BECKWITH ELECTRIC M-4272, Instruction Book

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M-4272 Digital Motor Bus Transfer System
TCM
CCM
ISSL
†
Select the greater of these accuracy values. Accuracy applies to sinusoidal voltage with constant amplitude and
frequency.
FUNCTIONS (Cont.)
Setpoint
Ranges
Increment Accuracy †
Bus VT Fuse-Loss Detection
Delta Pickup* 5 to 25 V 1 V .05 V or 2%
Time Delay** 1 to 8160 Cycles 1 Cycle 3 Cycles or 1%****
Blocking Drop Out
Time Delay***
1 to 300 Cycles 1 Cycle 3 Cycles or 1%****
* Mismatched voltage of the motor bus in respect to the connected source.
** This time delay is for the programmable alarm output.
*** This is the time it takes to drop out (reset) the block transfer after no Bus VT fuse-loss is detected.
**** The pickup and time delay accuracies apply to 60 HZ models at a range of 57 to 63 Hz, and to 50 Hz
models at a range of 47 to 53 Hz. Beyond these ranges, the time delay accuracy is 6 Cycles or 0.75% for the
bus frequency down to 25 Hz. The time delay accuracy is
O 20 Cycles or 1% for the bus frequency at a range
of 5 to 25 Hz.
If the bus VT fuse-loss is detected, the user must either select block transfer or initiate the Fixed Time
Transfer.
Bus VT fuse-loss output is intiated from internally generated logic.
Trip and Close Circuit Monitor
Trip Circuit Monitor
TCM-1 Time Delay 1 to 8160 Cycles 1 Cycle 1 Cycle or 1%
TCM-1 Dropout Time Delay 1 to 8160 Cycles 1 Cycle 1 Cycle or 1%
TCM-2 Time Delay 1 to 8160 Cycles 1 Cycle 1 Cycle or 1%
TCM-2 Dropout Time Delay 1 to 8160 Cycles 1 Cycle 1 Cycle or 1%
Close Circuit Monitor
CCM-1 Time Delay 1 to 8160 Cycles 1 Cycle 1 Cycle or 1%
CCM-1 Dropout Time Delay 1 to 8160 Cycles 1 Cycle 1 Cycle or 1%
CCM-2 Time Delay 1 to 8160 Cycles 1 Cycle 1 Cycle or 1%
CCM-2 Dropout Time Delay 1 to 8160 Cycles 1 Cycle 1 Cycle or 1%
The CCM/TCM inputs are provided for monitoring the continuity of the Source 1 and Source 2 trip and close
circuits. The inputs can be used for nominal trip/close coil voltages of 24 V dc – 250 V dc. Trip and closing
circuit monitoring are performed in the active breaker status only (trip circuit supervision when breaker is
closed and close circuit supervision when breaker is open.) Both the DC supply and continuity for each of the
circuits are monitored.
ISSLogic ®
ISSLogic uses control/status input status, system status, function status, output contact close
signals to develop 6 programmable logic schemes.
Time Delay #1-#6 0 to 65500 Cycles 1 Cycle 1 Cycle or 1%
Dropout/Reset Time Delay
#1-#6 0 to 65500 Cycles 1 Cycle 1 Cycle or 1%
60FL