Specifications

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2.1.6 Optional features:
a. Remote monitor panel.
b. Maintenance Bypass Switch (MBS).
c. Input AC breaker (100 ~ 225 kVA).
d. Input Isolation Transformer (Standard option on 480V input-208/120V
output units).
2.2 Modes of Operation
The UPS shall be designed to operate continuously at rated capacity as an on-line,
automatic system in the following modes:
2.2.1 Normal - The inverter continuously supplies AC power to the critical load. The
converter converts commercial AC power to regulated DC power which then
serves as the inverter input and, simultaneously, as a float charge input to the
storage battery.
2.2.2 Emergency - In the event of a commercial AC power failure, the inverter shall
derive its input from the system battery, thus providing uninterrupted power to the
critical load. This transition shall be accomplished without any switching or
coupling, and with no interruption of power to the critical load from either a
failure or restoration of the commercial AC power.
2.2.3 Recharge - Subsequent to restoration of commercial AC power, the converter
shall automatically reactivate and provide DC power to the inverter,
simultaneously recharging the system battery. This occurs automatically and
without interruption to the critical load.
2.2.4 Bypass - In the event that the UPS must be taken off line due to an overload
condition or UPS failure, the critical load shall be transferred to the bypass source
via the static switch without interruption of power to the critical load. A
paralleling, wrap-around contractor shall be used to maintain the bypass source.
The static switch shall only be utilized for automatic emergency transfers. A re-
transfer from bypass to inverter shall be performed automatically in overload
conditions. A re-transfer shall be inhibited if satisfactory synchronization of the
inverter and bypass is not accomplished. The use of the static switch shall not be
required during the manual or automatic re-transfer process, thus increasing
reliability.
2.2.5 Remote - The UPS logic shall be capable of remote operation allowing activation
of the following functions from a remote location:
a. Inverter stop.
b. Inverter start.
e. Emergency power off.
2.2.6 Maintenance Bypass – The UPS system shall be equipped with an external MBS
to allow safe and reliable maintenance of the UPS. The MBS shall be of the