HAAS Spindle issue

So the HAAS has a spindle & drive issue currently. We are still in the process of troubleshooting. Currently once the spindle is warmed up, you can hear the bearings. Then there is the drive fault, at this time we are not sure if they are related yet or not. This drive fault only tends to happen in the 1125-1250 RPM range with a drive output frequency of about 124hz to about 132 hz. We may pull the cartridge to take a look, Thats kinda up in the air.


has it been crashed lately?
if it is the 123 SPINDLE DRIVE FAULT - This can be caused by a shorted motor, overvoltage, overcurrent, undervoltage, failure of drive or shorted or open regen load.

this has occurred before while in the old machine shop. I long suspected it was a voltage issue caused by a dip in the line, but it could be more.

Here is a link for some issues: LINK

No recent crashes. The fault is a 126 error, at around 1200 rpm.

Not that I’m aware of. The spindle Drive fault we are getting is output phase loss on the drive. This only happens in the frequency range of 124-132hz. Ive checked the motor, Ive checked the dc bus(not under load though). If it were a shorted motor we would get the earth ground fault error. It may be as simple as the IGBT’s not firing at those frequency ranges. I checked the input voltage, but not while running. We had 245 volts, keep in mind before those say we only have 208, the HAAS has a power correction transformer to boost the input to an acceptable level. I do want to do more testing under load, also I want to remove the drive cover to see if its the upper spindle bearing or lower. In the cartridge, there are 3 bearings in the lower half. Still to check is the spindle oiler as well, I can’t seem to find in my short period of looking, the spindle oiler we have. The newer machines appear to use the Bijur pumps for spindle oilers.

It’s going to be interesting to see what we come up with. I’m hoping it is not the spindle bearings, & something simple.

This is from a Haas Service manual for fault 126. Keep in mind this is on a newer machine.

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It’s been a minute but just to eliminate the simplest solution. Some HAAS use a WYE-Delta contactor for low speed changeovers. I think the changeover is usually at 2500 rpms but not sure with a gearbox. I’d certainly make sure to have a look at those contactors before diving too deep.

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Spindle oiler might be hidden behind the sheet metal in the back corner. Look for the little sight glass.
The Bijur pumps should just be for axis lube.

Yeah I’m going to pull the cover this afternoon.I could see the oil movement in the strainer last night. I want to get a closer more definite look at things to rule stuff out.

How’s your world going Ryan, been a minute thats for sure.