IEEE Std C37.13a:2012 pdf free download

IEEE Std C37.13a:2012 pdf free download.IEEE Standard for Low-Voltage AC Power Circuit Breakers Used in Enclosures Amendment 1 : Increase of Voltagesto 10oo V AC and Below.
a) Stationary or drawout type of two-. threc-. or four-pole construction with one or more rated
maximum voltages of 1058 V. 730 V. 635 V 600 V for units incorporating fuses). 508 V. and
254 V for application on systems having nominal voltages of 1000 V. 690 V. 600 V. 480 V. and
240 V respectively.
5. Ratings
5.2 Rated maximum voltage
Change 5.2 asfoiowc:
The rated maximum voltage of a circuit breaker is the highest rms (root mean square) voltage, three-phase or single-phase, at ,çhjch it is designed to perform. The circuit breaker shall be rated at one or more of the following maximum voltages: 1058 V. 730 V. 635 V. 508 V. or 254 V. For fused circuit breakers, the 635 V rated maximum voltage becomes 600 V to match the fuse rating
8. Test procedures
8.2 Test values
8.2.3 Test voltage values
Change item a) as follows:
a) Primary circuit of a new, completely assembled circuit breaker. 2200 V.
1) 2200 V for circuit breakers with maximum voltage rating of 635 V and below
2) 3000 V for circuit breakers with maximum voltage ratings of above 635 V.
9. Application guide
9.1 General
9.1.4 Short-circuit current
9.1.4.3 Motor contribution
Change lien, b as follows:
b) For nominal system voltages of 240 V to 1000 V600 V. it should be assumed that the load is 100% motor load and, in the absence of exact information, that 25% of the motors are synchronous and 75% induction. This corresponds to an equivalent symmetrical contribution of approximately four times the full-load current.