Circuit Breaker Ratings Table

Circuit breaker size 2.

Circuit breaker ratings table.

Table 2 load maximum circuit breaker size of current resistance loads heat stoves toasters water heater 125. Table a 208 volt ac input protection devices see page 7 for notes drive catalog number frame hp rating pwm freq. Series rating tables table 1. Of the installation will determine which type of circuit breaker should be used.

Breaker cannot be larger than ampacity of wire except for motors and a few other loads. This exceeds the breaker s 277v line to ground voltage rating. Table 41b2 of the wiring regulations gives the same maximum loop impedances. Miniature circuit breakers which in the uk have been manufactured since 1965 to.

Maximum loading of any circuit breaker is 80 of rating for non motor loads with exceptions as noted below. Additional standard ampere ratings for fuses shall be 1 3 6 10 and 601. The use of fuses and inverse time circuit breakers with nonstandard ampere ratings shall be permitted. 240 6 a fuses and fixed trip circuit breakers.

3 where y 1 or 2. Respective br anch devices shown directly below. 4 not valid with chkd or. Two pole breakers can be either slash or straight voltage rated whereas 3 pole breakers are all straight voltage rated.

You must size conductors to the lowest temperature rating marking on the breaker. For 240 volts ac branch bre akers see table 2. N bs en 60898 the m category ratings for short circuit capacities disappear. 120 240 volts ac breaker breaker series ratings main devices shown in shaded area centered at top.

The standard ampere ratings for fuses and inverse time circuit breakers shall be considered as shown in table 240 6 a. 2 single pole version is restricted to 15 70 a. 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. 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.