G
AMATRONIC
E
LECTRONIC
I
NDUSTRIES
L
TD
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MegaV2 250 Installation Guide, Release 2.2
7
1.2.4.2
Neutral Line
During both installation and operation of the
MegaV2 250
, a neutral line must always be
connected to the UPS. This neutral line must be connected at all times while the UPS is working
and should not be disconnected at any time.
Caution:
If at any time the neutral line becomes disconnected, there will be no input or output
reference voltage because the input neutral line and the output neutral line are physically linked
together. This may result in the system defining its own reference voltage, which will be set by the
load distribution between the three phases.
This may cause serious damage to the UPS.
Caution: A 4-pole switching system can disconnect the neutral line.
Warning:
If you have a
four-pole
mains-to-generator
switching system, you are in danger of
having the
neutral line disconnected
when the four-pole switch is operated. This can result in
the problems described above.
To avoid these problems, we strongly recommend that if you use a four-pole mains-to-generator
switching system, you install an isolation transformer that constantly provides a neutral line to the
UPS.
1.2.4.3
Ac input and output connections
WARNING! RISK OF ELECTRICAL SHOCK OR INJURY! INSTALLATION
MAY BE PERFORMED BY QUALIFIED TECHNICIAN ONLY!
WARNING!
HIGH TOUCH CURRENT!
EARTH CONNECTION ESSENTIAL
BEFORE CONNECTING SUPPLY.
Before connecting the main input and output cables to the
MegaV2 250
main terminals, verify
that the circuit breakers on the feed board are in the OFF position.
Connect the rectifier ac input, bypass ac input, and ac output cables to the
MegaV2 250
.
Refer to Figure 4 or Figure 5 (connection diagrams), Table 3 (maximum input currents), Table 4
(recommended circuit breaker ratings), and to Figure 7 (the UPS’s terminal layout).
