Siemens S5-135U/155U - Manual (Page 93)

4-27
System Manual
C79000-G8576-C199-06
The following applies to input EN (Enable Power Supply):
S
Input EN monitors the voltage for < 3.6 V; it enables the output voltage at
3.2 V.
S
If two or more units are to be controlled jointly, connect input EN of the
PSU in the central controller to the EN inputs of the PSUs in the
expansion unit. Connect the auxiliary voltage U
H
, for example, to these
inputs. In the event of failure of the PSU in the central controller, all units
will then be switched off with the appropriate jumper settings.
Not more than 7 EN inputs may be connected to one U
H
output (front
terminal).
The following applies to selecting the cables for the terminals:
Terminals Cabling Max. Permissible Conductor Cross-Sections
Power supply
AC line
DC line
Phase L 1
Neutral N
Protective cond. PE
Positive L +
Chassis 0 V M
Protective cond. PE
4 mm 2 solid or 2.5 mm 2 flexible
4 mm 2 solid or 2.5 mm 2 flexible
4 mm 2 solid or 2.5 mm 2 flexible
4 mm 2 solid or 2.5 mm 2 flexible
4 mm 2 solid or 2.5 mm 2 flexible
4 mm 2 solid or 2.5 mm 2 flexible
Load voltage input (Voltage
monitor, Ext. 24 V DC) 24 V input (may be omitted if jumper
BA-EX is closed) 4 mm 2 solid or 2.5 mm 2 flexible
Enable power supply Set jumper from EN-U
H
or apply
w 3.2 V voltage at EN, with respect
to output chassis ground
4 mm 2 solid or 2.5 mm 2 flexible
Relay terminals, also
suitable to 230 V AC / 3 A 4 mm 2 solid or 2.5 mm 2 flexible
Monitor output for 24 V 4 mm 2 solid or 2.5 mm 2 flexible
Note
A voltage of more than 50 V must not develop between the output voltages
and the protective conductor potential.
Setting up the
Control Input for
the Power Supply
Establishing the
Cables
Central Controllers and Expansion Units Power Supply Units