04-3275_OPM_ABB_CONCEPTPOWER_DPA_500kW_EN_REV-A.docx Page 51/78 ABB
Modifications reserved
POSITION OF IA1
EFFECT
ON
Bypass-Switch Closed (Load supplied directly from mains)
LCD-indication: “MANUAL BYP IS CLOSED” LED Indicators will indicate as shown in
Bypass-Switch Open – Normal operating condition (Load supplied by inverter)
LCD-indication “MANUAL BYP IS OPEN”
LED Indicators will indicate as shown in table below.
NOTE!
ON OPERATION MODE “MANUAL BYPASS“ THE LOAD IS NOT
PROTECTED AGAINST ANY MAINS FAILURES OR MAINS
DISTURBANCES.
6.6.4 Output Switch/Parallel Isolator (IA2)
Every UPS-unit is provided with an output parallel isolator (IA2) which, when opened isolates the corresponding
unit from the PARALLEL BUS and from the LOAD. Once IA2 is open there is no power on the load coming from the
UPS.
In redundant parallel configurations it is used to isolate a unit from the parallel system without the need of
transferring the load to bypass.
POSITION EFFECT
Normal Operation (Load supplied by UPS)
OFF
UPS isolated from Parallel Bus for maintenance or UPS replacement (UPS not supplying
load)