the “off position the Multi will not connect the N and G terminals to each other. When the inverter is in invert mode, N and G are connected internally, for the AC out ports only. As the inverter switches into charger mode, these are briefly connected on the AC in, as the AC in connects before th…

The surge protector is technically on the output of the shore power, to protect the complete RV from any surge. The GEN does not go through the surge protector if you look at my drawing. I should have been more clear before, I am not running my gen right now, only plugged into shore power. When I …

[image] sedrictrev: When I ohm out on the MP, there is some continuity between L1 and N. There will be some load on this circuit, due to the AC in measuring setup. This should be quite a high resistance. If you are having input problems, then it may be worth considering an input isolating tra…

I should have been more clear. With all wires disconnected from the MP there is continuity between L1 and N. I guess I want to stick with 240V input if I can, both 50A shore power and my gen provide 240V. I wonder some days if just breaking down and getting a MP2 is what will eventually happen. I …

is your multiplus a 120 or 240V model?

Split phase 240V Generator with a Multiplus 24V/3000/70amp

Q&A and troubleshooting

sedrictrev (Sedric) 21 September 2025 01:39 12

The MP Voltage is rated in DC, not AC to my knowledge. Unless there is more to this that I don’t know. Not sure how to tell what one is rated for in relation to AC.

Here is a pic of it. It is a Multiplus 1, not a 2

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Split phase 240V Generator with a Multiplus 24V/3000/70amp

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