Circuit Breaker Ratings Table

Circuit breaker size 2.

Circuit breaker ratings table.

Table 41b2 of the wiring regulations gives the same maximum loop impedances. 4 not valid with chkd or. Series rating tables table 1. 3 where y 1 or 2.

Input ratings output amps dual element time delay fuse non time circuit breaker 3 motor circuit protector 4 140m motor starter with adjustable current range 5 6 nd hd khz c amps kva cont. Maximum loading of any circuit breaker is 80 of rating for non motor loads with exceptions as noted below. In this you will learn ratings of circuit breaker and making breaking capacity of circuit breaker a circuit breaker may be called upon to operate under all conditions however major duties are imposed on the circuit breaker when there is a fault on the system in which it is connected every electrical equipment will have rating mentioned on it to avoid the damage of it in the same way. Table a 208 volt ac input protection devices see page 7 for notes drive catalog number frame hp rating pwm freq.

The use of fuses and inverse time circuit breakers with nonstandard ampere ratings shall be permitted. Respective br anch devices shown directly below. Two pole breakers can be either slash or straight voltage rated whereas 3 pole breakers are all straight voltage rated. There are a few more things to consider in the calculation such as circuit breaker interrupting time and contact parting time remote and local short circuit current sources for.

While the determination of the closing and latching duty is fairly a straightforward process the calculation of the interrupting duty for medium and high voltage circuit breakers is a bit trickier. This exceeds the breaker s 277v line to ground voltage rating. 120 240 volts ac breaker breaker series ratings main devices shown in shaded area centered at top. 240 6 a fuses and fixed trip circuit breakers.

2 single pole version is restricted to 15 70 a. 1 where x 2 or 3. Table 2 load maximum circuit breaker size of current resistance loads heat stoves toasters water heater 125. Miniature circuit breakers which in the uk have been manufactured since 1965 to.

You must size conductors to the lowest temperature rating marking on the breaker. Additional standard ampere ratings for fuses shall be 1 3 6 10 and 601. Of the installation will determine which type of circuit breaker should be used. The standard ampere ratings for fuses and inverse time circuit breakers shall be considered as shown in table 240 6 a.