2pole 30a. switch for 480 v install?!

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Ok, my boss is really irritating me......
Hes telling me that a 2 pole 30 amp switch rated for 277 max voltage is ok to control a bank of 480 volt 1000w metal halide floods!?
The amperage may be ok, but to me a 277 volt rated switch does not mean 277 on each pole?
Am I wrong?
 

raider1

Senior Member
Staff member
Location
Logan, Utah
A 120/277 volt 2 pole switch could not be used for a 480 volt circuit. Check out 404.8(C)

(C) Multipole Snap Switches. A multipole, general-use
snap switch shall not be permitted to be fed from more than
a single circuit unless it is listed and marked as a twocircuit
or three-circuit switch, or unless its voltage rating is
not less than the nominal line-to-line voltage of the system
supplying the circuits.

Chris
 

raider1

Senior Member
Staff member
Location
Logan, Utah
I was also looking at 404.14b(2)
would a 1000 w metal halide flood not be considered and "inductive" load?
not to exceed 50% of the switch ampere rating?

That still doesn't resolve the problem that a 120/277 volt switch is not rated to control a 480 volt line to line load.

Chris
 

LEO2854

Esteemed Member
Location
Ma
Ok, my boss is really irritating me......
Hes telling me that a 2 pole 30 amp switch rated for 277 max voltage is ok to control a bank of 480 volt 1000w metal halide floods!?
The amperage may be ok, but to me a 277 volt rated switch does not mean 277 on each pole?
Am I wrong?

Read ARTICLE 404.8(B) AND (C)
 

dicklaxt

Senior Member
So whats the answer?????

The first scenario I contend that if the ballast has an input potential of 480v then the switch must be 2-pole and be rated for 480v or greater.

See 404.15(A)

The second scenario would be if the distribution was 3 phase 4 wire- 480v/277v and the ballast input voltage was 277v then a 2- pole 277v or greater rated switch would be okay.

Once again see 404.15(A)

Now don't go fight with your boss this is just my opinion......:)

dick
 

dicklaxt

Senior Member
Ok, my boss is really irritating me......
Hes telling me that a 2 pole 30 amp switch rated for 277 max voltage is ok to control a bank of 480 volt 1000w metal halide floods!?
The amperage may be ok, but to me a 277 volt rated switch does not mean 277 on each pole?
Am I wrong?

I don't see that there is a firm answer yet,can someone hammer this out?See my comment and tell me if my thinking is right or wrong.

dick
 

raider1

Senior Member
Staff member
Location
Logan, Utah
So whats the answer?????

The first scenario I contend that if the ballast has an input potential of 480v then the switch must be 2-pole and be rated for 480v or greater.

See 404.15(A)

I would agree.

The second scenario would be if the distribution was 3 phase 4 wire- 480v/277v and the ballast input voltage was 277v then a 2- pole 277v or greater rated switch would be okay.

Once again see 404.15(A)

I disagree, if you put 2 277 volt circuits from different phases on the switch then you have a 480 volt potential and the switch would need to be rated for 480 volts. The rating of the 2 pole switch has to do with the maximum voltage line to line voltage on the contacts not the rating of the loads.

Chris
 

dicklaxt

Senior Member
I don't read the OP to say that there are 2-277v circuits.Now that you have said that I wonder what the real facts are.

dick
 
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