Need Help!- SV013 Alarm Fanuc 11M

[kalawa]

We have a Mitsui Seiki horizontal milling center with Y axis brush dc servo motor A06B-0653-B212 and drive A20B-00009-0320/15E.

The motor was removed for making grinding noises and brake was found to have been fitted incorrectly previously. It re-set tested and re-fitted. The motor commutator was cleaned with fine wet/dry.

On re-installation the motor was found 'humming' but was turning both ways (without load) for a while then it stopped with above alarm. Fitted onto ball screw but still did not turn but humming gone.

Checked relays and all ok. But found that when Y axis is moved, CRN2 relay immediately cut out with above error and OVC red light on the drive.
Other axes seemed fine.

I would appreciate if anyone can help me on the above problem

[Al_The_Man]

Try feeding the motor armature only with a source of DC such as automotive battery.
See if it turns OK both directions smoothly and check current.
Al.

[kalawa]

Thanks Al for your prompt reply.
We put on a 12v car battery and onto pins C & F and then D & G on the armature receptacle but no rotation noted. This is after supplying power for the brake.
You mentioned 'armature only', are we doing it correctly I wonder going through the pins?

[Al_The_Man]

What is the MS number of the motor receptacle? 18-10 insert?
check for resistance, IIRC it is normally A & B pins.
Al.

[kalawa]

part no. on receptacle is JAE MS3108B28-20S-ZN, with 10 bigger size pins and 4 smaller size ones. From electrical dwgs pins C&D are for 2 off YA1 leads, and pins F&G are from 2 off leads YA2 from Y drive to motor.

Resistances are C - F =0.8ohms; C - G = 0.8 ohms; D - G = 0.8 ohms; A - B = open

Thanks in advance for your help

[fanucman]

omg.. dont put any battery on the motor it isnt going to help you..

get a volt meter remove the yellow cap and measure the resistance across the tach.. its mots likely the problem.. you need u see 100 ohms.. if its more than 10% out of spec replace it.. inspect the com, make sure it is clean.. if not use a eraser to clean off the carbon build up.. also check the brushes on the motor them selves..

[Al_The_Man]

C&D are one connection and F&G are the other armature connection, so this is where you apply armature voltage, either between C&F or D&G.
If you have the brake picked up, it should turn with a voltage applied, this may be where your problem is? is the armature free to turn when the brake is picked up?

Originally Posted by fanucman omg.. dont put any battery on the motor it isnt going to help you.. .

I don't necessarily agree with this comment, do you want to elaborate?
I have been using this method for many years on the Getty's/Fanuc motors and others to do a simple basic test.
Al.

[fanucman]

well the other stuff i listed is just a better way of troubleshooting this problem that's all..

[kalawa]

we have gone with the car battery,remove the brake and the motor turns ok....phew!! now we are trying to re-set the brakes again and do another bench check since it appeared intermittent when last tested...
- break resistance 170 ohms.
thanks for the ideas and will keep you posted

[kalawa]

re-set the brakes(R=170 ohms) connect 100vac to break rectifier(with a 32A circuit breaker), heard the break move, then rotate armature spindle cw and it was fine.

But upon turning ccw, the circuit breaker opens and break resistance measured opened. It appears that the only way to get some further tests done is to remove the breaks and go through the same process again.

But, why would the armature orientation have anything to do with the brake circuit? We are removing the brake currently to check on wire shields but i would appreciate some theories behind this anomaly and suggestions on a quick and cheap fix.

Thanks in advance.

[Al_The_Man]

I would set up a separate supply for the brake, or is this what you are doing and the breaker trips?
If the brake is the tripping the breaker, it sounds like it may have ground on it.
Are you turning the armature manually or under power when the breaker trips?
Al.

[kalawa]

Thanks Al. We only supplied power to the brake and turned arnature by hand when the breker tripped. The brake leads were found squashed and bare wires exposed, were repaired,power supplied to break and armature was turning cw and ccw, by hand.
But when fitted to the machine and run by the machine control, the motor turned cw only and tripped with alarm SV011 when turned ccw.
Now we are removing the brake again to see if we can do more bench checks on it.