Operation
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User Guide APC BC300 Series 40kW 208/450/480V UPS 7
3.1 Operation Modes
The display automatically indicates which mode the unit is operating in. See Table 1 below for
sample display messages and an explanation of each.
Table 1: Operating Modes
Sample Display
Mode
Operation Mode Description
Normal Operation
load power ##%
The UPS is in the normal operation mode. During normal operation,
utility (AC line) passes through the UPS and to the load. The inverter
regulates the output and charges the batteries. The UPS measures
all three phases, and the display reads out the% load of the highest
loaded phase.
Battery Operation
time ## minutes
When AC input is out of tolerance (outside programmed limits), the
UPS is running in battery mode. The main static switch is open, and
the inverter is powered from the batteries. The power is then fed to
the loads. If the batteries are depleted, the unit will switch to stand-
by mode (see below) and wait for utility to return in tolerance. If auto-
start is programmed to “ON,” the unit will automatically start about
30 seconds after utility has returned. If auto-start is programmed to
“OFF,” you must start the unit manually by pressing the green
button inside the front door. (See the “Parameter Settings” section in
this User Guide.)
Bypass Operation The AC input passes unregulated through the bypass static switch,
through the main transformer, and to the loads. The UPS’ inverter is
in stand-by and is synchronized to the utility, ready to transfer the
unit to battery operation if utility voltage is out of tolerance.
Economy Mode The unit has been programmed to operate in economy mode. The AC
power flows in bypass, and the UPS will periodically transfer to
normal operation to charge the batteries (at 7-day intervals by UPS
default). The inverter is in stand-by and is synchronized to utility,
ready to transfer to battery operation if utility voltage is out of
tolerance. The output voltage is not regulated in this mode, but
efficiency increases. Call APC Technical Support or your nearest
APC office for more information on programming your APC BC300
Series UPS for Economy Mode.
** Stand-by ** Both static switches are open. The unit is not supplying output
voltage.