44 Chapter 5 Operating Instructions
Chapter 6 Operating Instructions
Warning: Hazardous mains voltage and/or battery voltage present behind the protective cover
The components that can only be accessed by opening the protective cover with tools cannot be operated by user.
Only qualified service personnel are authorised to remove such covers.
6.1 Introduction
The LIEBERT APM UPS operates in the following 3 modes listed in Tab.
6
-
1
. This section describes various kinds of
operating procedures under each operating mode, including transfer between operating modes, UPS setting and
procedures for turning on/off inverter.
Operating mode
Descriptions
Normal mode
NORMAL
UPS powers the load
Bypass mode
BYPASS
The load power supply is provided by the static bypass.This mode can be regarded as a
temporary transition mode between the normal mode and maintenance bypass mode, or a
temporary abnormal operating status
Maintenance Mode MAINT
UPS Shuts down, the load is connects to the mains vie Maintenance bypass. NOTE: in this
mode the load is not protected against abnormal mains
Tab.
6
-
1
UPS Operating mode
Note:
1. Refer to
Chapter 7
Operator Control And Display Panel
,
for all the user operating keys and LED displays.
2. The audible alarm may annunciate at various points in these procedures. It can be cancelled at any time by
pressing the ‘SILENCE ON/OFF’ push-button.
3. The UPS function can be set via maintenance software. However, the setting and commissioning must be done by
maintenance engineers trained by Emerson.
6.1.1 Power Switches
The UPS rack system only has a maintenance bypass isolating switch, and all the other transfers are processed
automatically by internal control logics.
6.2 UPS Startup
Do not start the UPS until the installation is completed, the system has been commissioned by authorized personnel
and the external power isolators are closed.
6.2.1 Start-Up Procedure
This procedure must be followed when turning on the UPS from a fully powered down condition.
The operating procedures are as follows:
1. Open the external power switch. Open the UPS door, connect the power supply cables and ensure the correct
phase rotation.
Warning
During this procedure the UPS output terminals are live.
If any load equipment is connected to the UPS output terminals please check with the load user that it is safe to apply power:If the
load is not ready to receive power then ensure that it is safely isolated from the UPS output terminals.
Summary of Contents for Liebert APM
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