[Amps] NEC-think.

[John Popelish]

R.Measures wrote:

> Without a ground/bond wire wouldn't connecting the Neutral wire to the 
> metal enclosure hold the enclosure to a safe potential until the 
> breaker trips?

The neutral carries load current, so it may have some voltage drop at 
the appliance end, compared to the end at the power panel.  And if it 
ever goes high resistance, then the moment any load is connected to 
it, it has full line voltage on it.  So a single failure (open 
neutral) would produce a shock hazard if the case were attached to it, 
the moment the appliance was turned on (a moment someone is likely to 
be touching the case, also).

The safety ground never carries current under normal conditions, so it 
take two failures (hot faulted to metal case and open ground 
conductor) to produce an unsafe condition.