STOPPED NEED URGENT REPLIE.

[arob]

HI GUYS,
Have a superslant with a GN6T FANUC control, from start up procedure the DRIVE FAULT light comes on and the screen shows alarm 401, which says ''velocity control ready signal (vrdy) has turned off.
My problem is i don't know how to turn it on, can any one help me.
thanks,
regards AROB.

[krutch]

I don't have an answer for you, but will be watching this as I too have that problem. Happened after SB was moved to new building. Haven't tried to run it since problem arose. Hope some one can help us soon!


Krutch


Mentally confused and prone to wandering!!

[KTECH]

Did any one figure this problem out. I now have this problem too???? HELP

[emexcee380]

The 401 VRDY alarm means that a servo amplifier is NOT READY. You probably have a single amplifier driving the X and Z axes. If the amplifier is not in a FAULT condition with one of the red led's lit, your machine is most likely in a E-STOP condition.

Make sure the panel e-stop (and any others) are released. Try pushing in the OVERTRAVEL RELEASE button to see if the servo amp will go READY. If so, you're on a hard overtravel limit switch or one is stuck.

Finally, look for a fault on the power supply (probably called an INPUT UNIT on your machine)for a fault condition with corresponding red led on.

Good luck,

emexcee380

[krutch]

Originally Posted by emexcee380 The 401 VRDY alarm means that a servo amplifier is NOT READY. You probably have a single amplifier driving the X and Z axes. If the amplifier is not in a FAULT condition with one of the red led's lit, your machine is most likely in a E-STOP condition. Make sure the panel e-stop (and any others) are released. Try pushing in the OVERTRAVEL RELEASE button to see if the servo amp will go READY. If so, you're on a hard overtravel limit switch or one is stuck. Finally, look for a fault on the power supply (probably called an INPUT UNIT on your machine)for a fault condition with corresponding red led on. Good luck, emexcee380

Finally, some where to look! I have not even powered up since I posted this problem. It will be some time till get back the machine as I have other things to deal with.
Thank You, emexcee, this just might be the lifesaver that we in this posting need. Although I seem to remember a red light on in the panel that I identified as related to the VRDY.

[KTECH]

OK the e stop is depresssed, there is no overtravle relese switch either. this thing is early 80's gnct controller. I did have the 401 alarm come up about 6 months ago and it was a blown fuse. No blown fuse this time. Its on the z2 axis. I cant get the z and x to even home now cause there is a 420 alarm for those. I think that one is cause if its not close the home on start up it will post that alarm. any other thoughts???

[KTECH]

Any one get any where with this?? I think its some thing at the drive like the motor is toasted. Going to check it tonight after hours

[emexcee380]

The 420 alarm means, " the position deviation amount during stop is greater than the setting value."

When an axis is moving there is a parameter value that sets the amount that the encoder feedback can vary from the actual commanded position.

Likewise, when an axis is at rest (stopped), there is a parameter value that sets the amount that the encoder feedback can vary from the actual commanded position.

If the alarm appears immediately when you power ON, it would seem that as the axis is trying to hold position, the encoder feedback is exceeding the parameter value for "position deviation amount during stop".

I think I would first check the parameter setting for the offending axis. For a
Fanuc 6T control I'm not sure what the parameter is. (For the next generation Fanuc control (the 0-series) the parameter is 593 or 594 for x and z respectively.) Look in your maintenance manual and see if you can determine the correct parameter. The description will be something like "Position error limit value during stop".

I believe your machine is equipped with DC servo motors. (yellow covers over the encoders.) You might need to clean the brushes to allow the motors to position correctly.

If your machine is equipped with individual servo amplifiers for the x and z axes, you can swap the to amplifiers and see if the alarm follows the amp for the offending axis.

Good luck,

emexcee380

[KTECH]

Yes that is correct on the 420 alarm as well to a certain extent. It will also trigger if it is to far away from home at start up. I tried the swapping thing with no luck. I think it comes back to the velocity controle board. Since every thing is in German right this is going to be easy unless you know what your looking for.

[KTECH]

I have bad news for you guys out there it looks like a bad servo amp... I have a tech looking at it.

[Al_The_Man]

Is the 402 alarm as soon as you power up?
It could be encoder, but one way to test the motor itself is to remove the armature leads at the motor or the drive and power up.
You should not get a fault until you try and move the axis, then it should be following error after a certain expected distance has elapsed.
Or there is a possibility that mechanically something is binding and preventing the in-position point to be reached?
Al.

[KTECH]

Just checking back. Did anyone get any where with this problem? going on 4 monthes now my machine has been down... Also i was wondering what amp board set up you guys have out there. My lathe is fanuc controle with seimens drive boards. My local Hardinge distibutor says they never came that way. Any replies would be great on this. I do have some docs on the seimens boards but i need more info on the matter. They just started dealing with harding and will not give me contact with hardinge even. HELP!!!