multiple vacuum valve control vi

[BLongworth]

Hi,

First post here, seems like a simple one, but I haven't found a good answer yet, so here goes.

I'm writing a vi to control a vacuum system with about 20 valves and 10 gauges, and I've been trying to figure out a somewhat neat way to check valve states, user input and open/close the valves without having little case structures for every valve. It's the same basic command for every valve, just with different address information. I'd also like to figure out how to send commands to the valve only when it's state needs to change. To this end I've been playing with event structures, but it seems like I'll need a case for every valve transition.

No need to code anything up, just some hints or directions to look into would be really helpful.

TIA,

-Brett

[Tom Limerkens]

Just an idea,

Maybe you can combine the LVOOP with XControls, so you can put your 'per valve/gauge'

user interaction intelligence in the XControl,

and keep the data in LVOOP objects.

Don't have much experience in the LVOOP yet, bute sure there are some wireworkers

who can point you in the right direction

Tom

[Syd Chasm]

Just an idea,

Maybe you can combine the LVOOP with XControls, so you can put your 'per valve/gauge'

user interaction intelligence in the XControl,

and keep the data in LVOOP objects.

Don't have much experience in the LVOOP yet, bute sure there are some wireworkers

who can point you in the right direction

Tom

Yep, I'd do the same. Create an instance of a class for each valve, with methods for valve open and valve close, and properties of "valve open" and "valve closed". I've done a similar thing before - the only added complication being that some of my valves were normally open and some were normally closed, so I had to have a different class for each valve type. My valves had limit switches, so I could easily tell when they were open and when they were closed, and a transition time of about 2 seconds to go from one state to another so I could build in a time-out error in the method so that if it took longer than 4 secs from commanding a change of state to the limit switch confirming the action, I could report an error. If you have gauges downstream of each valve, you may be able to use a change in pressure to detect valve failure (I'm guessing that there is a venturi downstream of each valve, and a gauge measuring the vac pressure?).

Syd