Need Help!- Bridgeport Interact 720 memory problem!

[FLjoyride]

I have a memory problem every time I turn on the machine I get program 0 erased error message, and it can't hold any program that I upload. I am thinking its because I used a cheap 24v power supply as a replacement and after looking at the specs, I remember the 24V DC power supply needing to carry a signal. The original one is a coutant model HSH6OU and I can't find them, the one I put in as a replacement worked for a week before this problem started, but I think it might be the reason my memory is not working. any help would be appreciated on either a replacement power supply or with the memory problem.

Heidenhain TNC2500 controls

Fanuc drives

A little History

Bought this machine used and set it up in a new shop. Got the power requirements sorted out and managed to get everything working after replacing one of the 24v power supplies. After two weeks of making parts at night, I went to turn it on after a long weekend. The machine tried to home itself off the ways, luckily the tool collided with the vice and I stopped it before it went down too far. I couldn't get the Z axis off the vice so I unbolted the motor and spun it 360 degrees lifting the Z axis 4 inches. I turned the machine back on and it started doing the same thing, trying to home into the table. I had to turn the Z motor again. I called rick at heidenhain and we went through resetting the machines internal limits. After restarting it several times and getting the home positions fixed, it started giving me the proram 0 erased problem. It would not hold any programs, not even the tool library program. So - after hours of troubleshooting Rick and I determined that there was a short between earth ground and logic ground, causing interference with the signal that is carried along the 24VDC power supply. We tracked it down from the controls to somewhere else in the system, but thats as far as we got. Now - months later, I have relocated to a more affordable shop and want to get this thing going again. It has the usual program 0 erased problem with the addition of a 'ext relaydc voltage missing' problem. Before the relay problem I could operate the machine manually without the memory. Sortof lost, going to replace the power supply to a solid state style one and go from there.

[gus]

that is a weird one.

the external voltage error could be a limit switch or any number of things in the emo string

If Rick says it is a ground short, find the damn short

Odds are it worked before the original power supply quit, so maybe a new one is in order.

Perhaps it needs to be hooked up differently, or needs to be isolated where this one isn't

[machintek]

I find it odd that the parameters are not lost but the program is.
I believe this machine has 2 24 VDC power supplies. One for the relays and such and one dedicated to the control. So swap them and see if your problem goes away.

George

[FLjoyride]

OK I got new FEAS power supplies with <2mv of interference. After finding the specs it looks like I needed at least <3mv and the cheap one I got was <120mv! I installed them tonight and I still get the program 0 erased problem on startup. After creating a couple bogus programs the machine pulled an error message, 'processor check error 2" Which I think has to do with the RAM memory if I'm not mistaken. Is there anything else that could be causing this besides the dirty power supply? Maybe all the interference fried the RAM? Need help on this one I'm not ready to send in the board yet.

[FLjoyride]

I measured the voltage between the case of the control power supply (the multi voltage one) and it is 12v from + to ground and -12v from - to ground?? This doesn't seem right, but if I measure between the two there is 24V, and if I measure to the control board mount hardware for the ground it is 24v as well. Seeems strange.

[gus]

First, if Rick dunno, we are all guessin

Second, I don't know what the multi voltage one is

you will not find people with intimate knowledge of the machine in front of you, so you need to explain better

Keep looking at power.

I know a ground loop in an old [heidenhain] machine of mine drove me nuts for a long time