Timer as input and output

[amhd90]

Hello everyone,
I have this exercise to solve, and I tried it with RSLogix micro and work but not as I want.
The exercise say:

When start button ST1 is pressed and the level sensor of the boiler LS1 is off, a switch S2, conducting electricity for a lighter to give flame to the oven and a timer T1 is on for 30 seconds.
After this time, S2 (of the flame) should be off, the switch S1 is on to open valves and let petroleum fluids get in the boiler.
When LS1 is on, pump controlled by S1 should be closed.

Is this ladder (see images) is good enough or my process is working wrong ? The timer starts on stop button not on the start one. I tested with RSLogix micro and it tells me that the start button bit is always "1" with a red rectangle on it.

 

[amhd90]

Okay so no one has an answer and users are playing the testing game. what a site. ha

 

[jvdcande]

In the image I see that the Flame Seal output is forced OFF. This way, whatever you do, it wont work...

PS don't be ****ed off if not everybody is there when you expect them to be. We all have a life besides PLC as well.

 

[amhd90]

I am just angry of TESTINg threads that says: Testing and some replay without something useful, i thing admin should be more effective deleting those posts. And thank you for your help.

 

[danatomega]

Yes, if you're going to be pi$$ed off, then go away - no-one is getting paid to do this!

But more to the subject, you have the output in the program twice.
That is not good, remove the output from the first rung since it's being controlled properly in the second rung.

I'm unsure how pressing the stop button is making the timer run unless the start button is N.C. (maybe the red rectangle indicates this) and the stop button is N.C. also?

I don't have any experience with RSlogix Micro.

The first rung appears to use the timer ENable bit to seal in the rung but you probably need the .DN bit to un-seal the rung (or maybe not, it's your logic problem to solve, after all).

"Testing thread" ... I have not seen anything like that on this forum (and I've been here awhile). Not nice to come to a forum and get snippy if no-one responds!

 

[jrwb4gbm]

Okay so no one has an answer and users are playing the testing game. what a site. ha

Perhaps it is a language issue but the post included in the above quote appears a bit rude. Please see the info in the link below.
http://www.plcs.net/rules.htm

 

[rdrast]

Another added to the block list.

 

[amhd90]

Another added to the block list.

Block as you wish

 

[D.Chris]

Bro, the "test" posts are in the practice sub-forum. Its purpose is to test posting picture uploads, rungs, etc. That's why there are no replies or discussions, nobody is asking anything over there.

As for your problem, you need to make sure the normal status of both PB. Just like @dana said, most likely both PB have normally closed contact. If that's the case, you'll need to alter the logic a little bit. And you might need to unlatch the first rung after 30s is over, otherwise the lighter will stay on even after the timer elapsed.