ATC - Schematic/Operation Question

[RJS100]

I am getting ready to bench test a carousel ATC that I built with the goal of being compatible with the stock Centroid ATC schematic and programming created by the CNC12 Wizard. I just noticed that I overlooked a small detail.

In the attached Centroid schematic, one output is used to activate a solenoid to move the carousel out. A second output is used to open a second solenoid to move the carousel in.

My ATC uses a multiport valve so that when the solenoid is activated, the carousel will move out. Once power is removed from this solenoid, the carousel will instantly move back in.

If I use the attached schematic, and use only the "CarouselOut" output to activate my multiport solenoid, can I simply disregard the "CarouselIn" output?

Thanks... Richard

[cnckeith]

hi can you post some photos of the atc and machine tool?

[RJS100]

Hello Keith,

Attached are drawings of the ATC and ATC + Benchtop mill. Both images show the carousel in the carousel-Out position as if the "CarouselsOut" solenoid is activated. Do you think this will work if I only use the "CarouselIn" output?

Once I put it together again, I will post actual pics.

Richard

[cncsnw]

Both images show the carousel in the carousel-in position as if the "CarouselsOut" solenoid is not activated. Do you think this will work since I am not using the "CarouselsIn" output?

This is a good illustration of why "in" and "out" are not a good choice to describe the movement of a machine part. Some people think "out" means "out of its parked position", and other people think "out" means "out of the way". Fluid power people generally use "out" to mean "the rod is out of the cylinder body".

Historically, Centroid uses "carousel in" to mean "advanced toward the spindle", and "carousel out" to mean "retracted to the park position".

Historically, Centroid PLC programs have been written to assume a two-coil, detented solenoid valve: one that retains its position after coil power is turned off, until the other coil is turned on to shift the valve back.

Switching to a single-coil valve -- on to advance the carousel, off to retract the carousel -- is one of the most commonly-needed PLC modifications.

[RJS100]

Thanks for the nice explanation. I have never seen a double coil solenoid valve, so this is all new to me. I failed to notice the double outputs on the schematic until I had mounted the solenoid and started wiring it.

At this point, I would really prefer keeping as is. While I planned on making this work with stock PLC, this is a bit of surprise. Two thougths:

1. Can you give me an idea as to what a custom PLC would cost. Feel free to PM me or email richardsalzman@hotmail.com
2. Is the attached solenoid valve an example of what you were thinking?

Thanks.... Richard

[cncsnw]

Probably. I would opt for one from a manufacturer who can spell, and who can draw a legible porting diagram; but then I am just an elitist snob about such things.
https://www.automationdirect.com/adc/sh ... s-5222-24d

[suntravel]

Probably. I would opt for one from a manufacturer who can spell, and who can draw a legible porting diagram; but then I am just an elitist snob about such things.
https://www.automationdirect.com/adc/sh ... s-5222-24d

Since I am German I would prefer Festo for 5/2 valves

Uwe

[RJS100]

Wow. Thanks for your suggestions on valves. I actually ordered on from Automation direct AVS-5221-24D and then realized that is over 6 inches long. It won't fit where it needs to live

My solution is to wire a self-latching relay to force the single solenoid valve to act like a double solenoid valve. This should work as long as the CNC12 logic does not activate CarouselIN and CarouselOUT simultaneously. Based upon Marc's explanation...I can't imagine why this would ever happen.

Richard