Siemens S5-135U/155U System Manual page 521

Connector assignments of the power supply units
Connector X1
The terminals for the supply lines between the power supply unit and the
backplane are in an 8-way connector (Connector X1) at the rear of the unit.
The following figures show the connector assignments.
5V/18A power supply units
Pins 4 to 6 are not fitted.
5V/40A power supply units
Connector X2
The signal terminals of the power supply unit are in a 37-way connector
(Connector X2) at the rear of the unit.
The following figure shows the connector assignments. Pins 8 and 9 are
reserved.
System Manual
C79000-G8576-C199-06
M2 (0V)
1 2 3 4 5 6
M2 (0V)
1 2 3 4 5 6
GEP
RESETA
DSI
reserved
NAU
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
BASPA BAU
U-BATT
RESET
20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
Connector Assignments
5V/18A
7 8
5V/40A
7 8
+15V 24V
M2 (0V)
11-9