Marathon TSC 900 - TSC 900 Typical Connection Diagram

TSC 900 TRANSFER SWITCH CONTROLLER
PM 151 REV 1 15/10/08 Thomson Power Systems
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5.12.6. OVER VOLTAGE PICKUP
Set to the desired source over voltage pick-up set point as expressed in percentage of
nominal system voltage. The pick-up set point is the value which the internal sensor
energizes to an abnormal state when any one phase of the supply rises above the set
point. A over voltage condition will be triggered following expiry of the over voltage time
delay setting.
5.12.7. UNBALANCED VOLTAGE LATCH
When the phase unbalance latch feature is enabled, this programming prompt will
affect operation of the retransfer sequence following an abnormal phase balance
condition. Two retransfer modes of operation are selectable as follows:
NO (DISABLED): The controller will automatically initiate a retransfer sequence once
the original sources phase unbalance condition returns within nominal limits
as programmed.
YES (ENABLED): The controller will not automatically initiate a retransfer sequence
following a phase unbalance alarm condition but the alarm will latch in. To
initiate a re-transfer sequence, an operator must manually reset the phase
unbalance alarm condition by pressing the ALARM RESET button on the GHC
ALARMS page.
5.12.8. PHASE UNBALANCE DELAY (PICKUP)
Select the desired source phase unbalance time delay setting. The setting is entered
in seconds. If no delay is required, set this time delay to zero.
5.12.9. PHASE UNBALANCE DROP OUT
Set to the desired phase unbalance drop out set point as expressed in percentage of
nominal negative sequence voltage. The drop-out set point is the value which the
internal sensor de-energizes to a normal state when all phases of the source falls a
below the set point.
5.12.10. PHASE UNBALANCE PICK UP
Set to the desired source phase unbalance pick-up set point as expressed in
percentage of nominal negative sequence voltage. The pick-up set point is the value
which the internal sensor energizes to an abnormal state when any one phase of the
supply rises above the set point. A phase unbalance condition will be triggered
following expiry of the phase unbalance time delay setting.
5.12.11. UNDER FREQUENCY DELAY (DROPOUT)
Select the desired utility under frequency time delay setting. The setting is entered in
seconds. If no delay is required, set this feature to zero.