Inverter ZE Direct 12/500

DIY
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1

FIRST TIME USE.
emphasized textOne of my duplex 110 volt plug ins will not accept a two prong plug.
The large and small vertical slots that I attempted to insert could only go in after really being forced into the upper plug in. The lower of the two will not allow me to insert any male shaped plug in NO MATEER HOW MUCH FORCE I USE

3

Thanks, now that I know how it’s supposed to work I can get around the inconvenient safety measure.