13
Multiple UPS Operation (Parallel)
(continued)
Maintenance Bypass Mode
In this mode, the Manual Maintenance Procedure (On Bypass) has been performed in order to pass-through filtered AC input power (from a reserve
AC input source) to connected equipment loads while allowing maintenance on the UPS power module. (Note: since the power module's inverter
is bypassed in this mode, the UPS will not be able to switch to Back-Up Mode in the event of a power failure.) After the Manual Maintenance
Procedure (Off Bypass) has been performed, the power module automatically reactivates the inverter and switches back to the mains AC input
source to support connected equipment loads.
Optional Parallel Configuration (Hot Standby Redundancy and Common Battery)
Hot Standby Redundancy
In this configuration, one or more UPS power modules serve in a “hot standby” role in order to increase the availability of connected equipment
by reducing the chances that a failure of one UPS will impact output power. During normal conditions, the UPS in a “hot standby” role does not
support the connected equipment load; however, during a UPS failure, the UPS in a “hot standby” role automatically supports (through activation
of the static switch) the connected equipment load. The output of the UPS in a “hot standby” role is connected to the reserve power input of another
UPS power module. In order to reduce installation costs, users can use one UPS power module in a “hot standby” role for up to seven additional
UPS power modules within a parallel configuration.