Sheffield Measurement Cordax Discovery D-12 Problems

[ninja-noir]

Hi, we purchased a Cordax Discovery D-12 machine. and it was working perfectly by us for few days. By the previous company it was used daily for parts inspection. The machine was on but not doing anything then suddenly it moved by its self in the x,y and z direction and then kicked up an alarm mp-176. even after clearing the alarm it still jerks in the same direction as soon as the servos are powered and kicks up the same alarm. We are really having trouble getting help. Hexagon the new owners of sheffield measurement, we asked them for help and still waiting to hear from them. We are in Cape Town South Africa.

Here is a link to the video of what the machine is doing.
That is the computer board. Cant find any info on that code that it gives either.
Any help would be appreciated

 

[Bakafish]

Older machine, worked initially, left on for a long time and then spontaneously erroring? Sounds like bad capacitors to me... Have you left it unplugged for a few days to see if it recovers temporarily?

 

[ninja-noir]

Older machine, worked initially, left on for a long time and then spontaneously erroring? Sounds like bad capacitors to me... Have you left it unplugged for a few days to see if it recovers temporarily?

The machine Was used, and ok it is old but it was being used. It did not stand still. be bought it from a company that was closing down. and leaving it of over weekend did not help

 

[Bakafish]

Old in the sense that electrolytic capacitors of a certain age tend to become unreliable, not that there's anything intrinsically wrong with a well made machine. Check the voltages coming off the power supply, check for AC ripple as well (a sure sign of filter cap failure.) And reseat all the connectors, ideally with Deoxit or contact cleaner. That's all the low hanging fruit.

 

[gregormarwick]

It's certainly possible that there are dead caps, but it's not a likely cause of that behaviour IMO, especially not when the machine has been on for a while. Dead caps tend to manifest as obvious problems at power up, that gradually improve while the machine is turned on.

This is speculation that you'd need to confirm, but old CMM likely means analogue DC servos, probably in velocity mode. Some pictures of the amplifiers and servo motors might help confirm/refute this.

The low hanging fruit in that scenario is stuck tach brushes, carbon build up in the commutator, broken tach wires. Next most common thing on old analogue DC amps that can cause a runaway in one direction is a shorted h-bridge, in which case you are looking at replacing the amp or getting it repaired by someone who can repair electronics.