tap rule

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GSXR600

Senior Member
under the tap rule what does it mean when they say terminate in a single circuit breaker or set of fuses. does that mean that you must use a ECBor a fused disconnect?
 
G

GSXR600

Senior Member
yeah but it say nothing about a MLO panel board it state it must terminate in a single circuit breaker. I have never seen a double circuit breaker. Why do they say a single circuit breaker????
 
S

shepelec

Senior Member
Location
Palmer, MA
They do not want the tap to terminate in 2 or 3 single pole breakers. So they say " a single breaker". It could be a 2 or 3 pole breaker such as a main breaker panel or a fused disconnect.
 
J

jim dungar

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GSXR600 said:
yeah but it say nothing about a MLO panel board it state it must terminate in a single circuit breaker. I have never seen a double circuit breaker. Why do they say a single circuit breaker????
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To prevent a wireway with multiple connections (if the wires are the same size they are not taps).
 
charlie b

charlie b

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Lockport, IL
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Generally, we have to protect each conductor against overcurrent, and we have to do it at the point at which the conductor gets its voltage supply. The tap rules give us the ability to protect a conductor at the other end, the load end. That represents a degree of risk, since a fault in the middle of the run would not have any protection. To reduce the risk, in addition to providing physical protection for the conductor, the rules require that the overcurrent protection consist of a single overcurrent device. It can be the main breaker in a breaker panel, or the main fuse in a fuse panel, or an enclosed breaker, or a fused disconnect. But it can only be one such device. In other words, you don't get to use the "six handle rule" in a tap rule situation.
 
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