Good day Experts,

I am new and currently working on S7-1200 PLC/control.

I have one (1) CPU- 214C DC/DC/DC, and three (3) signal modules SM 1223 DI 16\DQ 16 x 24VDC. Right now, I am able to configure it via TIA portal v17 and all outputs are connected to 24 VDC relay coil. But when I try to switch one of the outputs there is no 24VDC present but the modules output indicator are illuminating.

Can someone help me with this one

thank you and regards,

Marl

Hello Marl;

What is he exact part number of your SM 223 DI/DQ module? As you can see in the screenshot below (taken from the Siemens Industry Mall, Siemens' electronic catalog for automation equipment), there are various models, distinguished by the number of input/outputs, and by the sink or source connectivity.

In case these last terms are not familiar, have a look at this document that should clarify this concept:

- What is the meaning of the terms "sinking" (German: "P-lesend") and "sourcing" (German: "M-lesend") in digital modules of SIMATIC?

https://support.industry.siemens.com/cs/ww/en/view/23451499

With the part number of the SM module we should be able to provide a wiring guide that might help you out.

Hope this helps,

Daniel Chartier

0_Einstein

Perhaps you could post a screenshot of the schematics for the DQ module which shows the L+/M of the module and it's fuse(s) or circuit breaker(s) feed into the DQ module?

It is a delight to 'hear' your 'voice' again. Welcome back.

Because there is mention of 3 cards, I am thinking that the electrical circuit design would be okay. I am more focussed on suggesting that the connections be measured with a hand-meter for the voltage. 

I cannot say how many times my team have made some error with the bridge pieces that interconnect the (-) terminals. The M pin on the card is just simply floating in those occasions.

Hopefully it is not a CPU1212 that is mistaken for a CPU1214.

I would even go as far as suggesting that the cards be swapped with each other to see if the problem follows the card. This is easy to do because the terminal strip can be removed from the card -- as you know.

~