Switch Amperage Capacity
- Thread starter dale57
- Start date
- Status
bphgravity
Senior Member
- Location
- Florida
Re: Switch Amperage Capacity
A-C general use snap switches are tested for the control of resistive, inductive (including electric discharge lamp) and tungsten-filament lamp loads at 120 V up to the full current rating of the switch, and for motor loads up to 80% of the amp rating of the switch but not exceeding 2 hp.
A-C general use snap switches are tested for the control of resistive, inductive (including electric discharge lamp) and tungsten-filament lamp loads at 120 V up to the full current rating of the switch, and for motor loads up to 80% of the amp rating of the switch but not exceeding 2 hp.
jeff43222
Senior Member
- Location
- Minneapolis, Minnesota
Re: Switch Amperage Capacity
I suspect that since switches are generally used for lights, and since lights are considered continuous use loads, they derated the ampacity of the switch since you really aren't supposed to have more than 80% of 20A running through the switch.
-Jeff
I suspect that since switches are generally used for lights, and since lights are considered continuous use loads, they derated the ampacity of the switch since you really aren't supposed to have more than 80% of 20A running through the switch.
-Jeff
bphgravity
Senior Member
- Location
- Florida
Re: Switch Amperage Capacity
They didn't derate the switch. It is good for 100% of its rating, the 80% is for motor switching not general lighting. Not all lighting is considered continuous, you would have to make that determination at a per installation basis.
jimwalker
Senior Member
- Location
- TAMPA FLORIDA
Re: Switch Amperage Capacity
???? will they be on more than 3 hours ?
???? will they be on more than 3 hours ?
bphgravity
Senior Member
- Location
- Florida
Re: Switch Amperage Capacity
At 2200 watts, I don't think the lights can be plugged into one receptacle. It violates the 80% rating per 210.21(B)(2) and would violate 210.23(A)(1) if only one 20A circuit.
In this case, I would split the lights into 2 equal loads and feed with 2 15A or 20A branch circuits.
Also, do cord-and-plug connected loads get counted into continuous loading?
[ June 16, 2004, 08:53 PM: Message edited by: bphgravity ]
At 2200 watts, I don't think the lights can be plugged into one receptacle. It violates the 80% rating per 210.21(B)(2) and would violate 210.23(A)(1) if only one 20A circuit.
In this case, I would split the lights into 2 equal loads and feed with 2 15A or 20A branch circuits.
Also, do cord-and-plug connected loads get counted into continuous loading?
[ June 16, 2004, 08:53 PM: Message edited by: bphgravity ]
- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
Re: Switch Amperage Capacity
Good question! I am inclined to think not. The load considerations for cord-and-plug equipment are taken into account with the receptacle load. Someone might say that any given receptacle load might be on for more than 3 hours, and they might site a reading lamp as an example. I would counter by suggesting that the 180 VA per receptacle is based on a ?real? load of 144 VA, and that 25% has already been added to that number, thus bringing the total to 180. In any event, I see nothing in the code that would lead me to add 25% to receptacle loads.
- Status