Breaker Sizing for Low Voltage
- Thread starter eanton22
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LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
There are instances where an OCPD may exceed the conductor's 310.16 ampacity.
How low a voltage are we discussing?
How low a voltage are we discussing?
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
Think about what you said there.
The PURPOSE of the breaker is to protect THE WIRE. So if you have a 20A breaker with wire connected to it that is rated for only 10A, what good s the breaker? By the time it trips, the wire is already carrying twice the current it is rated for and may already be in fire. Conversely if you have wire rated for 20A and a circuit breaker that trips at 10A, the breaker may trip sooner than it needed to, but what harm was done? Other than inconvenience, none.
The PURPOSE of the breaker is to protect THE WIRE. So if you have a 20A breaker with wire connected to it that is rated for only 10A, what good s the breaker? By the time it trips, the wire is already carrying twice the current it is rated for and may already be in fire. Conversely if you have wire rated for 20A and a circuit breaker that trips at 10A, the breaker may trip sooner than it needed to, but what harm was done? Other than inconvenience, none.
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