Quick question about PLC testing

[JesperMP]

Input simulators for the Siemens S7-200 series:

For 212-221-222: 6ES7274-1XF00-0XA0

For 214-224:     6ES7274-1XH00-0XA0

For 215-216-226: 6ES7274-1XK00-0XA0

 

[Eric Nelson]

Don't Siemens have a simulator????? Just about everone else does.

I think they have an 'ASsimilator', as in 'You will be assimilated'...

beerchug

-Eric

 

[BobB]

I think they have an 'ASsimilator', as in 'You will be assimilated'...

Not by choice anyway.

 

[RMA]

Don't Siemens have a simulator????? Just about everone else does.

Yes they do, but it's lousy!

 

[Edgar]

Thanx
I appreciate your feedback. I would test it 'live' but I am dealing with chemicals and I do not want to contaminate them (Costly).
So if I understand I can just live the terminal block alone, change all my outputs to internal bits and go on. In this case I will have to check thoe internal bits throughout the ladder program to see if they are energized?

 

[BobB]

Yes Edgar. You can do it that way. By using internal bits as outputs you will not really turn anything on. The disadvantage is that you will have to look through your program to track the operation.

If you break your program down into "modules" it will be easier.

Another method is to use the outputs and disconnect the common from the output card. That way there is no voltage available to turn on relays etc. I have used this method before.

 

[Ron Beaufort]

Edgar,

no offense if this is too "basic" but you said you were new at this ... here’s one thing that hasn’t been mentioned yet ... or did I just miss it? ...

anyway ...

be ABSOLUTELY SURE that what you've documented in your program ACTUALLY corresponds with the appropriate real-world devices ... specifically, suppose that it looks like the PLC is turning on the “FILL valve” at output “Y” ... but what if the terminal screw for output “Y” has been incorrectly wired (oops!) and the “DRAIN valve” has been connected there instead ... your PLC program might execute fine on the screen ... and all of the logic might look great ... (look! see! there’s the FILL valve coming on just like we planned) ... but remember that the PLC doesn’t know diddly about what’s really wired up to the input and output screws ... so when SHOWTIME finally rolls around, all of a sudden it’s the DRAIN valve (not the FILL valve) that actuates in the field ...

again ... a very important step in commissioning any machine is to make absolutely sure that what you THINK you’re looking at on the screen is EXACTLY what the PLC is looking at in the real world ... especially if you’re going to be removing and then reconnecting the wiring for your field devices ...

and don't forget to register on the forum ...

 

[Edgar]

I found another way, which I should have though about earlier. This machine has only about 4 motor-pumps which are really the main concern, everything else should not affect anything. I just noticed that I had 5 spare outputs on my PLC so I changed the addresses of my motor contactors... to those spare outputs. And now I think that I should be able to test the system without forcing any inputs and at the same time tell if my motors are on or off by the LED's on the controller. What do you think?

 

[elevmike]

Very good Edger...

Now how about regestering and joining the club?

Welcome!

 

[Bitmore]

Welcome to the BEST place to vent your anguish! Traffic lights anyone?

 

[Eric Nelson]

Traffic lights anyone?

[attachment]

beerchug

-Eric

 

[Fred Raud]

i thought it was the elevator project for starters?

Fred Raud

 

[Fritz_frederix]

Hello,

Siemens has a simulator software PLCSIM.

Rudi

 

[Edgar]

I have a problem with this program. I have this pneumatic cylinder output that doesnt energized when it is supposed to. I checked it online and all the inputs are on but the output does not come on, not even for a second. Can somebody tell me if they know what's going on?

 

[elevmike]

Edger,

If you register and join the forum you'll be able to post your code so others can take a look at it.