HV & LV breaker
HV & LV breaker
(OP)
I would like to know the standard time constants or X/R ratios of HV and LV circuit breaker. I am presently trying an IEC909 based short circuit calculation and have a value of X/R = 14 (for 50 Hz) for HV breakers. For LV breakers,I have a table with list of power factors, multiplication factors depending upon the capacity of switchear. Can someone guide me to the relevant ard/links for me to have a better understanding?






RE: HV & LV breaker
Mike
RE: HV & LV breaker
Another question:
In HV switchgears the calculated symmetrical rms and peak are much lesser than the switchgear withstanding ability. However the calculated X/R ratio at this HV switchgear is greater than the X/R ratio as per IEC, ie. 14.
I would like to know whether any derating has to be applied on the switchgear rating?
RE: HV & LV breaker