page 66 / 84 0MLMHTM30RUENUA
The auxiliary contacts of SWOUT EXT and SWMB EXT must be connected to terminal J1 on the board 9AB2145 (aux
signals insulation). The purpose of this board is to galvanically isolate the internal circuits of UPS, so that, in case of
parallel of UPS, one auxiliary contact of the external switch is sufficient to be acquired by all the UPS in parallel.
For safe removal, the UPS must placed onto bypass, closing SWMB EXT, opening SWIN EXT and SWOUT EXT and
disconnecting the UPS.
Aux Contact SWOUT EXT must be N.O. as the power contacts while aux contacts SWMB EXT must be N.C., in the
opposite position of power contacts.
Note:
300kVA÷500kVA: Auxiliary switch of SWMB EXT opens
simultaneously
when closing power contacts
400kVA/500kVA: Auxiliary switch of SWOUT EXT opens
simultaneously
when opening power contacts
300kVA only: Auxiliary switch of SWOUT EXT opens
in advance
when opening power contacts
7.3
Mains, and load connections.
All the information contained in the section “Mains, load and battery connections” (page 28) in relation to the UPS
remains valid with the addition of the information set out below.
7.3.1 UPS AC input / output power connection
Refer to the Electrical Connections (Section 5) of this manual for information on how to size the cables for
each UPS
.
Parallel connect the UPS as follows:
- Connect the mains power supply phases L1, L2, L3, N to the
corresponding
input phases of each UPS L1, L2, L3, and
N.
- Connect the load phases L1, L2, L3, N to the
corresponding
output phases of each UPS L1, L2, L3, and N.
The figure shows an example of three units connected in parallel.
A)
Mains power supply line
B)
UPS input terminals
C)
UPS output terminals
D)
Load
(a1, a2, a3, c1, c2, c3) length of cables (see below)
Length of cables rule of thumb
The sum of the lengths of the mains power supply and output cables must be the same for all units. With
reference to the above drawing, these must be: a1+c1 = a2+c2 = a3+c3
a = length of input line cables
c = length of output line cables
OUT (C)
MAINS (A)
a2
c3
IN (B)
IN (B)
OUT (C)
a1
a3
2
c1
3
IN (B)
1
D
OUT (C)
c2
UPS 1
UPS 2
UPS 3
