Sodick Wire EDM

I am operating Sodick VL400Q Wire EDM, I noticed the Water Resistivity in the machine keep raising rapidly. What could be wrong? How to fix it? I replaced the Resin. I set the Max Resistivity to 60000 but now it is 990000. Hope someone knows the answer.

I would give James machinery the local Sodick agent a ring, I have always found them very helpful.

The machine i run is about 25years older than yours, so my only thoughts are clean the conductivity probes, or the valve to the resin cartridges is stuck open and not shutting off when the water reaches max resistance.

san73 said:

I am operating Sodick VL400Q Wire EDM, I noticed the Water Resistivity in the machine keep raising rapidly. What could be wrong? How to fix it? I replaced the Resin. I set the Max Resistivity to 60000 but now it is 990000. Hope someone knows the answer.

Click to expand...

You can also repost the essence of this post in the EDM section of the forum - you might get more Wire EDM expert eyeballs in on your problem.

https://www.practicalmachinist.com/vb/edm-machining

Hi san73:
Are you sure it's the RESTIVITY that is rising and not the CONDUCTIVITY?
The first term is essentially the inverse of the other.
If the resistivity is rising the DI resin is essentially too effective in stripping conductive ions from the water.
If the conductivity is rising, the DI resin is not doing it's job, and the conductive ions produced by the cutting action are not being stripped out of the water.

For the resistivity to rise, (as snapatap describes in post #2), water must be flowing through the resin bed, so the valve to the DI circuit must be open and the DI pump must be on.
The conductivity probe tells the control when to turn that subsystem on.
So a fault in the conductivity probe is the usual reason for the DI pump to be on when it's not supposed to be.

The poor man's way to check it is to short the probe with a screwdriver and see what it does to the resistivity (or conductivity) reading on the meter and whether the DI pump turns on as it should.
The conductivity should go up to infinity or the resistivity should go to zero, depending on what the meter reads (some brands read resistivity, some read conductivity; I don't remember which my old Sodick read)

If the meter does not detect a change, the control will never know the water has too few or too many ions in it.

So if the shorting procedure does not bring the conductivity to infinity the control interprets that as no need to turn on the DI subsystem and the actual water conductivity will be too high.
If by contrast, the probe is always shorted (screwdriver or not), the DI subsystem will always be on and the actual water conductivity will be too low.

Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

san73 said:

I am operating Sodick VL400Q Wire EDM, I noticed the Water Resistivity in the machine keep raising rapidly. What could be wrong? How to fix it? I replaced the Resin. I set the Max Resistivity to 60000 but now it is 990000. Hope someone knows the answer.

Click to expand...

Hello, we have a VL600Q and VL400Q, we had a problem with one of the fuses and the resistivity increased as you said.

The technics in Mexico made the change of the fuse in less than 1 hour and it went back to normal.

Another thing that seems too easy is water level, if its too low on my machine it causes problems. Always good to eliminate the easy stuff first, also remove the input hose and verify that the water is being pumped through the resin bottle when the probe signals the solenoid.