BECKWITH ELECTRIC M-3425, Instruction Book

Page: 98 / 225

Operation – 3
3–9
3.4 Target History
The M-3425 Generator Protection Relay has the
ability to store the last twenty-four target conditions
in a nonvolatile manner. A target is triggered
whenever an output is operated (OUT1–OUT8). A
second function attempting to operate an output
(which is already operated) will not trigger a new
target, since no new output has been operated or
closed. If the second function operation closes a
different, unoperated output, a new target will be
triggered. A target includes:
• an indication which function(s) have
operated, and timers expired (operated),
• status information which indicates any
function that is timing (picked up),
• individual phase element information at
the time of the trigger, if the operating
function was a three phase function,
VIEW TARGET HISTORY
TRGT clear
VIEW TARGET HISTORY
1 Target number
TARGET 1
01-JAN-2001 12:27:35.125
TARGET 1
08
05 01
TARGET 1
I3 I1
TARGET 1
-OPERATE TARGETS-
TARGET 1
27#1 PHASE UNDERVOLTAGE
TARGET 1
PHASE A=X B= C=
TARGET 1
-PICKUP TARGETS-
TARGET 1
27#1 PHASE UNDERVOLTAGE
This screen gives access to the target history, and also allows the
user to clear the target history record from memory.
Using up and down buttons, user may select which particular target
to view from the last 24 recorded triggers.
This screen gives the date and time tag of the selected target.
This screen displays operated outputs.
This screen displays operated inputs at time of trip.
The following screens display the timed out or “operate” functions.
This screen displays the specific function which timed out and triggered
the target.
This gives the phase information for the displayed function at time
out.
The following screens display the timing on “picked up” functions
when the target was recorded.
• phase currents at the time of operation
• neutral current at the time of operation,
• input and output status, and
• a date/time tag.
When a target is triggered, the front panel TARGET
LED will light, indicating a recent event. If the
optional M-3925 Target Module is present, the
corresponding function LED will be lit. If the optional
M-3931 HMI module is available, a series of screens
will be presented, describing the most recent
operation. This information is also available remotely
by using the IPScom
® communication package.