Manual 37351A
MFR 11 Packages - Protection Relay
Page 34/59
© Woodward
Protection
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Overvoltage Monitoring
Function
: "Voltage not within permissible limits"
The monitored voltage in at least one phase is not within the configured permissible limits for overvoltage. The
alarm message "
Overvolt.1
" or "
Overvolt.2
" will be displayed. This message
cannot
be suppressed with
the discrete input "Blocking of protective functions / remote acknowledgement".
Overvoltage
Monitoring ON
Overvoltage monitoring
ON/OFF
ON
................Overvoltage monitoring is enabled. The subsequent screens of this
function are displayed.
OFF
..............Overvoltage monitoring is disabled. The subsequent screens of this
function are not displayed.
Screen for
Phase-neutral
:
Overvoltage 1
(Phase-N) >000V
Screen for
Phase to phase
:
Overvoltage 1
V(ph-ph) >000V
Threshold
(Phase-phase) [1] 20 to 150 V; [4] 20 to 520 V; [7] 20 to 900 V
overvoltage level 1
(Phase-neutral) [1] 10 to 87 V; [4] 10 to 300 V; [7] 10 to 520 V
Overvoltage (level 1) is defined by this parameter. If this limit is reached or ex-
ceeded, the unit outputs the message "
Overvolt.1
". If a relay was assigned to
this function in the relay manager, that relay will be energized.
Overvoltage 1
Delay 00.00s
Pickup delay, level 1
0.02 to 99.98 s
In order to initiate an overvoltage (level 1) alarm, the measured voltage must ex-
ceed and remain above the configured threshold without interruption for at least the
period of time specified in this screen.
Screen for
Phase-neutral
:
Overvoltage 2
(Phase-N) >000V
Screen for
Phase to phase
:
Overvoltage 2
V(ph-ph) >000V
Threshold
(Phase-phase) [1] 20 to 150 V; [4] 20 to 520 V; [7] 20 to 900 V
overvoltage level 2
(Phase-neutral) [1] 10 to 87 V; [4] 10 to 300 V; [7] 10 to 520 V
Overvoltage (level 2) is defined by this parameter. If this limit is reached or ex-
ceeded, the unit outputs the message "
Overvolt.2
". If a relay was assigned to
this function in the relay manager, that relay will be energized.
Overvoltage 2
Delay 00.00s
Pickup delay, level 2
0.02 to 99.98 s
In order to initiate an overvoltage (level 2) alarm, the measured voltage must ex-
ceed and remain above the configured threshold without interruption for at least the
period of time specified in this screen.
Overvoltage
Hysteresis 00V
Hysteresis for the overvoltage monitoring, levels 1 + 2
0 to 99 V
In order to prevent system fluctuations from continually initiating overvoltage
alarms (both levels), a lower release point is defined here. If the control monitors
the voltage above the permissible limit, the voltage must drop below that threshold
and the voltage level defined here for the fault condition to be recognized as no
longer existing.
Example: If a 480 V system has an overvoltage limit of 510 V and a hysteresis of
10 V, the monitored voltage for an overvoltage alarm must drop below 500 V to re-
set the alarm.
