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I dont use my takisawa that much, so I am always having trouble with the limit switches (plunger type). So, I was unsticking my x, pushing up and down, with the control on I think, now I am getting a 401 servo alarm. Boots fine, move the x .001, hear the motor searching and boom, alarm. Axis drive shows a OVC light on.
Thanks for any input.
Whats the part number of servo drive?
The drive board is numbered A20B-0009-0320/100. I believe the OVC indicates an overvoltage conditon. I am suspect of the two transitor packs. I dont know what resistance to look for, so I am just going to compare them. Its tough without manuals.
Thanks for any input.
Support the turret so it does not drop.
Remove the X axis motor from the ballscrew.
Leave it hooked up electrically
Have someone try to jog the X axis
Do you still get the same alarm?
If not check for mechanical bind
If so check motor leads (disconnect wires from terminals 5,6,7,8, on servo drive with power off ) 5,6, to 7,8 should read about 1 ohm. 5,6 to ground should read open .
Thanks, I will try and resolve the problem this week. I was not having any trouble with the axis prior to the problem. Not sure it would be a mechanical bind. I will update.
Thanks again.
OVC is an overcurrent alarm - probably axis in a bind
Arr5ow Control is probably right.
A motor that won't turn because of a bad ballscrew or bearing will throw the OVC alarm as soon as you try to move it. Also, some Fanuc motors have an electric brake inside that locks the motor from turning when the power is off. Motors with brakes are typically used on slant-bed lathes or on the Z axis of machining centers to prevent the axis from drifting down when you shut the control off. If the brake won't release, it could be because of a blown fuse on the brake power lines, or a bad brake coil in the motor.
If your motor does not have a brake, look for something mechanical preventing the axis from moving.
You guys were right!
Drive was just fine. Axis was locked up. I use my machines everyday and assume everything is getting oiled. There is something to say for periodically removing the covers and getting a visual. Thanks again
traducción del español al inglés
HELLO TO ALL, I HAVE THE FOLLOWING PROBLEM!! WE HAVE A MACHINE AMADA FANUC 6M Q-344, AND I had the 401 The-READY ALARM signal (VRDY) for velocity Tc! of X-, Y-, or T-axis is off .. TWO engine running smoothly but I HAVE NOT SHIFT,, AND THE MACHINE IN Relocate 0,0,0,, CLEAN BARS X, Y,, REVIZAMOS FUSES, BUT NOSE IS THE CABLE THAT SENT ME THE SPEED CONTROL SIGNAL ????. If someone can I DO, THANK YOU !!!!!!
I thought I was in the same situation..turns out, maybe not.Quote:
Originally Posted by Sprew
Greetings all. Sometime lurker, first time post. Situation is this: For the past 2.5 months I've been running a Matsuura VC-760 with a 6M control. Its my first job back in the industry after a 3 year hiatus(and I was still more or less a newbie when I left 3 years ago), and I'm taking over a machine that has been well abused over the last 28 years. the evidence of crashes is all over the tooling plate that is bolted to the table and in all the ruined tool holders scattered throughout the drawers. A week ago Monday(mid day) it threw a 401 servo alm during a peck cycle (7/8" drill in 1/2" HRS) about 30 parts(3 holes each) into the part run. Power down, restart etc. Couple more parts, Bam, same deal. Rinse and repeat. Managed about 5 parts in 3 hours. Next morning situation was worse, machine was only running for about 25 minutes before it alarmed not even able to finish 2 parts, alarmed 4 times in the span of an hour. Always seems to happen in a peck... stopping about .020" from the bottom of the hole up to that point in the canned cycle. But when I reprogrammed for two passes of G81 it also did it. :-( Spoke to a tech out of Oakville on the phone, and he told me to check for 100V going to the drive (did I mention I'm a newbie? I can swing a multi-meter as good as the next driveway mechanic, but I don't know from CNC systems), and that "...it sounds like an intermittent short and that you should check your worklight for a coolant related short because the worklight is also 100V". Worklight? Don't have one, buddy. etc etc.... ok, so soonest a tech out of Montreal can be here is a week. I got "re-assigned" to less interesting work for the next few days. Yesterday tech shows up, wants to see it running and hopes to get the alarm. Machine decides to work, and finishes the partially drilled parts still in the vice from a week ago(4 and a half holes). Tech wants to see machine run with no tools, just up the feeds and rapid to try and force the ALM. He leaves after an hour(half of which is me just looping the prog with an empty spindle) with no alarm. He told me what to look for on the Z axis drive LEDs and pointed out that the Z axis ways looked a little dry and I might want to lube them up manually to eliminate that as a posibility. I decide to rack up another pair of parts and start cutting again without spraying the ways down in order to get an ALM and get him with eyes on and tell me what's going on rather than have some phantom alarm that might have been caused by under lubrication. One and a half holes later, BAM, 401 servo ALM. Call tech back from another shop down the road. OVC LED is lit. We climb up onto the machine and get a good look at the ways. DRY DRY DRY with dark tar-like gobs smeared in places near the top where its hard to spot. He's 99.9% sure the OVC is due to the servo motor trying to heave the spindle carriage over dry ways through that epoxy like tar/varnish. He says he could spend the next day or two cleaning out the lube sys at $120/hr... or I could. Guess what the company decided? so the last day and a half I've been up to my armpits in 10-28 yr old grime and grease. I cleaned out the upper lube manifold, removed the lube reservoir scooped out a half cup of black sludge, cleaned out the in-line filter of more of the same sludge, refilled, pumped, bled, pumped, checked to make sure there's oil at all six points around the two ways, even cleaned and then re-oiled the counterweight roller chain and rollers. She's wetter than I won't say what.... Mop up all the excess oil and WD40 before it gets into the sump.... cue up the prog... aaaaaand 2 holes later....BAM. 401 servo alm. whaaaat?!
why why why? So was the lack of lube not the cause? A relay? a fuse? Faulty contact? Is the ball screw shot(I can't really get at that in the time I was given and wouldn't know where to start)? Did the lack of lube strain the servo/drive over an extended period of time and damage one or the other, or both? Machine works fine in MANUAL: traverses up and down like a champ. Drilling Op is nowhere near a limit switch. Could it be a simple as an axial overload due to the drilling op?
GHAAA! Don't know when the tech will be back. Help. TIA.