TC4 error - auxfuncs: spindle time-out

[emvali]

I have a TC4 with DX32 control, everything used to work just fine.
Yesterday, while initiating a rigid tap cycle, the tool was picked, the spindle lowered to starting position at the right RPM, then, while stopping and turning to 0 position as usual with a rigid tap, I noticed the spindle turns very slowly, several turns then stops and this error message is displayed:

auxfuncs: spindle time-out

Machine stops, drivers are turned off and while reinitiating seems as it is loosing the tool changer position too.

According to the manual, the dynamic braking resistor circuit, or the dynamic brake time in spindle drive parameters is not set correctly, also BDMC or AXS cards or Spindle Drive may be the reason for this error.

Everything works ok until the rigid tap cycle starts, the machine changes tools, everything looks ok except for this error.

Anybody had this error or may have an idea where to look at?

[machintek]

Lets look at a few things in a logical manner.
Since it will change tools, the spindle encoder functions in that it achieves orient and I am assuming that spindle speed is being achieved correctly. It also means that the spindle drive balance is set close enough. Otherwise it would not finish changing a tool.
I know there is a encoder in the spindle motor as well. It may this one that is giving you grief.
Have you tried this with the electrical cabinet door open and watched the spindle drive for a fault display? The undervoltage fault occurs when the drives shut off. Do not be concerned with that one.
I have had only one failure of this encoder in the spindle motor.
Have you tried tapping without evoking rigid tapping? Just to see what would happen?
Is this the first time you have tried rigid tapping? I know on some machines it was a option. We would call Bridgeport, give them the serial number of the DX32 control and they would give us a cryptic code to put in to enable it. Just thinking out loud. It has been a while since I played with this.
In Maintenance page watch the s axis error and run a rigid tap cycle. The error should be a degree or less (if I remember correctly). That may shed some light on it too.

George

[emvali]

Thank you for your reply, here are some answers:

Spindle speed is achieved correctly, although during the last times I noticed it dropped a little from the setting, what I mean is if usually it was always within 1-2% now it is 2-4% deviation from setting value. It changes tools perfectly too.

I had no idea there is another encoder in the motor - my model is the 80-8000 direct drive without gear.

So now I know what is F-602 that is dispalyed on the controller when the cycle fails and drives are switched off - I was confused when I looked in the manual at the controller's error codes explanations. Except this everything is ok on the comtroller's display.

No, I didn't tried regular tapping - I usually work with rigid only, and the option exists, I used it many times and works great.

I will try the maintenace page today and see what happens.

About the error probable solutions as described in the manual - I located the "dynamic brake resistor" or I hope I did, it is behind the spindle controller, a large rectangular white power resistor, also will check it today.

What is the "dynamic braking time parameter"?, I assume it is set in the spindle's controller but the manual says nothing about it.

One thing I don't understand, or maybe confusing, but when a tool is changed the spindle rotates slowly to orient the tool holder and brakes - and this works, isn't it supposed to be the same operation?

I will resume testing today, I had another problem, while opening the spindle's column covers I am not sure how it happened but I found the tool clamped limit switch broken - today I am getting a new one and I will resume testing.

[gus]

stupid thought......spindle speed too high.............i mean, it works for everything but the rigid tap........

[emvali]

The speed is set at 400.
I loaded a program that I worked with about one month ago and does the same thing.
I don't know why I have the feeling it is not a hardware problem although it is an old machine after all so everything is possible.

I wonder if it's possible some setting is not set correctly, or changed by mistake.
Everything else works perfectly, this is what's strange with this situation.

[machintek]

Dynamic braking resistor is used by the spindle drive to dump energy to. So if it was bad the drive would fault when spindle is braking.

George

[emvali]

I tested today a short tapping program (not rigid) and it works.

The reason I asked about the dynamic braking is because an resistor open circuit or wrong timing parameters are 2 of the reasons for this error message stated in the manual.
The other options are the BMDC or AXS cards or the spindle drive.

Where is the spindle's motor encoder, I mean the internal one - is it accessible without removing the motor?

[emvali]

While reading the maintenance manual for the who knows how many times during the last days, I found at the spindle's controller chapter a solution for "spindle will not orient in the desired position" and basically this is what happens - it starts the rigid tap cycle at the set RPM, goes to Z, stops, orients, brakes and then begins the up/down tapping. In this case, during the orientation it turns really slow until the time-out error is generated.

The problem according to the controller's chapter is "spindle drift offset setting is too high" and it is adjusted by raising or lowering the C1-11 parameter.

On my machine was set at -21, I palyed with it up/down, at -18 works ok, so does up to -10, so I left it at -16 and it works !!!

But being the suspicious type, I ask what is the reason, after all it worked perfectly with the previous parameter.

I have the feeling the encoder is a little "tired" - while working normally, the spindle shows fluctuations between -4 to -10%, sometimes I see even more for a glitch. If I remember, before the error happened it was quite accurate, no more than +\- 3 to 4%.

Any ideas?