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

Status
Not open for further replies.
Copperclad

Copperclad

Member
Location
Merritt Island, FL USA
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?
 
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.
Click to expand...

Chris
 
Copperclad said:
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?
Click to expand...

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
 
Copperclad said:
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?
Click to expand...

Read ARTICLE 404.8(B) AND (C)
 
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
 
Copperclad said:
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?
Click to expand...

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
 
dicklaxt said:
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)
Click to expand...

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)
Click to expand...

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
 
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
 
Status
Not open for further replies.
Top