Timing Sequence

[Guest steveyti]

I am very new to PLC's in general and I have just recently completed the tedious task of creating my ladder diagrams from my boolean expressions. This would include coils that have contacts inside of the program based on 8 Inputs all N/O, only 4 of which are momentary. There are 4 outputs and 3 "modes" of operation which I have created a ladder to select mode ... this closes the proper contact in the program to continue with that particular mode. The outputs are relays that connect the line voltage to solenoids however there must be a standard delay time before these valves open. I am interested in the process of mapping the I/O slots on the I/O modules to 1) momentary and non momentary contact type inputs 2) close the contact to allow voltage through to a relay coil 3) how a delay would work for output I looked through the example programs by chackorules but have only downloaded them I am not sure if they are too eloquent for such a simple design! What I have done up until now is to just label the contacts the same as the coil. I have not gotten to outputs yet. For inputs I would label the contacts with a name and for the address i have used %I and it has auto addressed to %I00001 my confusion arises when I look at my module and see addressable memory starting at %I0001 if anyone could point me to a good site explaining the I/O and anothe explaining output timing that would be great. Meanwhile I will continue to dig through this huge user manual. I should explain that I am using versapro 2 and that I am using a GE Fanuc 90-30 Edited November 2, 2004 by steveyti

[Guest steveyti]

So now I have found the %M used in the downloadable examples and also examples of timers. Still interested in hearing about output delays.

[Wordman]

I don't want to throw you off path since I've never programmed in this PLC family before, but every single family i have, had simple timers or counters. You should be able to use a N/C contact from a timer enabled function. Once it is complete the N/C will open. So put the N/C before your output coil. And momentary inputs will be on momentarily, so if you need them to stay on, you have to latch it by using a parallel N/O contact from your output coil. And you can reset it using a N/C in series of those two. These are all basic PLC concepts