Ladder program

Hello, attached is a program i designed to control my simple power system. Please kindly go through it and help me out.

I have a busbar onto which 3 loads, 2 generators and a utility line are connected. i want to set my generation (utility power)to say 50MW when all the loads are on and the generators off. I want to increase the load (i used a counter) and calculate the frequency from
generation - demand= change in demand;
change in demand/14.0= change in frequency;
frequency= 50+change in frequency;

when the frequency goes below 49.5, generator 1 comes on and the generation increases by 7MW and the frequency settles. when gen 1 is on and the frequency gets below 49.5, gen 2 comes on and the generation increases by 7MW. if the same continues, the loads 1 and 2 go off. the reverse should happen incase the frequency gets above 50.5.

this is a kind of automatic load shedding depending on frequency only that i will have to load shed after having all my generator on.

Please guys, try and look through my failed program and help me for adjustments.

what could be the best way of increasing demand and also for generation?

if anyone has done something similar, feel free to share it with me. i am sure it will be of great help.

thanks in advance

Nobody has answered you because you forgot to attach the ladder file.
Also 50MW is scary ;-)

gbradley said:

Nobody has answered you because you forgot to attach the ladder file.
Also 50MW is scary ;-)

Click to expand...

He has a duplicate post with the file.

http://www.plctalk.net/qanda/showpost.php?p=421017&postcount=1