198 Alarm (Precharge Failure) TSC Not Working

[Eric MFG]

Hi,

We have a VF3 with coolant through the spindle and have been having issues with a hum from behind the spindle head with an unclamp alarm. I replaced the pre-charge solenoid and cleaned things up about three weeks ago and the machine was fine for a while until the second solenoid went bad and now we are getting the same problem a hum and tool unclamp alarm. Can the I/O board be bad? What else can I do to figure out the root cause?

When I disconnect the pre-charge solenoid the machine tool unclamp alarm clears but then we get another alarm TSC pre-charge failure. Might not be a good Idea but can we bypass the pressure switch just to get a job done thats on the machine now?

[haas tech #3.]

Hi Eric.
The solenoid is activated with 115 VAC. if the voltage is low it will make a humming noise. It will also make the noise if the pre-charge air pressure is not set correctly to 3.8 PSI. The way that you set the pre-charge air pressure is by installing a gage with a T fitting. The pre-charge air line needs to be connected if not it will alarm out with a pre-charge failure. I can assist you more effectively if you call the Haas Automation Inc service line at 1-805-278-8500 prompt #3 for service.