System Description
6
2.5
DC-to-DC Converter
The DC to DC converter utilizes energy from the battery system and raises the DC voltage to the opti-
mum operating voltage for the inverter. This allows the inverter to operate continuously at its opti-
mum efficiency and voltage, thus increasing reliability.
2.6
Battery
The S4K5U utilizes valve-regulated, nonspillable, lead acid batteries. To maintain battery design
life, operate the UPS in an ambient temperature of 20°C to 25°C (68°F to 77°F). Optional external
battery cabinets are available to extend battery run times.
2.7
Dynamic Bypass
The S4K5U provides an alternate path for mains power to the connected load in the unlikely event of
a UPS malfunction. Should the UPS have an overload, overtemperature, or UPS failure condition, the
UPS automatically transfers the connected load to bypass. Bypass operation is indicated by an audi-
ble alarm and illuminated amber Bypass LED (other LEDs may be illuminated to indicate the diag-
nosed problem). To manually transfer the connected load from the inverter to bypass, press the
Standby button once.
NOTE
The bypass power path does NOT protect the connected equipment from disturbances
in the mains supply.