Siemens S5-135U/155U System Manual page 197

Controls and
The controls and indicators are arranged on the front plate of the CPU
Indicators
module:
Figure 5-7
System Manual
C79000-G8576-C199-06
CPUs, Memory Cards, Memory Submodules, Interface Submodules
CPU 928A
QVZ
ADF
ZYK
BASP
RUN
STOP
RESET
OVERALL
RESET
SI1
Front Plate of the CPU 928 -3UA21
Fault Indicator LEDs (red)
Receptacle for
User Memory Submodule
LED (green)
Mode Switch
LED (red)
Momentary-Contact Mode Switch
Interface Fault Indicator LED (red)
PG Interface, 15-Pin
Order Number and Version
Release Lever
Locking Pin
5-57