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s-rachui avatar image
s-rachui asked

High EMF with Multiplus

I have two Multiplus inverters installed in my motorhome. EMF readings at the inverters while these inverters are operatin are very high. The readings are reduced but still very high on the inside of the coach. I have tried to put EMF reducing cloth (purchased on Amazon) around the inverters and it doesn't make a difference. I wonder if these inverters are somehow installed incorrectly or have something enabled that is causing such large EMF readings. The readings are in the range of 150 mG (milliGauss). Any help appreciated.

Multiplus-II
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Alexandra avatar image Alexandra ♦ commented ·

@s_rachui

For interest, have you measured other devices in your motor home to compare readings to them?

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s-rachui avatar image s-rachui Alexandra ♦ commented ·
Yes, other devices in the coach are low. In the range of 0.5-1 mG. Also, if the coach is plugged into shore power then the inverters are working in passthrough and the EMF load for the inverters is also reduced to a very low level.
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Alexandra avatar image Alexandra ♦ s-rachui commented ·

Yeah the inverters on shore power aren't really working hard unless they are charging heavily.

I was curious what a microwave when on emitted.

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4 Answers
ludo avatar image
ludo answered ·

You are measuring magnetic fields, and the results are about what you'd expect using large transformers at high frequencies. If a cloth can help ? I wouldn't think so, it's probably more suited against electrical fields.


Try shielding with mu-metal, it's the best you can get for this purpose



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hjohnson avatar image
hjohnson answered ·

Are you trying to protect a magnetic compass, or an old school CRT monitor?


If not, don’t worry about it. Thankfully we humans are non magnetic, so magnetic fields have no effect on us. Anyone who claims otherwise is a charlatan trying to sell snake oil.

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rzwade avatar image rzwade commented ·
How do you protect a magnetic compass?

My inverter/charger is causing up to 30 degree variation.

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ludo avatar image
ludo answered ·

Some people believe in God, others in the dangers of magnetic fields.



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romen avatar image
romen answered ·

@s_rachui How far form the inverters are you getting the 150 mG readings? And what's the EMF value at 1 meter distance?

> The readings are reduced but still very high on the inside of the coach
So, is the inverter outside? Just trying to better understand your set up.

Also, what specific multiplus models are these two you have? Specifically, how many watts are they able to produce? And also, how many watts were they producing when you got those readings? Have you compared readings when producing a max output vs a min output (while working as an inverter)? The magnetic field produced should be directly proportional to the watts it is producing at a given time, but it would be great to verify that with your readings.

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