IEEE C37.06:2009 pdf free download

IEEE C37.06:2009 pdf free download.IEEE Standard for AC High-Voltage Circuit Breakers Rated on a
Symmetrical Current Basis—Preferred Ratings and Related Required Capabilities for Voltages Above 100o v.
5.1 Information for Table 1, Table 2, and Table 3
(Numbers in parenthesis in the tables refer to the following correspondingly numbered items.)
(I) The voltagc ratings arc based on ANSI C84. 1.2006 LB2] where applicable and arc the maximum voltages for which the circuit breakers are designed for and are the upper limit for operation.
(2) The ratings in this column are the maximum time interval to be expected during a circuit-breaker opening operation between the instant of energizing the trip circuit and the interruption of the main circuit on the primary arcing contacts undcr certain specified conditions. The values may be exceeded under certain conditions as specified in lliL± Std C37.04b-200X. subelause covering rated interrupting time.
(3) For 60 Hz, rated closing and latching current (kA, peak) of the circuit breaker is 2.6 times the rated short-circuit current, (If expressed in terms of kA. rms total current, the equivalent value is 1.55 times rated short-circuit current.)
For 50 Hz, the kA peak is 2.5 times the rated short-circuit current and the rms total current is 1.47 times the rated short circuit current.
(4) These values of TRV are changed from the previous publication of ANSI C37.06-2000. IEEE agreed to use the circuit-breaker Si (cable connected circuit breakers) values from IEU 62271-100:2008 (B5J, and the IEC agreed to use the circuit-breaker S2 (overhead connected circuit breakers) values from IEEE. The values are also changed by conversion of the former NEMA/ANSI exponential-cosine values to the two-parameter values. Several IEEE papers have been published on behalf of the Switchgcar Committee explaining the harmonization efforts between IEC and IEEE. Refer to IEC 62271-100:2008 [135] and Dufoumet and Montillet [134].
(5) Synthetic tests can be performed to prove the capability of values off3 in column 6 of Table 3.
(6) The traditional North American continuous current rating of 1200 A has been retained in this standard. while IEC prefers the continuous current rating of 1250 A. It is possible that the continuous current rating might be changed to 1250 A in a future edition.