Pico Programming issue

[jjgulley]

I'm not sure if I can perform this function or not, but what I'm trying to accomplish is having the same input perform an on and off function. The input is a momentary contact from an outside source via a website. The operator can toggle the input to latch and activate a series of pumps. Float activation causes the pump activation to unlatch which in turn shuts off the pumps. The system is not allowed to run un-monitored, so if the operator has to leave the monitoring screen via his website, I would like that same activation input to then shut the pumps off. Ideality this could be done with a second input via the web site, but the unit we have only has three available remote outputs and they are all being utilized. Attached is the site file. The pump activation is on rungs 21 thru 25. Any help would be appreciated.

 

[jrwb4gbm]

I haven't any idea how you are generating a remote output but here is a couple of thoughts. With three outputs and some creative thinking maybe you could switch them off or on in a way to create or encode a binary combination of 0 thru 7 or 000 thru 111. Y ou could then decode it at the pico end. Another thought is to develop a watchdog rung that would require the input activation periodically. If the watchdog didn't receive the activation pulse then it could shut down the pumps.

 

[jjgulley]

We are using a SCADA style wireless Mission unit that has a web site the operators log into to monitor tank levels, alarms etc. The mission unit does not have enough capabilities to control the entire system. So the Pico unit runs the main systems and the Mission unit monitors the 4-20 level controls and misc alarm conditions. The mission unit has three remote capable outputs that we are using to activat two alarm conditions at the site throught the PICO unit and the pump activation mode of operation.

 

[Lancie1]

I would like that same activation input to then shut the pumps off.

It seems that you could use alternator (flip-flop) logic in your Pico program to use the single input to turn the pump activation on then off, alternating each time that input is activated.

I assume that the input on Rung 13 that is labeled "KO88 LSHH MISSION" is the one. Insert a rung above Rung 13, and program that rung to produce an alternating Marker bit "M07" when the K088 input goes on/off. Then change the address of the first instruction on Rung 13 from "KO88 LSHH MISSION" to "M07".

 

[jjgulley]

Marker bits 1,3,4 on rungs 18,19,20 can shut the pumps off, but those are alarm condition and will generally not be what is shutting the pumps off in a normal capacity. marker Bit #2 on Rung 7 Wet Well LSL is what will be shutting the pumps down under normal circumstances.

 

[Lancie1]

EDIT: Sorry, I have deleted my comments because I don't have enough infromation to solve this problem.

 

[Lancie1]

Marker Bit #2 on Rung 7 Wet Well LSL is what will be shutting the pumps down under normal circumstances.

..what I'm trying to accomplish is having the same input perform an on and off function. The input is a momentary contact from an outside source via a website. The operator can toggle the input to latch and activate a series of pumps.

Your two statements above seem to be contradictory. If I07 is the input that you want "the same input to perform on and off function" to shut the pumps down, then simply wire a 3-position switch in parallel/series with the LSL input, so that Position 1 = existing Wet Well LSL; Position 2 = Off, Position 3 = ON. See attached picture.

On the other hand, if it is an input from outside source via a website that turns the pumps ON, that is a different problem.