Hello,
please excuse me if this question seems too obvious. I am in an argument with a colleague over how we connect wires inside of some equipment we manufacture. In particular, we manufacture electrical measurement products housed in metal enclosures, for lab use, which typically sit on top of a lab bench. This product is about 30 lbs, steel box roughly 1' x 1' x 2'. The product has a standard fused/switched power inlet which accepts a linecord with an IEC320-C14 female on it. This line cord is intended to be plugged into a standard 120V/60Hz wall outlet (Line, Neutral, GND) in the USA. Our product consumes at most 300W.
It looks like one colleague may believe it is OK to connect neutral and GND together within our product. I'm saying "no way". My justification for saying no way?
1) General knowledge that the PEG conductor in the line cord is normally not supposed to carry any current. Connecting neutral to GND within our box will result in the PEG in the line cord carrying roughly half the load current. This is just one of several bad things which would happen.
2) This section of IEC 61010:
4.3.2.5 MAINS supply
...d) Equipment for single-phase a.c. supply shall be connected both with normal and reverse polarity.
W/regards to IEC 61010 4.3.2.5 (d), my argument goes as follows:
IF we connect PEG to neutral within our product, THEN a line-to-neutral short will result if our equipment is connected as specified in IEC 61010 4.3.2.5 (d).
But...I would like a stronger argument, perhaps a reference to NFPA 70, NEC, etc? If someone can mention a document and specific location within the document, I can get that document and look it up myself. I just want something very short and sweet.
Many Thanks, rtec
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