Siemens Simatic S7-1500 / ET 200MP - Page 48

Interrupts/diagnostic alarms
6.1 Status and error displays
Technology module TM FAST (6ES7554-1AA00-0AB0)
Equipment Manual, 04/2023, A5E52301130-AA
47
Channel LEDs
The CHm, DIm LEDs and the LEDs of the DIQm used as digital inputs indicate the current level
of the associated signals. The LEDs of digital outputs DQm and of DIQm used as digital
outputs indicate the desired state.
The flashing frequency of the channel LEDs is limited to approximately 24 Hz. If higher
frequencies are present, the channel LEDs do not indicate the current status but instead flash
at 24 Hz.
Table 6- 3 CHm/DIm/DQm/DIQm status displays
CHm/DIm/
DQm/DIQm
LEDs
Meaning Remedy
Off
Channel/digital input/digital output at 0
level
—
On
Channel/digital input/digital output at 1
level
—
On
(CHm/DQm/DIQm)
Diagnostic alarm:
e.g. Error at digital outputs
• Evaluate the diagnostic alarm.
• Check the wiring or the connected
load.