Brother HS-350 EDM issues, high conductivity, no discharge

Hello All -
Long time reader, newbie poster. Been working with Brother EDM's for 15yrs (HS-350, HS-50A) with recent problems with HS-350 startup after a prolonged shutdown. Machine came right up (without any preventive clean up), though conductivity quite high (5 on POS, page 2 and 537 on Alarm, page 2). After few days conductivity now at 7 and 1233. No error messages or alarm but no discharge either. WATER, WIRE, ELEC all operational, power meter goes Full Scale, no arcing and then wire makes contact with part and get "contact" message on CRT.

We are doing the usual - replacing DI water, resin, cleaning filters but struck by lack of any alarm which cause total lack of discharge. I have read that high conductivity can cause issues but never downright loss of arcing and w/o any error/alarm.

As an aside - trying to follow I/O on Alarm, page 2 but confused by its structure. The precursor HS-300 has 8bit I/O but this seems to be double column (as in 16bit??). HS-350 manual, section 3.3.8, screen 19, lists the I/O signal 16 columns as 0 1 2 3 4 5 6 7 8 9 A B C D E F but no details! Any input on I/O structure most appreciated.

Thanks - enkad

enkad,

I have seen water conductivity high enough to completely stop the EDM process many times.
The fact that you aren't getting an error on the machine makes me think your DI probe it dirty.
Do you have a handheld probe you can verify water conductivity?
You can buy them for $150 or so....don't buy the probes meant for hot-tub use...
As I'm sure you know, if your machine thinks the water is fine, it won't run it through the DI system.
Dirty probes are common after extended shut-downs as the "funk" dries and hardens on the previously always submerged probe.

I'm sorry but I am no help on the I/O issue.
Charmilles may still have someone on staff who can help you with the pin out.
1-800-282-1336 - Charmilles

Good luck,
Jay Crumb
Advanced EDM, LLC

JayCrumb said:

enkad,

I have seen water conductivity high enough to completely stop the EDM process many times.
The fact that you aren't getting an error on the machine makes me think your DI probe it dirty.
Do you have a handheld probe you can verify water conductivity?
You can buy them for $150 or so....don't buy the probes meant for hot-tub use...
As I'm sure you know, if your machine thinks the water is fine, it won't run it through the DI system.
Dirty probes are common after extended shut-downs as the "funk" dries and hardens on the previously always submerged probe.

I'm sorry but I am no help on the I/O issue.
Charmilles may still have someone on staff who can help you with the pin out.
1-800-282-1336 - Charmilles

Good luck,
Jay Crumb
Advanced EDM, LLC

Click to expand...

Hello Jay - Thanks for your input. Much Appreciated. Yes the DI probe was dirty, in addition to dirty water. cleaned it and conductivity back back down to 0-1 on POS, pg2. Discharge does have another glitch as well - will post as we work our fix on it.

I/O pinouts is another matter already. We figured a few out by creating deliberate errors but there are so many...

Best Regards - enkad