Tony Miklos wrote:
On 1/10/2011 2:54 PM, Pete C. wrote:
Tony Miklos wrote:
On 1/10/2011 10:09 AM, Pete C. wrote:
wrote:
Good possibility? It is a definite FACT. With the 30 amp rating of the
conditioner,a 20 amp plug would be a requirement. Particularly on a 20
amp circuit.
Don't assume a 30A rating requires a 30A plug. That rating is the
maximum input current, and you can absolutely change the plug to a lower
rating if the load on the conditioner is less than full load. The
circuit protection is at the panel feeding the receptacle, so if that
receptacle is on a 15A or 20A circuit it is fine. If the load is too
high the breaker will trip.
Look at the pictures. Wouldn't you agree the breaker didn't trip?
We don't know what size breaker is on the circuit. We don't know what
the actual load amperage on the circuit is. It's entirely possible that
a bad connection caused overheating of the contact at well below even a
15A load.
I know that. Are you confirming what I wrote or disputing something?
Read the last sentance of the post up a couple levels.
It reads: If the load is too high the breaker will trip. So if the
breaker didn't trip, then maybe, just maybe someone is wrong when they
say "a 15 or 20 amp circuit is fine". Maybe if it had a 30 amp outlet
it would have made a better connection and never happened?
In the past I have changed 30A plugs on a UPS out for 20A plugs, since
the application had the UPS operating well below it's maximum ratings
(mostly sized for run time). This was perfectly safe since the 20A
receptacle was protected by the 20A circuit breaker, so if someone
improperly added loads to the UPS the breaker would simply trip.
Receptacle contact areas don't dramatically increase with current
rating. Yes, a 60A contact is notable larger than a 15A one, but there
isn't a lot of difference between a 15A and a 30A in many connector
styles (twistlock in particular).
The point here is that this is likely the result of a loose connection
in the plug, and nothing else.