FUNCTION CHARACTERISTICS
337
A
: electrical angle
t
CB-CLOSE
: CB closing time
t
MEAS
:protective relay measuring time (acquisition time + measure + output relay)
∆f: slip frequency in Hz
Eg:, with following values:
t
CBCLOSE
: CB closing time = 80 ms
t
MEAS
: protective relay measuring time (acquisition time + measure + output relay) = 40 ms
f
1
: V1 frequency = 50 Hz
f
4
: V4 frequency = 50.2 Hz
∆f: slip frequency = 0.20 Hz
To make sure that the circuit breaker closing takes place under conditions of perfect synchronism
relay must send the close command when the phase difference is = 8.6 degrees and V4 is lagging
behind V1.
XMR-D EQUIPMENT MANUAL
Ed. 2.9 - 02/2021