Engineer83
Member
Hello,
I have looked through some of the posts on traffic signals. I see they are a sore topic for homework assignments. However, this one is a real life issue at a construction site that I am on right now. We have a long single lane access drive which we want to control the traffic with (2) Red/Green Traffic Lights. We purchased a micro PLC hoping to utilize a simple program to control the lights.
We are going to pull a Hot to each lamp. Each lamp will be connected to a relay output on the controller. We want a 20 Sec - Red/Red, a 60 Sec Green/Red, 20 Sec Red/RED, and 60 Sec Red/Green sequence. We just want this to loop. If the power goes out, I want to press a function key to begin the sequence though. I also put in a status screen to show which lights are active. The bulbs are linked to the relay outputs.
I attached my attempt at this. I want to warn you guys it is rough at best because I design feeders and branch circuits otherwise (haha). It is my first attempt at PLCs in quite awhile. I used cascading timers to try to get the sequence. I am wondering if the expert PLC programmers have any thoughts on this attempt.
Your help would be greatly appreciated.
I have looked through some of the posts on traffic signals. I see they are a sore topic for homework assignments. However, this one is a real life issue at a construction site that I am on right now. We have a long single lane access drive which we want to control the traffic with (2) Red/Green Traffic Lights. We purchased a micro PLC hoping to utilize a simple program to control the lights.
We are going to pull a Hot to each lamp. Each lamp will be connected to a relay output on the controller. We want a 20 Sec - Red/Red, a 60 Sec Green/Red, 20 Sec Red/RED, and 60 Sec Red/Green sequence. We just want this to loop. If the power goes out, I want to press a function key to begin the sequence though. I also put in a status screen to show which lights are active. The bulbs are linked to the relay outputs.
I attached my attempt at this. I want to warn you guys it is rough at best because I design feeders and branch circuits otherwise (haha). It is my first attempt at PLCs in quite awhile. I used cascading timers to try to get the sequence. I am wondering if the expert PLC programmers have any thoughts on this attempt.
Your help would be greatly appreciated.