ydac underflow error

[dreammstr6]

on a bridgeport eztrak dx with a bmdc3l when it tries to home i get the y dac underflow error. but it does move to the home switches. but will not run. i have tested the bmdc3l card and it passes all tests. i put the card in a working machine and the machine just barely bumps the drives then shuts off saying drives not on.

[dreammstr6]

one strange thing is when it loads into eztrak the arrow key selections are missing and the selection 4 and 6 is missing any thoughts?

[machintek]

A DAC UNDERFLOW occurs when a axis moves without the control asking it to.

A DAC OVERFLOW occurs when the control commands a move but does not see it.

A display that is missing things is indicative of corrupted software.

George

[dreammstr6]

thanks for the info. i do have one question. my personal eztrak sx mill is running a bmdc2 card. i tried the bmdc3l out of the eztrak dx in it and i got the same result. does the dx use different software for the bmdc3l? they had the sme softwre that's in mine. they purchased install disk from emi. looks to me that they ordered softwre for sx.

[machintek]

I used to use certain versions of software for certain age machines. Some very early EZTRAKs used mother boards with a 286, then a 386 processor. These can be a bit sensitive to the software versions. Usually I do not go above version 3.02. The BMDC version does not matter. What matters is that the BMDC software matches the machine software and parameter version.
I could use version 5, 6 or 7 with the DX controls.

George

[dreammstr6]

thanks again for the reply. if that's the case then i guess the machine has bmdc issues even though it passes the b3t.exe tests. because the software in my mill is working properly and it will not function with the bmdc3l card out of the other mill. i have even tried a fresh install of eztrak on the dx machine and same result. i guess when it loads bmdc.bin something is getting lost. it tries to home and all but some of the choices especially 4 and 6 are empty any other suggestion to try on this machine? i figured if it would pass the b3t.exe test and load ez trak it should work but not that lucky

[machintek]

The B3T test is not a absolute. Just as SCANDISK will not find all errors.
I was just called to a EZPATH that kept giving a error that the X limits were exceeded. I wrote a test program but in view it went off the screen giving the same alarm. Pressing the - key in the run mode you can see the program translation (from conversational to G and M code). I saw it was going to 182 inches. Not good. The problem was either software or the BMDC. It passed B3T, scandisk, and defrag. Nothing to lose, I reloaded the software and problem went away. Otherwise I would have ordered a BMDC. Funny though, this machine had the original hard drive with the Bridgeport part number and the SPINRITE log on it. 14 years old.
Have you checked the logic power supply? That can cause issues. So can a bad ISA slot, bad memory, etc. When you turn the drives ON, try and move the handles by hand. Just to see if the drives enable.
No easy answer here.

George

[dreammstr6]

i feel i have ruled out the eztrak program, hard drive, ram, mother board, axis drives, motors and encoders. i put the suspect bmdc card in a working mill. i ended up with same problem except while it was in my mill in manual mode the xyz numbers would change when moved by hand. returned the card to original mill. numbers won't change at all unless i play with it to get it into jog mode then the numbers will change if i move the jog wheel but the axis doesn't move. what's funny is when i put the card in my working eztrak sx it was also missing the selections 4 and 6 and the arrow key selections. when i put my working bmdc2 card back in everything was normal. i'm assuming the software being loaded to the bmdc is getting scrambled. could that explain the missing selections?