Operation
28
•Battery Test (MMU Only)—The optional battery test screen allows the operator to perform
manual battery tests to determine the general condition of the battery system. The results of the
last 10 tests are recorded in non-volatile storage and can be retrieved through the battery test
results screen.
•Battery Temp Compensation Charging (MMU Only)—The optional battery temperature
sensing unit, when installed, automatically reduces the float charge voltage in response to
increases in battery temperature. The nominal float voltage is 540VDC (2.25 volts per cell) at
25°C. This float voltage is automatically reduced 5VDC for each temperature rise of 5°C. The LCD
indicates whether the temperature compensation circuit is active.
3.2.2 SCC Monitor/Mimic Display Screen
From SCC Master Menu move the highlighted cursor to MONITOR/MIMIC DISPLAY. Press the
Select pad and the Monitor/Mimic screen is displayed.
The Monitor/Mimic display screen is a simplified block diagram of the UPS system. This screen gives
the operator an overall view of the power flow through the UPS system. The screen consists of three
major sections: the input/UPS metering section, the load metering section and the status and alarm
message areas. The metered parameter values on the Monitor/Mimic screen are updated at one-sec-
ond intervals.
Figure 14 SCC Monitor/Mimic display screen
Input Metering Displays
Item 1 - Bypass Input: This block displays the bypass input voltage and the bypass input frequency.
The System Bypass Breaker is shown to the right of this block. The status of the circuit breaker is
illustrated as open or closed.
Item 2 - UPS Input Pwr: This block displays the input voltage to the UPS modules. This data is
received serially from the modules.
Output Metering Displays
Item 3 - UPS Ratings: The SCC current rating is specified at the top of this block. The UPS system
output voltage and frequency are also displayed in this block. The UPS Output Breaker is shown to
the right of this block. The status of the circuit breaker is illustrated as open or closed.
Item 4 - Load: This block displays the total output power to the critical load in kVA and kW. The
critical load current per phase is also displayed in this block. Note that kW is not displayed when the
load is on the bypass line.
The load block also indicates the number of modules connected and whether the UPS system is oper-
ating in the redundant or non-redundant mode.
During an overload condition, the time remaining before shutdown or transfer is displayed at the bot-
tom of the load box.
NOTE
All voltage readings are phase-to-phase measurements (A-B, B-C and C-A). All current
readings are phase measurements (A, B and C).
UPSINPUT PWR
480V 480V 480V
UPSRATINGS
A-B B-C C-A
480V 480V 480V
60.0Hz
SCCB1600
OUTPUTVOLTAGE
BYPASSINPUT
A-B B-C C-A
480V 480V 480V
60.0Hz
LOAD
ABC
627KVA / 502 KW
755A 755A 755A
3OF 3 MODULES
CONNECTED
REDUNDANT
A-B B-C C-A
OKto Transfer
StaticSwitch Connected
2
5
4
3
67
1
MOD1 ONLINE
MOD2 ONLINE
MOD3 ONLINE
©1989-2003