1995 Fadal ht 10k rpm 4020 spindle drive issues

[Delw]

OK this sucks cause it happened on a friday night.

new machine been go through completely. had for 7 days ran 3 days just playing around, last night the spindle will running at 8k just slows way way down to about 1k rpms then kicked back on to 8k No alarms nothing.

The spindle load monitor should NO LOAD at all. the spindle speed adjustment didn't work at all while is was dwindling down in rpms.

happened three more times , so I said *^&* and went home, read this site this am and checks fans wire connections everything. fire it back up this morning ran for about 20 mins same thing. tried different rpms same thing.

took off air cleaner off the top of the motor to make sure I was getting free air through it and let spindle run same problem at 4k rpms, had the same problem.

if I touch the motor its warm (normal warm)but not hot.

about 20 mins ago it did the same thing, this time I let it go way down and finally got a overload alarm. you could hear the motor pulsing just a tad ( rpms on the baldor spindle display in back of machine showed a about 100 rpms pulsing) I shut the machine off , fired it back up and for the last 15 mins its been running at 1500rpms with no problems.
I did get a alarm on the led display on the drive this time( but when typeing this I forgot what it was go figure ) and the screen said motor overload this time. never got one before
it has a baldor drive with rigid tapping.

It almost sounds like a wire is loose,( because the speed adjustment knob has no control nor does spindle load meter work when it goes into this state) , when it was running and doing the problems this morning I touched every single wire.

Any ideas?

Delw

[Delw]

Played with it till about 9pm last night, the spindle went down about a dozen times times to the low unadjustable rpm then kicked back up to normal. no over loads or error msgs.

it also doesnt make any difference if the rpm is slow or highspeed, its not a over heating problem as I have 2 big fans blowing in both doors( its kinda cool in the shop as well)

Delw

[HuFlungDung]

In a lot of these variable speed drives, the control's speed signal output has a voltage between 0 and 10 volts or perhaps -10 to +10 volts if the drive is reversible without using another forward/reverse input. The exact voltage on this input is proportional to the output frequency sent to the motor, thus the speed is controlled.

I have no idea if you can determine which control terminals on the Baldor drive are used for this speed input signal. If you have the Baldor manual, this should not be too difficult to find out. You can check this signal between that identified speed input and common, with a VO meter. If you use an older analog type meter with a needle, it will show you what is happening to this voltage in real time when the drive is acting up. If this particular input shows a varying voltage (when it should hold steady), then you know that the problem is in the control signal from the computer. This might turn out to be a component failure in the PC or a power supply going bad. That is my WAG.

[Delw]

I will see if I can find a manual somewhere, thanks

One other thing it did it today again and I hit the spindle stop button. This did not shut off the spindle at all, just stayed at approx 1000 rpms then when it finally caught it shut the spindle off, this went on for 2 mins with it just spinning( at the decelarated rpm) basically it no buttons give me any spindle control at all when it goes through its phase.

would that be the encoder on the spindle motor?

[ASIGuy]

Generally if the spindle fluxuates when commanded and the load meter seems to bounce around, you have a problem with the spindle encoder. Alignment, dirt, ect. The loss if control tells me that you have a wiring or board problem possibly. I would shut the machine down, carefully and methodically reseat all boards in the control rack, and all wires to each board, and all cables plugged on to the 1060 motherboard and see what happens. If you want to try a spindle encoder, try FadalCNC.com.

[Delw]

I think its fixed now. after being on the phone for 4 straights days and checking every possible problem including replacing the encoder this morning. I finally said screw it and called the people we ordered the machine from to order a inverter, well I forgot the number and had there service guys number so I called him.
he came up with a really bizzare answer for me to check so I said ok hang on the phone as I had a screw driver in my hand.
I had to open the inverter case and 2 wires were keeping me from opening it fully. so he told me to call him back, as he was in the middle of something.
I undid the wires opened the case and noticed that one of the blue thick nickle sized MOV parts vibrated. I touched it and it fell to the floor.
he had told me to check this and see if they were connected ,loose or even there on the bottom of the control box. Apparently this has happened a few times in the past with the older sweo drives (1995 model).

went to the neighbors shop and got his solder sucker and then he resoldered it back on, the whole process took about 20 mins came back to the shop hooked it all up and ran a bunch of parts for 3 hours at 10000 rpms ( just for the heck of it and had not had one error).

we have gone through the entire machine, every possible senerio was gone through. I would get a "oc" Lower case error on the inverter once or twice then yesterday I got it about 12 times including a "dclo" (lowercase) error which I got for the first time since friday night. Lower case errors on baldor drives according to baldor techs mean "uncertain errors"

I talked to fadal and baldor both. there were all helpful , Fadal ( Gary) even called me back a few times to try this or that. Gary at Fadal tech.. support is a drive whiz. and very maticulous (sp) and will talk you through everything step by step of the way.

As I am typing this the machine is running at 10k, with my luck it will probally die as soon as I hit the "post Quick Reply button" this is however the longest it has run with no dramatic spindle speed changes on the rpm led on the drive ( its varying about +- 1 rpm, before it was varying about +- 20-30 rpm )

I got a few drive tests for the SWEO drives and if someone thinks It would help someone else in the future it I will put it together. it is extreamly easy to disconnect the drive from the control and run it off a 9volt battery , doesnt take any special tools or pins either. The machine control doesn't even have to be turned on, just the main power. what this does is let you know if its a drive issue ( meaning inverter , motor and encoder) or a control issue ie controller card or wiring in the control circuits.

On the bright side if this continues to work my cigarette intake will be about 2 packs less a day

[ASIGuy]

Great job. I would love the details if you have the time to assemble. I troubleshoot with machines daily and always are looking for new ideas to common issues.