Riello UPS MASTER HE, User Manual

Page: 37 / 57

0MNMHEM30RUENUB 00 pag. 37 / 57
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UPS UPS
UPS UPS
B A
4.2 Electrical system set-up
All the information contained in the section on electrical system set-up in relation to the MASTER HE (page 12)
remains valid with the addition of the information set out below.
4.2.1 Input
The instructions seen in the first part of the manual for a single UPS remain valid; each unit must be protected with
equivalent fuses or switches.
4.2.2 Differential
In order to avoid unnecessary interventions, versions with several parallel-connected devices must have a single
differential switch inserted at the input of the whole system, as shown in figure B.
4.2.3 Emergency power off device (EPO)
When several devices are connected in parallel, the EPO command must be sent to all UPSs simultaneously, as
shown in the figure below:
a - EPO terminal board on the UPS
b- EPO switch with auxiliary contacts (not provided).
The button must have the same number of auxiliary contacts as the number of parallel UPSs. Each UPS must have
the jumper on the EPO terminals (page 19 ) removed and the wires from the auxiliary contact of the button must be
connected instead of the jumper.
The contact must be closed with the button in the rest position and be opened when the button is pressed.
The connection must be made with the UPSs switched off.
UPS 1
a
UPS 2
a
UPS 8
a
b