Terminals
ID Label
Element
Purpose
1
Protective conductor terminal for PSU module and housing.
2
Strain reliefs for connecting cables, with metal contact surface for
cable shields.
3
DC Line
Screw
terminals
System connection, 24 V input voltage
4
Monitor Output Relay
output
Standstill of one or both fans is signalled via LED and relay contact to
the exterior, and results in shutdown of output voltages (can be shut
down via jumper F-R of the PSU; then only relay signal and LED
indication).
5
Enable Power
supply
Input/
output
No voltage at the EN input results in shutdown of the PSU. Not more
than 7 EN inputs may be driven with one U
H
output (front terminal).
6
DC 24 V; 0.4 A Output
This output can be used to power the enable inputs of the U Periphery.
7
Ext.Batt. 3.4 V Sockets
Sockets for external 3.4 V backup voltage.
Caution
Observe the appropriate VDE specifications, especially
VDE 0100. The terminals at the front are suitable for a conductor
cross-section of up to 4 mm
2
, solid, or 2.5 mm
2
, flexible. Ensure
adequate strain relief of the connections.
15 V auxiliary submodule
You can add a 15 V auxiliary submodule to the 6ES5 955-3NA12
power supply unit (e.g. if you wish to use SINEC H1). The auxiliary
submodule produces a stabilized 15 V output voltage from the 24 V
output voltage. The auxiliary submodule is short-circuit protected.
The output voltage is monitored. If the voltage is too low, the green
"15/24 V o.k." LED on the front plate goes off. If the voltage is too
high, the output is short-circuited by a thyristor.
1 2
2
2
2
3
4
5
6
7
DC Line
5V DC
24V DC 0,4A
15V/24V
DC
Monitor Output
Battery
Enable
Power supply
24V DC
+
-
L+
M
Disconnect
before removing
power supply!
4
6ES5 955-3NA12 Power Supply Unit
System Manual
C79000-B8576-C199-03
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