MP2 Should the input and output voltage be closer?

Should the input and output voltage be set closer?. Currently the grid averages 238v and the output is default 230v seen during load shedding.
Not my system but assisting someone that has been let down by her installer.

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Output voltage will be equal to the Input voltage while the Grid is available because the Inverter “Sync” with the grid. During this time the output will follow the input voltage and you will see that if the grid voltage fluctuate, the output Voltage will also fluctuate. During Load Shedding, there is no “Reference” Voltage to “Sync” to and the inverter output will be at a steady 230V.

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Hi Mako, you might be mis-reading the graph?

The blue is the output voltage with the scale on the left and the yellow is the output current with the scale on the right.

You’d need to view the AC Input Voltage & Current graph with the AC Output Voltage & Current graph and then compare the two blues.

Nevermind, I see what you mean.

Yes I understand what I’m seeing. Just wondering if the output (off grid) should be set (can it be set?) to 238v for a smoother changeover. Does it matter? I think I read somewhere that it does matter but can’t find the post.

Yes, you can adjust the output voltage, but I would not bother. When the grid fails, there is always a momentary drop-out in average voltage (because it takes up to 20ms to switch) anyway. The changeover is never going to be a smooth thing, it’s always going to jump a little.

Changing back to the grid might be a different matter. If you put them closer together, there will be less of a jump, but this is already within 3% so again, I probably wouldn’t bother.

Setting the default MP2 output voltage (i.e. only used during loadshedding) to try and match the “normal” grid voltage is not always that useful, since the grid voltage can vary quite significantly between low-use and peak-use times.

I have a 3kW MP2, so I set the voltage to 220V (rather than the typical 230V - 235V) so that I can still use some higher-power appliances with resistive loads. The only downside is that you may notice a slight flicker of lights when Loadshedding starts.

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Thanks all, I will delete that query from my cluttered brain and make space for something else :wink:

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OK, great. I wasn’t the only one.