One Shot Rising {OSR} Question

gappvembe

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Join Date
May 2007
Location
MI
Posts
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I've always been a bit confused with these {OSR}s.
What I wonder is, if I use one [as indicated on the picture] will it turn on the output briefly and shut it off.

What it is actually working is a solenoid; NON-spring return, so it stays in place until the opposite side is energized.


breakon-offosr.jpg
 
It will turn on for only one processor scan with any branches making it true. It must then see a false condition before it can be turn on again. typically I don't see it used much for firing outputs as your output will only turn on for one scan, (10-20ms) probably not long enough to fire a solenoid.
 
I would use a timer for something like that.

Why do you only want it on for a short time?
 
Typically you would energise the solinoid to cause motion and de-energize it when the sensor saw the motion carried out. Now am confused. OK what Im saying is for example, use an (OTE) or (OTL) to energize the solonoid. Then either make the (OTE) false or (OTU) when ever the sensor detects the action, IE: cylinder extended, pressure reached ETC... CLEAR as MUD yet.

Hopefully this will work because timers would be ugly.....

Bob
 
JOLTRON said:
I would use a timer for something like that.

Why do you only want it on for a short time?
Click to expand...
I mentioned before the output turns on a solenoid, an air solenoid in fact, and it will stay in that specific position until the the opposite solenoid is turned on.
Basically it is one of these with both ends having a "Black" part (the solenoid).

pp.mk8.gif
 
bobwithdana said:
Typically you would energise the solinoid to cause motion and de-energize it when the sensor saw the motion carried out. Now am confused. OK what Im saying is for example, use an (OTE) or (OTL) to energize the solonoid. Then either make the (OTE) false or (OTU) when ever the sensor detects the action, IE: cylinder extended, pressure reached ETC... CLEAR as MUD yet.

Hopefully this will work because timers would be ugly.....

Bob
Click to expand...
I get what you are saying, the thing is, there is no pressure. It extends one way and extracts the other. Full motion. That is it.

To be honest. The program works fine like it is, my boss just has a thing about having these neumatics on all the time, when they could be shut off and they stay in place.
 
Is there a prox to detect when the cylinder is extended or retracted. That would be used to turn it off.

Thanks Bob
 
Last edited:
What you are saying is that you are using a 3 way dual detented valve. Timers will work but unless you have sensors to detect when the valve is in either position you will have a tough time doing any type of fault diagnostic if the valve or solenoid fails.
 
bobwithdana said:
Yes exactly, and as said you dont want to leave it evergized. But on the other hand on for one scan is not good. So therefore the example above is the correct way to do the logic. Leave the sol energized as long as it take the motion to complete. OK?

Thanks Bob
Click to expand...
There was an issue this morning when the machine was initially turned on. The Output that fires the BRAKE OFF, the rung to turn on that output is whenever the BRAKE ON isn't made. So it was sitting for hours, with this solenoid on.
When the machine is working at full speed, they go on and off rather quickly for a while. It is when it is waiting for product (this is for a lane system), where the solenoid stays on for periods of time.
 
Here is what I came up with.
Basically after the brake on is done, then it has a second to activate the solenoid and it will stay in that state on its own.
It will be alright if the timer isn't finished by the time it's ready for the brake on again (I doubt this will happen, just because that would be too quick for this specific operation), because it can still do what it is supposed to.

brakespecifics.jpg


Brake.jpg


What do you think?
 
OkiePC said:
Most of those types of valves will tell you that they can handle 100% duty cycle, but experience tells me (and your boss) that you shouldn't push the device to its limit when you don't need to.

Paul
Click to expand...
That's the thing, this system has been implemented for over a year,and has worked fine! Now he's concerned.
0rolleyes.gif
0laugh3.gif
 

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