Cam Lok Wiring

[imisspla07]

I have a technician who wants to use some 400A cam-loks they have for much lower loads (10A). The wiring to the 10A load is appropriately sized for that load and my concern is another tech will look at the 400A cam-lok and assume he can put it on another load up to 400A not knowing the wire is rated only for 10A. The tech argues that there's a breaker, but I told him the breaker is for short circuit and ground fault and the wire may melt before it trips. Is there anything in the code that mentions using wire sized for the receptacle so that I can show him if he wants to use the 400A cam-lok he will have to replace the wire too?

 

[zbang]

The tech argues that there's a breaker, but I told him the breaker is for short circuit and ground fault and the wire may melt before it trips.

How can that happen? The breaker's purpose is to protect the wire and devices (not for GF, unless it's a GFCI). By properly matching the overcurrent protection to the wire size, you protect everything. Besides, a 400a load will look like a dead short to a 15a breaker. Oh, and CamLoks are routinely wired to smaller breakers, it's not a issue.

That said, it's an awful waste to use $40 single-pole connectors for a 10a load.

 

[petersonra]

I don't have an issue with it. The branch circuit protection will protect the wiring regardless of the size of the connector. Seems like a waste of an expensive connector but I've seen people do the same thing for no real reason other than they stock 400 amp cam lock connectors and plugs and it's easier than having to add something else to the stockroom for spare parts.

 

[kwired]

I have a technician who wants to use some 400A cam-loks they have for much lower loads (10A). The wiring to the 10A load is appropriately sized for that load and my concern is another tech will look at the 400A cam-lok and assume he can put it on another load up to 400A not knowing the wire is rated only for 10A. The tech argues that there's a breaker, but I told him the breaker is for short circuit and ground fault and the wire may melt before it trips. Is there anything in the code that mentions using wire sized for the receptacle so that I can show him if he wants to use the 400A cam-lok he will have to replace the wire too?

Thermal magnetic breakers provide overload as well as short circuit and ground fault protection.

For some applications like motors you size them higher then usual to allow for motor starting current, but you must also provide additional overload protection in those applications. Still if you connected a 400 amp load to a 10 amp breaker, as mentioned before it would look about like a short circuit to the breaker and it would respond in similar fashion as it does to short circuits.

The breakers first main purpose is to protect the conductors connected to it, if sized to protect those conductors it should trip before they even come close to melting.