Hi,

We got a CPU314C from school and would like to test if everything is fine.

We connected 24VDC to the cpu and loaded our program in the CPU.

We noticed that the led's on the DI/DO module didn't light up according to our program.

None of the leds on the 2 modules work.

We can flash the led on the CPU and load our program.

By forcing the output's, the led's also won't light up.

Does every module needs to be powered separately in order to have the led's to work?

Thank you guys

hi dchartier,

Thank you for your reply.

Our address configuration is ok i think.

We don't have any cables wired to the modules right now. Only 24VDC on the plc.

In attachment see our address configuration. 

hi Reyntjensmi,

have a look to the following manual.

SIMATIC S7-300 CPU 31xC and CPU 31x: Technical specifications

in Chapter 8.7 you find a block diagram of the integrated digital I/Os:

As you can see, the module needs a M that the LEDs can ligth up.

Without any wiring on the modules the LEDs won´t work.

hope this helps,

regards,

Well my dear friend, If you only want to test the DI/DO you can do it by just adding a VAT table and monitor the DI/DO online.

there will be no need of wiring the i/o modules.

Just go to Monitor/Modify variables under PLC drop down list and create a vat table

Regards

ASP

Buenos dias, 

al tener esa cpu integrada, necesariamente tengo que usar esas direcciones de entrada y salida por defecto? no puedo usar las que comienzan desde 0,1,2 y asi, porque tengo el problema que en el plc fisicamente enciende la entrada, pero en el programa online no veo el cambio 

Hello Jhonnn_est

Jhonnn_est

Good morning,

Since I have that integrated CPU, do I necessarily have to use those default input and output addresses? I can't use the ones starting with 0, 1, 2, and so on, because I have the problem: the PLC physically turns on the input, but I don't see the change in the online program.

 Best Regards,

Wit_Moderator