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34007724EN/AA
UPS with separate Normal and Bypass AC inputs
Main low-
voltage
switchboard
(MLVS)
load
Bypass AC
Normal AC
2. Installation
2.5 Installation depending on the system earthing arrangement
(SEA)
UPS with common Normal and Bypass AC inputs
Change in SEA between upstream and downstream or galvanic isolation required
load
Bypass AC
Normal AC
Main low-
voltage
switchboard
(MLVS)
Main low-
voltage
switchboard
(MLVS)
load
Bypass AC
Normal AC
Change in SEA between upstream and downstream or galvanic isolation required
Main low-
voltage
switchboard
(MLVS)
load
Bypass AC
Normal AC
(*)
(*)
(*): The transformer is not necessary if:
◗
Normal and Bypass AC inputs are connected to the same source,
◗
and wires cross sections and wires lengths on Normal and Bypass inputs are identical,
◗
and upstream protection is provided by only one switch with RCD (residual current device) for Normal and Bypass inputs.
8
10
11
8
10
11
11
10
8
11
10
8
Comet EX must be fed from a 3-phase source with neutral.
