Specifications

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4.4.2. Automatic Re-transfers
In the event that the critical load must be transferred to the bypass source due
to an overload, the UPS system logic shall monitor the overload condition
and, upon the overload being cleared, perform an automatic re-transfer back
to the inverter output. The UPS system logic shall only allow a re-transfer to
occur three times within a one minute period. Re-transfers shall be inhibited
on the fourth transfer due to the likely hood of a recurring problem at the
UPS load distribution. The re-transfer of load to the inverter shall also be
inhibited due to the limitations set in section 3.3. All retransfers will be
inhibited if the inverter and static bypass line are not synchronized.
4.4.3. Manual Transfers
The UPS shall be capable of transferring the critical load to/from the bypass
source via the front control panel. current to the inverter. Manual transfers
will be inhibited if the inverter and static bypass line are not synchronized.
4.4.4. Static Switch
The static switch shall be a high speed transfer device comprised of naturally
commutated SCR's.
5. OPERATOR CONTROL PANEL
5.1. Operator Controls
The operator control panel shall employ the use of a touch screen interface which
allows lock-out of all UPS control functions for security (the Emergency Power Off
function shall not be locked-out). The operator interface shall provide the
following:
a. UPS start-up procedure
b. UPS shutdown procedure
c. Emergency Power Off (EPO)
d. Audible alarm silence
e. System status levels