Woodward GCP-20 Series User Manual

Manual 37128A GCP-20 Series - Genset Control
Page 118/190 © Woodward
Mains Frequency Monitoring
Monitoring the mains frequency is absolutely vital if a generator is operated in conjunction with the infinite grid.
In the event of mains failure (e.g. utility power outage) the generator that is operating in parallel with the utility
must be automatically disconnected from the mains. Decoupling from the mains only occurs when both power
circuit breakers (MCB and GCB) are closed.
The limit values configured below are utilized for the assessment emergency power operations if the following
parameters are enabled. The parameters below define if the mains are or aren’t present. The breaker opening
times do not affect these parameters.
Function: "Mains frequency not within the permissible range" - The mains frequency exceeds the limit values
configured for overfrequency or underfrequency. The power circuit breaker that disconnects from the mains is
immediately opened. The prerequisite of mains frequency monitoring is that the generator is operating in mains
parallel (the MCB and GCB are both closed).
Parameter 173
Mains frequency
monitoring ON
Mains frequency monitoring ON/OFF
ON................Monitoring of the mains frequency will be performed. The subse-
quent parameters of this function are displayed.
OFF..............Monitoring is disabled, and the subsequent screens of this function
are not displayed.
Parameter 174
Mains overfreq.
f > 00.00Hz
Mains overfrequency threshold value 40.0 to 85.0 Hz
If this threshold value has been exceeded for at least the delay time (Para-
meter 175), the following alarm class is issued. Depending on the configured mains
decoupling procedure, the GCB, MCB, or an external CB will be opened.
Issuing of class F0 alarm
Parameter 175
Mains overfreq.
Delay time 0.00s
Mains overfrequency delay 0.02 to 9.98 s
For the control unit to recognize a mains overfrequency fault condition, the thresh-
old value configured in
Parameter 174 must be exceeded without interruption for
this period of time.
Parameter 176
Mains underfreq.
f < 00.00Hz
Mains underfrequency threshold value 40.0 to 85.0 Hz
If the current value has been fallen below this threshold value for at least the delay
time (
Parameter 177), the following alarm class is issued. Depending on the con-
figured mains decoupling procedure, the GCB, MCB, or an external CB will be
opened.
Issuing of class F0 alarm
Parameter 177
Mains underfreq.
Delay time 0.00s
Mains underfrequency delay 0.02 to 9.98 s
For the control unit to recognize a mains underfrequency fault condition, the
threshold value configured in
Parameter 176 must be exceeded without interruption
for this period of time.

Woodward GCP-20 Series Specifications

General

Brand	Woodward
Model	GCP-20 Series
Category	Control Unit
Language	English