vmc4020 input/output error

[darth bayrinth]

Where i work, we have 2 fadal VMC4020 cnc machines. connected thru the rs232 plug is a network cable to a computer that has the Predator CNC program that allows the workers to create their programs and then send it out to the machines to be downloaded.
one of my 4020's works great(lets call him "bob"). Bob will pull the program in and run it. no problems.
the other, (lets call him "jim") nothing but problems. At random times, Jim will actually pull the program in from the predator and run the program. other times, jim wont.
We will have a fadal service guy come out and he will trouble shoot it, fiddle with some switches and programs, and then itll work. 2-3 weeks will pass and then the machine isnt working again.
the only things that change during the 2-3 week difference, is the machine gets turned off, and one of the workers will punch in his own program to make the machine do what it needs to do.
Now, i have watched the guys enter in their programs, to see if they hit a "memory dump" or "kill memory" button, but they dont. so the only thing that i can think of is that whenever the machine is powered down it looses some kind of setting, something deep inside that i dont know what it is, and i am totally stumped.

any help would be appreciated, even if it is the dreaded "ive had the same thing happen and it cost me a new machine" response...i hope not....

thanks

[Yamahamer]

Sounds like the Baudrate is getting changed in "Jim".
Does Predator CNC program have a auto decect? I use NC Fadal to talk to mine and have to auto detect each time I change machines to set Baudrate?

[darth bayrinth]

Sounds like the Baudrate is getting changed in "Jim".
Does Predator CNC program have a auto decect? I use NC Fadal to talk to mine and have to auto detect each time I change machines to set Baudrate?

the baudrate is constant. it is set at 9600 on the machine. on predator, it is also set at 9600. although, i wonder if maybe setting the predator baudrate to autodetect may work.

[Yamahamer]

I have a 40/20, 50/20 , and a 80/30 all set at 2400 and had the same problem until I started useing the auto detect? It never made sence but it works now. May be worth a try.