Capstone Turbine Corporation
Model C65 Hybrid UPS User’s Manual
400027 Rev A (July 2010)
Page
29 of 66
Capstone reserves the right to change or modify, without notice, the design, specifications, and/or contents of this document without
incurring any obligation either with respect to equipment previously sold or in the process of construction.
Returning a Hybrid UPS Unit to Service
Once a Hybrid UPS system has been taken out of service by disabling it from the
MultiPac, it can be restored to service by simply re-enabling it. This can be done in several
ways:
•
UPS Controller Touch Screen Display – If the touch screen display panel is dark,
touch it anywhere to activate it. When the screen becomes active, enter the
Maintenance screen using password, and press the MultiPac Enable button for the
desired Hybrid UPS unit.
•
UPS Controller BMS Interface – the UPS Controller is able to communicate with a
building management system or other external control equipment, and receive a
remote command to enable a Hybrid UPS unit. Refer to specific instructions
provided by the building management system integrator.
Once the individual Hybrid UPS system has been re-enabled as part of the MultiPac, it will
start acknowledging commands from the UPS Controller and will synchronize its output to
fit the desired operating mode. Utility Input and Load Output power connections will be
made automatically, and loads will then be shared between all available Hybrid UPS
systems.
NOTE
Make sure any power connections that were isolated for service reasons
have been reestablished to make power available to the critical loads,
utility grid connections, and external energy storage system.
Transfer to/from Utility Power
If the Hybrid UPS system is operating in UPS Mode or High Efficiency Mode, it will attempt to
maintain synchronism of the load output to the utility input voltage in both frequency as well as
phase relationship. Therefore, during normal operation it is possible to seamlessly transfer the
critical load from the output of the Hybrid UPS systems to the utility source, or vice versa, using
a closed transition scheme. Automatic Transfer Switches (ATS) are available with the ability to
make a momentary closed transition when voltages and phase relationship of the two sources
are within preset limits. Neither the Hybrid UPS systems nor the UPS Controller have direct
control over this transfer, and do not need to control the ATS for proper system operation. The
UPS Controller will accept input signals from an external transfer scheme in order for its local
display to provide an overview of the state of the system. Refer to instruction provided by the
building management system integrator or equipment installer for how to activate the transfer
scheme.
Transfer from Hybrid UPS to Utility Power
When a transfer scheme moves the critical load from the output of the Hybrid UPS systems to
the utility source, the Hybrid UPS systems will see a load drop, but will continue to supply
voltage to their load outputs, regardless of whether they are operating in UPS Mode or High
Efficiency Mode. If the system was in the High Efficiency Mode, all power from the turbine
generators will be delivered to the utility power connection. If this transfer to utility power is only
intended to be temporary, the Hybrid UPS systems can be left in the desired operating mode
where they will remain ready for retransfer of the critical loads. If the transfer was for service or
other reasons, the system can be shut down as described below.
