Cyberlights on 110V?

[QUOTE=tadawson;53810]
The units I am speaking of are UL/CE listed in enclosure - so what code problem again?


It must be a cord-connected transformer, listed as cord connected (and not a permanent install transformer with a connection cord added in the field), with properly rated connectors on both input and output. It also has to be properly rated (or appropriately de-rated) for the power factor and harmonic content of the fixture being connected. Ensure that it's setup for a US style grounding scheme, and not a 55v/55v center tapped configuration often used on jobsites in the UK and elsewhere.

If all of these conditions are met, then there is no problem.

[QUOTE=tadawson;53810]
And I don't know where 15 amp circuits came into the discussion, but certainly not from me. Note I suggested a 2400VA step-up, which pretty clearly implies a 20A breakered circuit . . . and I have seen damn few commercial facilities at which the utility power wasn't breakered at 20A . . . and pulling 1600 or so watts on a 20A circuit is not "this kind of load" it's more like "what it's rated for" . . .


The 15 amp circuit is my assumption, and here's why:
In most cases, if you have electrical service feeding an outlet, the current rating of the outlet must match or exceed the breaker's current rating. A 60-amp outlet can be fed by a 60 amp breaker, or a 50 amp breaker. That way you can never exceed the rating of the connector.

But, there's a special exception in the NEC for the standard residential/commercial 15 amp/120 volt outlet. You're allowed to feed a string of 15 amp outlets from a 20 amp breaker. The assumption is that you will plug in a lot of smaller loads that could add up to more than 15 amps, but that no single load will exceed the 15 amp rating of the connectors. The number of outlets allowed in the string, and the breaker requirements have changed substantially over time. The exact version of NEC in force at the time of the electrical install probably dictates.

Here's the problem: You can't tell from looking at a standard outlet if it's being fed by a 15 amp or a 20 amp breaker. Thus, to be safe you have to assume it's on a 15 amp circuit.

If a qualified person can determine it's a true 20 amp service, with no other loads connected, than you can draw 15 amps continuously and stay within the strictures of code (at that point the 15 rating of the standard US style power outlet would become the limiting factor since it's less than the 16 amps you can draw from an 80% de-rated 20-amp service)


One final detail:
If your outlet looks like this:
en.wikipedia.org/wiki/File:NEMA_5-15_Outlet_120V-15A.jpg
Then it's a 15 amp outlet.

If it looks like this:
en.wikipedia.org/wiki/File:Electrical_outlet_with_label.jpg
(with the T-shaped inlet on one side) Then it's a 20 amp outlet and should be fed by a 20 amp breaker (assuming someone hasn't changed the outlet since it was originally installed).


Beware that the 2400VA cord connected transformer we discussed earlier should have the 2nd style connector (with one blade at a right angle to the other). As such, it won't plug in to the 15-amp wall outlet.

[QUOTE=tadawson;53810]
The units I am speaking of are UL/CE listed in enclosure - so what code problem again?


It must be a cord-connected transformer, listed as cord connected (and not a permanent install transformer with a connection cord added in the field), with properly rated connectors on both input and output. It also has to be properly rated (or appropriately de-rated) for the power factor and harmonic content of the fixture being connected. Ensure that it's setup for a US style grounding scheme, and not a 55v/55v center tapped configuration often used on jobsites in the UK and elsewhere.

If all of these conditions are met, then there is no problem.

[QUOTE=tadawson;53810]
And I don't know where 15 amp circuits came into the discussion, but certainly not from me. Note I suggested a 2400VA step-up, which pretty clearly implies a 20A breakered circuit . . . and I have seen damn few commercial facilities at which the utility power wasn't breakered at 20A . . . and pulling 1600 or so watts on a 20A circuit is not "this kind of load" it's more like "what it's rated for" . . .


The 15 amp circuit is my assumption, and here's why:
In most cases, if you have electrical service feeding an outlet, the current rating of the outlet must match or exceed the breaker's current rating. A 60-amp outlet can be fed by a 60 amp breaker, or a 50 amp breaker. That way you can never exceed the rating of the connector.

But, there's a special exception in the NEC for the standard residential/commercial 15 amp/120 volt outlet. You're allowed to feed a string of 15 amp outlets from a 20 amp breaker. The assumption is that you will plug in a lot of smaller loads that could add up to more than 15 amps, but that no single load will exceed the 15 amp rating of the connectors. The number of outlets allowed in the string, and the breaker requirements have changed substantially over time. The exact version of NEC in force at the time of the electrical install probably dictates.

Here's the problem: You can't tell from looking at a standard outlet if it's being fed by a 15 amp or a 20 amp breaker. Thus, to be safe you have to assume it's on a 15 amp circuit.

If a qualified person can determine it's a true 20 amp service, with no other loads connected, than you can draw 15 amps continuously and stay within the strictures of code (at that point the 15 rating of the standard US style power outlet would become the limiting factor since it's less than the 16 amps you can draw from an 80% de-rated 20-amp service)


One final detail:
If your outlet looks like this:
en.wikipedia.org/wiki/File:NEMA_5-15_Outlet_120V-15A.jpg
Then it's a 15 amp outlet.

If it looks like this:
en.wikipedia.org/wiki/File:Electrical_outlet_with_label.jpg
(with the T-shaped inlet on one side) Then it's a 20 amp outlet and should be fed by a 20 amp breaker (assuming someone hasn't changed the outlet since it was originally installed).


Beware that the 2400VA cord connected transformer we discussed earlier should have the 2nd style connector (with one blade at a right angle to the other). As such, it won't plug in to the 15-amp wall outlet.