Diagnostics; Status And Error Displays - Siemens SIMATIC S7-1500 Manual

Diagnostics

7.1

Status and error displays

Introduction
Diagnostics by means of LED display is an initial tool for error localization. To further limit the
error, you usually evaluate the display of the CPU, the display of the module status in STEP 7
or the diagnostics buffer of the CPU. The buffer contains plain text information on the error
that has occurred. For example, you will find the number of the appropriate error OB there.
See also information on the status bytes: Address space and address assignment (Page 18)
LED display
The figure below shows the LED displays of the technology module TM NPU.
①
②
③
④
⑤
Figure 7-1
Technology Module TM NPU
Equipment Manual, 09/2020, A5E46384784-AA
RUN (green)
ERROR (red)
MAINT (yellow)
LINK (green)
PWR (green)
LED display on the technology module
7
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