S7-314c-2 pn/dp dig in/out

Hi all

I'm having issues with the Digital Inputs and Outputs. I have a Digital output that I am clearly switching on, I can see the output is TRUE when I switch on to monitor the channels, likewise I can switch it off and it goes to FALSE. If I measure the output directly coming out of the back of the module (I am looking at DO.2, so the third one which is on terminal 24) I get 0.8Vdc, regardless of whether or not I am TRUE or FALSE on that output bit? cAn anyone guide me as to why this might be the case and how I would go about enabling the module so I get a 24V Digital Output?

I have 24V on terminals 1, 21, 11, 31. I have 0V on terminals 10, 30, 20, 40.

As I look at the all the modules I have, including analogue IN/OUT's I have no LED's on, other that the CPU RUN and DC5V. However, all the analogue channels I have configured are working. I would've thought I should see an array of LED's on indicating channels are in use? If I connect a wire to one of the DIG IN channels and directly to 24V the LED for that channel goes green.

I am completely new to Siemens and come from an Allen-Bradley CompactLogix background.

Any help would be appreciated.

Thanks.

Is the output LED turning green when you make the output high, if not is the HW config set up correctly?

No, I do not see the LED when the output is high or low (True or False).

if you go to online view and then to hardware configuration. Is the output card showing error or OK state.
Any red errors on PLC?

And you have wired +24VDC to M+ and M- terminals

All green, no errors on PLC or output card

Also, I have wired 24V/0V as described in my original post:

24V on terminals 1, 21, 11, 31. I have 0V on terminals 10, 30, 20, 40.

You can force Q-addresses,
Or if you have empty PLC project (disable all calls on OB1,) you should be able monitor Q-address and also setting Q directly via animation table without force commands.

If you open hardwire configuration on online view, is the online view showing same than offline project view?

Ok, thanks for the suggestions. I have looked at my Main Routine [OB1] and I have a couple of networks. I have dragged each program block on the networks. When I go online and monitor the Main Routine [OB1] a number of the program blocks are good and highlight with the solid green line box. A few however are highlighted with a dotted blue box, this includes the routine that contains the Digital Output program. Could this have a potential to disable the 24V output?

if you write right to Q-outputs from animation table, are outputs working then.
If you open your FC/FB driving outputs and click online view. Is the block running or says block not loaded?

Ok, not sure what you mean by Animation table - I have written a Force table to a couple of the outputs and I get no LED lights.
With respect to the block running or not loaded - where would I find this information?
Also, I have noticed a little symbol to the top right of the routine window concerning call environments that is telling me none are set.

FYI I am running TIA Portal V13

bgtorque said:

With respect to the block running or not loaded - where would I find this information?

Click to expand...

If you put the command BEU (block end unconditional) as the first thing in OB1 nothing of the program will be executed
That way you know for sure that outputs arent being written by the program. Then you can use a VAT table to set the outputs.

bgtorque said:

Ok, not sure what you mean by Animation table - I have written a Force table to a couple of the outputs and I get no LED lights.
With respect to the block running or not loaded - where would I find this information?
Also, I have noticed a little symbol to the top right of the routine window concerning call environments that is telling me none are set.

FYI I am running TIA Portal V13

Click to expand...

Make VAT table (variable animation table) and insert Q0.0, Q0.1 or what outputs you have configured for output card.

Make VAT table (variable animation table) and insert Q0.0, Q0.1 or what outputs you have configured for output card.

Click to expand...

I'm curious where you get that "animation" from. it's just "Variable table" afaik

What Q addresses are you using and do they match the h/w config?

Yes, Q addresses match the H/W config. If I put a volt meter on the L+ and M terminals on the card I can see 24V. Everything, CPU and DIG IN/DIG OUT cards and ANA Out Cards have common PSU (common ground) supplied by a Simantic UPS.

Going to the watch table when I force DIG IN or DIG OUTS I get no errors, nor do I get any LED's on the back or 24V from any DIG OUT terminal