inline fuses to accomplish box fill

GSXR600

Senior Member
Hi,
I was asked to install a door jam switch which has a very small box. The circuit is 20 amps so we are using 12 AWG. The box will not allow for a 12/2 and the device per box fill. Does anyone know of a better way to do this. I was thinking put 15A inline fuses on that portion of the circuit and run a dead end 14/2 to the door jam switch. What are your thoughts?
 

cadpoint

Senior Member
Location
Durham, NC
I'll assume that this is a single gang box in the wall?

They make a 4 Sq. box that is cut out in the back to recieve/connect to a single gang box.

I've only ever installed 4 Sq. boxes for door controls/contacts. While the 4 Sq. was probably excessive since
it just turns into a raceway.

Most of the time something else is controlling the contactor.

I can't comment on a fuse in-line at that this point of intsall, because I've never seen
it installed that way. My thought is how would anyone that a fuse is in this set-up anyways?
 

John120/240

Senior Member
Location
Olathe, Kansas
cadpoint, this is a door jamb switch as seen here...use only one two wire as a switch loop. 14 AWG or 12 AWG. Our inspectors around here understand the application and have always overlooked any box fill violation.
 

Attachments

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Maybe this is an opportunity to use fixture wire, treating the wiring from a nearby larger box to the switch and back essentially as a fixture whip?
Are there other loads that require the circuit to be 20A instead of 15A?

Tapatalk!
 

ActionDave

Moderator
Staff member
Location
Durango, CO, 10 h 20 min without traffic from wing
Occupation
wire pulling grunt
Hi,
I was asked to install a door jam switch which has a very small box. The circuit is 20 amps so we are using 12 AWG. The box will not allow for a 12/2 and the device per box fill. Does anyone know of a better way to do this. I was thinking put 15A inline fuses on that portion of the circuit and run a dead end 14/2 to the door jam switch. What are your thoughts?
I'm thinkn' what Gold is thinkn'. Change the breaker and use 14AWG.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
We use a 15 amp circuit and 14-2 AC cable for these. The box has about 5-6 cu. in. of space.
 

curt swartz

Electrical Contractor - San Jose, CA
Location
San Jose, CA
Occupation
Electrical Contractor
I know its a code violation but I would not loose any sleep using 14-2 for these dead end switch legs. The jamb switches are only rated for a few amps so it would be impossible for the switch loop to ever get overloaded. Of course if the inspector sees this he may not allow it.

I really try to avoid this style of switch. The amount of time it takes to coordinate the installation with the finish carpenters can be a real pain. The doors are not installed during the rough wiring and when we come back to finish the doors are installed and painted. The owner and GC are not happy when they have to call the finish carpenters back to hack into the door, re-paint, etc.

I try to use low voltage contacts with a remote relay or motion sensors for this type of switching.
 

PetrosA

Senior Member
According to the instruction for the Leviton 1865 door jamb switch, the terminal screws accept up to 10 AWG wires. This would suggest that the switch assembly is listed for use with #10 conductors regardless of box fill calcs per the NEC. The switch itself is only rated for 3A @ 120V. I wouldn't sweat it.
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
I guess it would matter whether the switch is sold separately and could be installed in a general purpose box (fill would apply) or is sold as a combination of switch and box.
In that case the NEC would not have much to say about the fill of the "terminal housing" of the assembly.

Tapatalk!
 
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