Hi, 

I have a S7 1214c plc ( 6ES7214-1AG40-0XB0) with an additional input module sb1221 module (6ES7221-3BD30-0XB0).

When connected to the 24v and after doing a hardware download, the input module doens't seem to work.

Lights don't light up, not when applying 24v nor when enabling an input.

Am I missing something? Do I need to enable something additionally?

Thank you in advance.

Kind regards,

Willem

Hi!

In that case, it is very possible that the card is damaged. As far as I understand, the LEDs should indicate some status. Try to verify the power of the module.

Hi,

I tried a new DI input module, and tried a new hardware upload with your mentioned steps. Did not change a thing. No lights on the module. What does this mean, broken PLC? 

Kind regards,

Willem

Hi,

does the cpu itself show an error? Is there an entry in diagnostics buffer of the CPU? You can also upload the diagnostics buffer as .txt file.

Is the singal board recognized in the online diagnostics and if yes, are there any entries in the module diagnostics of the board directly?

Do you have a wiring diagram which shows how the SB is connected at the moment?

Meaning of status LED can be found here:

Status LEDs

-> Status LEDs on a signal board (SB)

SB 1221 200 kHz digital input specifications

-> Table: Wiring diagrams

regards

sancruz

alanTI

It is written in the manual, but in case you have missed it, the SB1221 uses NPN inputs, meaning you have to pull the input to M to activate it.

 Didn't know, thank you !