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2.1 Introduction
The UPS can be considered to be in one of three operating
conditions:
§
Normal operation
- All relevant power switches and circuit breakers
closed, the load is powered by the UPS.
§
On Maintenance Bypass
- UPS shut down but the load connected
to the unprotected mains via the Maintenance Bypass Supply
line.
§
Shutdown
- All power switches and circuit breakers open no load
power.
This chapter contains instructions which enable you to switch between
the three above conditions, to carry out a RESET after a fault transfer
and how to switch OFF the inverter.
Note 1:
All the user controls and indicators mentioned in these procedures are
identified in chapter 1. Some of the diagrams are repeated here to
assist in understanding the procedures.
Note 2:
The audible alarm may annunciate at various points in these
procedures. It can be canceled at any time by pressing the 'Alarm
Reset' push- button.
Note 3:
The 7400-M series UPS incorporates an optional automatic boost
charge facility which can be used in systems containing conventional
flooded lead-acid batteries. If this type of battery is used in your
installation you may notice that the battery charger voltage may be
greater than its nominal (432V DC for 380V AC, 446V DC for 400V
AC and 459 AC for a 415V AC system) when the mains supply
returns from a prolonged outage. This is the normal response of the
boost charge facility: the charger voltage should return to normal after
a few hours.
Chapter 2 – Operating Instructions
2.1.1
General Notes
