Siemens SIMATIC S7 - Page 122

Fail-Safe signal module (SM) diagnostics
6.2 Fault diagnostics
S7-1200 Functional Safety Manual
122 Manual, 02/2015, A5E03470344-AA
Description
DIAG LED
Input
Fault LED
Status LED
LED color
Green / red
Red
Green
Firmware update in
progress
Flashing green
Off
Off
- Off; - On; - Flashing (Flashing frequency: 2.0 Hz)
1
All channels passivated indicates a module-wide fault occurred. This could be an external condi-
tion such as supply voltage low or a detected internal module defect.
2
A single, dual color (green / red) flashing LED
3
Alternating flashing of the separate fault (red) and status (green) LEDs
Table 6- 3 Module DIAG and 1oo2 input channel LEDs
Description
DIAG LED
Primary input
Secondary input
Fault LED
Status LED
Fault LED
Status LED
LED color
Green / red
Red
Green
Red
Green
Input state 0
(equivalent)
On green
Off
Off
Off
Off
Input state 1
(equivalent)
On
On
Input state 0
(non-
equivalent)
Off On
Input state 1
(non-
equivalent)
On Off
Discrepancy
error
Flashing red
On
Off
On
Off
Discrepancy
error resolved;
awaiting
reintegration
TBD
1
Flashing red
and green
2
Flashing
2
Flashing
- Off; - On; - Flashing (Flashing frequency: 2.0 Hz)
1
A single, dual color (green / red) flashing LED
2
Alternating flashing of the separate fault (red) and status (green) LEDs