Centroid Community CNC Support Forum

Howdy, Been working on a old Comet VMC500 conversion and got to the tool changer part before I crashed
Two main problems:
First.. I set up the G28/G30 offset and orient positions to be in perfect alignment when the Carousel goes IN. I get zero speed and orient complete signals good. When trying a tool change the z axis moves to tool change height, orient completes, Carousel comes in and for a split second the Carousel in light (IN32) comes on. The moment that input turns green, the CarouselIN ouput goes to zero and in goes back to the Out position with input 31 back to green. I can force the Carousel to come out and input 32 stays green by shorting the Carousel out to source ( 115ac ) but thats the only way. This mill doesnt have two coils for in out air cylinder operation and cant be wired like the stock wiring diagrams show with two. When activated it goes in and when voltage goes away it goes back out. Do i need a differerent PLC to account for this one coil setup ?
Thanks

Maybe you need to wire a latching relay so that the two signals from the Oak create the one signal your tool changer needs. So the carousel in signal would lath the relay on to hold the carousel in and the carousel out signal would release the relay.

Or modify the PLC code which would probably be the easiest way and involves no wiring changes. I cant imagine the changes would be hard. Just change the part where it activates the carousel in output to set a memory bit, and where the carousel out output is set, clear the memory bit. Then just control your one output based on the state of that memory bit.

Other guys here have much more experience with those type of tool changers so may be able to offer a better solution.

It is a fairly simple PLC program change, more or less as ashesman outlines.

There is no compelling need for an intermediate memory flag; just SET and RST your single carousel-advance solenoid output at the appropriate times.

Thanks for replies. If i had time to learn the PLC mods it would be the quickest way but I have my hands full ( and brain ) just trying to keep up with everything else. Id pay to get the PLC modded but I can get the the latching relay Weds and wire it in easy. Probably cheaper than a PLC change

As a side note and since its related.. I can start to do a tool change until the carousel IN time out. And the tool counter updates the bin ok but I dont understand why the "<F7> ATC function found in the <F1> Setup menu from the main screen of the CNC
software or in the Tool Offset Library" does nothing.. I click on it and stick in a tool number other than shows loaded ( BIn1 tool 1) and it does nothing.

Guy

I could modify the PLC program for you. It would require you to type in some commands to compile it. You can keep your current PLC program as backup.

Not sure why F7 didnt work for you in tool setup. I used it the other day and it worked ok. Maybe an ATC reset is required or it was unhappy about something else. But usually a warning would be displayed.

I' d be happy to pay to get it modified before I order a relay. I can run any commands to install here. Attached is latest report. I just tried the F7 ATC again and it just goes back to main screen after i do a cycle start. Ive run the ATC init a millon times and think I have the bin,tool numbers correct but who knows.. I never see a ATC init complete message if their is suppose to be one

Guy

I will have a look at that PLC code tonight. No charge, all care no responsibility

Sounds great bud.. I did notice the report.txt file shows all but the first bin as 000 and Im guessing thats why the ATC button doesnt work. Not sure why though...

Bin 0 means that tool is currently in the spindle. Centroid has no concept of no tool in the spindle so be careful of that.

Yea I meant to say the bins say tool 000. I try to init each bin with that tool number but it never seems to really take them all except for the bin Im currently on when I rotate the the carousel with the aux 8/9 buttons. Im sure Im doing it wrong but Im brain dead at this point.