18 Installation Guide APC Silcon 240-320kW 480V UPS
990-4049
External Connection
4.1.4 Dual and Single Utility Supply
The UPS is fitted with dual utility input as standard. If dual utility is not available or not
needed, a small modification has to be made. See section 4.1.5 switching from dual to single
utility input.
WARNING!
UPS units contain hazardous AC and DC voltages. Only qualified electricians should install UPS,
AC line and external batteries, and must be familiar with batteries and battery installation.
Before installing, maintaining or servicing the UPS, shut off the UPS and disconnect all sources
of AC and DC power.
As the UPS has no built-in disconnection devices to switch off external AC and DC input power,
ensure that disconnection devices are provided as separate parts in connection with the
installation!
The installer must provide each external disconnecting device for this UPS system with labels
with wording as follows:
“Isolate the Uninterruptible Power Supply (UPS) as instructed in this guide
before working on circuit”
AC and/or DC voltage will always involve a potential risk of AC voltage at UPS output generated
from either batteries or utility. To avoid equipment damage or personal injury, always assume
that there may be voltage at UPS output.
This system is equipped with an auto-start function. If activated the system may start without
warning. Refer to “Programming Parameters” for information on de-activation.
TEST BEFORE YOU TOUCH!
To reduce the risk of fire or electric shocks, install the UPS and external batteries in a
temperature and humidity controlled indoor area, free of conductive contaminants.
UPS batteries are high-current sources. Shorting battery terminals or DC terminals or DC
busbars can cause severe arcing, equipment damage and injury. A short circuit can cause a
battery to explode. Always wear protective clothing and eye protection and use insulated tools
when working with working near batteries.
CAUTION!
This unit contains components sensitive to electrostatic discharge (ESD). If you do not follow the
ESD procedures, you may cause severe dammage to electronic components.