Are there free relay logic editors?

[OkiePC]

When I went to maint. tech school years ago, we had some software called "Pneu-Sim". It was pneumatic/hydraulic simulation with accompanying electrical circuits. You could design and test things with it, that nicely simulated real world results. It would even let you animate and adjust pressure regulators and flow control valves, display forces and speeds of actuators, and much more. You could dig into properties of objects to really fine tune the behavior of the simulated equipment and make it match real devices.

It was easy to do simple stuff for education but powerful enough to design and test ideas with.

I think it was dos-based, but very easy to use with a nice GUI including mouse support.

You drew the fluid power circuit with symbols and lines and could edit the properties of the devices and the plumbing, and alongside it was the electrical circuit.

Both were animated nicely when in test mode.

I googled pneusim and found some hits on rapidshare. I have no idea if that software owned by the school was expensive or shareware....I suspect it was not free...

EDIT: Well it looks like they have evolved PneuSim into this:
http://www.automationstudio.com/EDUC/en/product/Overview.htm

 

[ndzied1]

EDIT: Well it looks like they have evolved PneuSim into this:
http://www.automationstudio.com/EDUC/en/product/Overview.htm

Better get out your bigger wallet for that one. Very powerful and priced accordingly.

 

[Peter Nachtwey]

We use the PCSchematic software for electrical, pneu, and hy diagramming.
There is a free version:
http://www.pcschematic.com/english/index.htm
The free version is limited to 10 pages, 40 symbols, 200 connection points. This ought to be enough to make simple diagrams like the one shown.

For forum purposes that is all that is required.

OK, I was looking at S4 as a manual OR overide switch and then saw that if R4 was energised then C4 would never pull in.

If looks OK to me. If S4 is switched to the up position then R5 is NC and R4 is closed and the system will retract or go up which is what is desired.

One thing to get across to your "student" is that this design is potentially dangerous; if there is a fault to ground (and the 0v leg of the power supply is NOT isolated) in one of the cables out to the limit switches (which would not blow the fuse) then the Estop would not work as the return path through either R3 contact would allow R1/R2 to stay energised.

Also if R1 or R2 jammed, the stop would not work until the end of the stroke.

Good points. I was thinking of a more simple will it work stand point. Not whether it is perfect or complete.

I suspect it would be good to actually ask him/her to think what would happen if the wire out to the limit was damaged and make them think?

They aren't students. I am amazed to even see this on a hydraulic forum. In the past these were all "electric thingies". So far there is only the person that made the relay ladder and me that seem to know what they are looking at.

I will look at the other suggestions for free software. Free software is best because everyone has access to it and can play a long try what they see.
This isn't for me or my forum. I am just trying to make things easier on the H&P hydraulic forum. Not mine. We can do all of this easily within our motion controller.

 

[ivo.maenen]

When I went to maint. tech school years ago, we had some software called "Pneu-Sim". It was pneumatic/hydraulic simulation with accompanying electrical circuits. You could design and test things with it, that nicely simulated real world results. It would even let you animate and adjust pressure regulators and flow control valves, display forces and speeds of actuators, and much more. You could dig into properties of objects to really fine tune the behavior of the simulated equipment and make it match real devices.

It was easy to do simple stuff for education but powerful enough to design and test ideas with.

I think it was dos-based, but very easy to use with a nice GUI including mouse support.

You drew the fluid power circuit with symbols and lines and could edit the properties of the devices and the plumbing, and alongside it was the electrical circuit.

Both were animated nicely when in test mode.

I googled pneusim and found some hits on rapidshare. I have no idea if that software owned by the school was expensive or shareware....I suspect it was not free...

EDIT: Well it looks like they have evolved PneuSim into this:
http://www.automationstudio.com/EDUC/en/product/Overview.htm

A free english demo version of software like pneusim:

http://www.fluidsim.de/fluidsim/index4_e.htm