Uninterruptible Power Supplies PowerWAVE 8000DPA RI, User Manual

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4: Operation
4-8
UPS338-01-00 PowerWAVE 8000-RI DPA User Manual Dated 5 April 2013
within 3 to 5 msec – this is valid for single and parallel module systems. The battery charger remains active in
this mode.
Although this mode of operation offers greater efficiency than the On-Line mode, it is recommended only if
the loads can tolerate interruptions of 3 to 5 ms – which is the transfer time from Bypass mode to On-Line
mode.
4.4.3 Maintenance Bypass Mode
Figure 4.4 Maintenance Bypass Mode
Each cabinet is fitted with a Maintenance Bypass switch (IA1) which, when closed, connects the UPS
Module(s) output terminals directly to the UPS bypass mains supply. This facility enables the UPS system to
be shut down for maintenance or repair whilst maintaining the load on the raw (unprotected) bypass supply.
Maintenance Bypass switch (IA1)
The Maintenance Bypass mode is effected by means of the IA1 BYPASS SWITCH on the front of the UPS:
WARNING:
ALL the UPS Module in a parallel module system must first be selected to the
Bypass mode before the Maintenance Bypass is operated closed.
Switch IA1 Effect
ON
(CLOSED) Maintenance Bypass-Switch Closed (Load on bypass mains)
LCD-indication:
MAINTENANCE BYP CLOSED
.
LED Indicators will indicate as shown in the table below.
OFF
(OPEN) Bypass-Switch Open – Normal operating condition (Load on inverter)
LCD-indication
MAINTENANCE BYP OPEN
.
LED Indicators will indicate as shown in the table below.
LED Indicator Switch IA1 ON Switch IA1 OFF
LINE 1
Green Green
LINE 2
Green Green
BYPASS
Green ON
INVERTER
RED ON
BATTERY
Green Green
CAUTION: If the UPS is operating in the Maintenance Bypass mode the load will not be
protected in the event of a mains failure. It is therefore strongly recommended to switch over to
the on-line mode or bypass mode as soon as possible.
MAINS LOAD
MAINTENANCE
BYPASS
UPS
Switch IA1