Sices D-PRO, Техническое руководство

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34 D-PRO Protection relay Technical Manual
The controller measures the power supplied by the genset on the three currents on side B.
The protection activates if the total active power is positive and higher than the threshold set
in P.0380 (percentage of P.0106) for the time configured in P.0381.
Type: Alarm
Related parameters: P.0382 Maximum reactive power threshold (% compared with P.0106)
P.0383 Maximum reactive power delay
To disable: P.0383 =0
The protection is enabled only in case of absence of the disabling digital input (usually
combined to the circuit breaker status).
The controller measures the reactive power (exported) by the genset on the three currents on
side B.
The protection activates if the reactive power is positive and it is higher than the threshold set
in P.0382, consecutively for the time configured in P.0383.
Type: Alarm
Related parameters: P.0101 Genset phase number
P.0106 Genset rated power
P.0107 Genset rated current
P.0366
I2 current threshold for negative sequence (%)
P.0367 Delay for negative sequence
P.0109
Nominal phases sequence
To disable: P.0326=0
The protection is enabled only for three-phase systems (P.0101=3) and if the current
measurement is connected to the genset (current transformers on the genset). It is enabled
only in case of absence of the disabling digital input.
The negative sequence current “I2” is calculated as 1/3 module of the vector sum of three
phase currents, with a 120° rotation of L2 phase in one direction and a 120° rotation of L3
phase in another direction (depending on the rotation sense). If the load and the cos(ɸ) on the
three phases is balanced, the “I2” current is 0. Basically, it is an index of load unbalance, which
considers also the current vectors angles, not only the modules.
It activates when the current “I2” is higher than threshold set in P.0366, consecutively for the
time configured in P.0367. The threshold P.0366 is expressed in percentage compared to the
rated current: see P.0107 to define the rated current from parameters P.0101, P.0102 and
P.0106.
Type: Alarm
Related parameters: P.0101 Genset phases number
P.0328 Genset phases sequence (required)
P.0329 Delay for genset phases sequence
To disable: P.0329=0
It is enabled only in case of absence of the disabling digital input.