1991 Haas Vf-1 servo axis alarm 103

This just happened yesterday. hit the cycle start button and the table moved about 2 to three inches, then alarmed out. #103.
was able to finish the job at 25% rapid rate.. but every time i went to full rapid the table would move then alarm out..

Today i took the covers off, pulled out the brushes, blew out the motor. brushes are about 3/4 worn. put back together and ran a cycle.
the same thing happened.. table moves about 2 to 3 inches then alarms out. now i noticed i could handwheel the table all the way over. the hit g28. it wil rapid all the way home.. also i could move the table to the far right side and hit cycle start. it will rapid to position. Am i face with a bad spot on an encoder?

Look into replacing the X axis cable. They are available from the factory still for that model P/N 93-1500 should be the one.

They lay in the coolant and chips all there life then get cracks in the insulation causing shorts.

I have three of these machines and that is the first thing I do before putting them into service on my floor.

Good luck,

You can ohm out the motor and cable to verify.


But as sagespecialized said...pretty often it is the X Axis cable...bends with every Y axis motion....only so many times back and forth before cable cover lets go which localizes bends to a point, then it's just a matter of time before the wire fatigues. Cable sitting in coolant and crap does not help either.

Not sure how true...but have been told by techs you overheat the servo amp components each time you clear alarm to give a try without success as you are sort of running a direct ground, or shorting it out. Only so many times that can be done before you need to add an amp to the list of parts.

X axis cable replacement on our 91 machines is a true thrill. Not too bad on later machines, but the 91 has a 90deg lug you need to snake cable thru...you'll see or your tech will tell you all about it.

The limit switch as well, inspect from switch too the plug. I repaired mine with a splice and heat shrink tubing for submersible well pump. Symptom was the same as yours, could run slow but rapid movements caused intermittent failures.

The limit switch cable as well, inspect from switch too the plug. I repaired mine with a splice and heat shrink tubing for submersible well pump. Symptom was the same as yours, could run slow but rapid movements caused intermittent failures.

BGL said:

The limit switch cable as well, inspect from switch too the plug. I repaired mine with a splice and heat shrink tubing for submersible well pump. Symptom was the same as yours, could run slow but rapid movements caused intermittent failures.

Click to expand...

The limit swith should not cause the 103 alarm, but hey, I am sure I have not seen it all.

As others say, I would inspect the cable. An easy test is to disconnect the front Y-Axis cover and jog the y axis all the way to the rear of the machine. Place the machine in E-Stop then you can grab the cable and inspect the outer cover in the area that it flexes for breaks or tears which would indicated a problem with the internal wires. On older cables, the coolant causes the insulation to become very brittle and will crack instead of flex. Then it moves to the internal wires/insualtion until it creates and open circuit, or worse, a short circuit.

If you don't see any visible damage, you can clear the E-Stop, then put the machine in jog mode for X -Axis. Now with the servos on, move the x-Axis cable in the place it normally moves to see if you can recreate the alarm by moving the cable. Be sure to have machine in X-Axis mode so that if it jumps as you described, the machine moves in X and not towards your hand. Only do this if you fee confident doing so. If not, call your dealer and let them stick their hands in the machine. LOL

Safety First Please!!!

Good luck!

haastec said:

The limit swith should not cause the 103 alarm, but hey, I am sure I have not seen it all.

As others say, I would inspect the cable. An easy test is to disconnect the front Y-Axis cover and jog the y axis all the way to the rear of the machine. Place the machine in E-Stop then you can grab the cable and inspect the outer cover in the area that it flexes for breaks or tears which would indicated a problem with the internal wires. On older cables, the coolant causes the insulation to become very brittle and will crack instead of flex. Then it moves to the internal wires/insualtion until it creates and open circuit, or worse, a short circuit.

If you don't see any visible damage, you can clear the E-Stop, then put the machine in jog mode for X -Axis. Now with the servos on, move the x-Axis cable in the place it normally moves to see if you can recreate the alarm by moving the cable. Be sure to have machine in X-Axis mode so that if it jumps as you described, the machine moves in X and not towards your hand. Only do this if you fee confident doing so. If not, call your dealer and let them stick their hands in the machine. LOL

Safety First Please!!!

Good luck!

Click to expand...

Don't recall describing that it jumped.. It would rapid two to three inches then alarms out.. just finished a job running on 25%.. what a pain..
I'm inclined to believe that it's the x-axis cable as all of you have indicated.. when I bought the machine, I noticed while removing the way covers for cleaning and repairing the cover seals, that the outer cabling was broke in three places. so three months ago after reading about some of the problems with this x-axis cable, I pieced them together with some flexable split wiring cover then zipp tied them together in an attempt to get more mileage out of it. seemed to hold together when I rechecked the other day. but as you all have said.. it sounds like i have some work ahead of me. so what's the trick to get the cable through that 90 degree bend? is there a specific process that worked for you?

ok...I misspoke, er typed. I had an almost broken connection on the X axis, I forget the alarm #, would be fine in low rates and fail in high, that I do recall. There is a post on here I recall someone cleverly reworking the hole to gain better access for the cable.

So the cable routes thru a bulkhead 90 deg fitting. What Haas supplies is the cable with the connector(to connect to the machine) and conduit along with a new 90 bulkhead fitting. If you replace the cable, the conduit that runs up under the X axis table should be in good shape as it doesn't see the coolant like the section before the 90 bulkhead fitting. The install is not tough if you have little hands, we normally leave the OG 90 bulkhead fitting in place and then fish the new cabling thru to the motor using a fish tape. Use some liquid soap to help the wires thru the bulkhead fitting as that is the toughest corner to get around. Match the wire colors to the encoder wire colors and your home free.

As BGL said, the axis will jump on you sometimes when there is a bad connection, as it is shorting out or not getting a constant signal. And yes also check the wires for the Y axis limit switch as they ride in the coolant/ waylube mix at the bottom of the base as well.

Good luck,

Just received my New X-axis cable late yesterday.. was already in the process of r/r ing the spindle motor.. (had the motor shop replace the top bearing). Now I've removed all the way covers.. and am now looking at replacing the x-axis cable.. anyone out there got pic's of replacing their cable? the new cable comes with a 45 deg fitting.. looks like i just replace the bottom half of the cable and fish through the wire like sage has indicated. here are some questions I have. do i have to remove the x-axis motor? the electrical box is on the bottom side, can't even imaging trying to get a tool in there to remove the cover plate.. also not sure on the connectors. I may need to get a technition in to assist in this matter... pic's would really help..

Nothing terribly high tech about removing the X axis motor other than awkward position, bad lighting, funky coolant/oil/chip stew. Invest in a pair of spanner wrenches to dissemble the thrust bearing and clean, lube and adjust.

This is an important preventative maintenance step, now is the best time since it is all apart. The thrust bearing is very simple but its weakness is its "open" and the grease over time migrates out. Been faithful for twenty two years, addressing this now will give you twenty two years more!

With the motor removed, before you dissemble the thrust bearing. Get a feel of the rotation of the drive screw drag by rotating it by hand. Set up a dial test indicator on the end of the shaft (finer the better). Hold the screw so it does not rotate and shove the the table both directions to get the total deflection, write it down!
Once reassembled the adjustment is simple, sneak up on it to just about where you feel too much drag when you rotate the drive screw and back out just a bit, tighten the jam nut, recheck... repeat. Once you feel it has no play but spins nicely recheck with the indicator, mine went from 0.0005" to zero as far as I could see and screw felt like it was smoother and spun freer than when I started. I used a drop of Loctite® 290™ once it was set but that's my OCD. I regret not doing this to my Z axis that I had the chance too, sure enough it failed me and cost dearly.

One of the members: STJ7780 has posted a lot of work with pictures. Other than the crappy plastic tub of an enclosure this is still a machine that can make you money.

To gain better access to the motor you can remove the black sheet metal piece that is under the way cover. That should get your wrenches in and out of the tight spots around the motor from the bottom, but you may need a long extension to reach the motor bolts. If your motor as a plug connector you should be able to get the pins and tools at your local Radio Shack so you can put the connector back on the X cable. If not then make sure you solder the connection and wrap it in shrink tube to keep it from shorting. I didn't remove the motor but removed the endcap to the motor. This is where you will find the endcoder and the wire connection that needs to be made with your new cable.

Shorting out is the next step to failure, and then you would see the table start jumping around which is what BGL was describing. If this happens you rick loosing the X board by frying a component or several, all of it being expensive.

As BGL said look up ST7780 thread. He stripped her down to her underwear and did a though cleaning as well as replacing things that were worn or damaged. There's lots of pics there to get an idea of what is under her dress.

We just bought another vintage Haas for our shop and she dropped this past Friday so now my work begins as well.

Good luck and keep us posted.

i did took off the sheet metal pieces like you suggested.. I looked at ST7780's pic's when i relized i could take it off.. that helped. thanks for the suggestions.
X-axis cable is now out. trying to feed a fish tape through the conduit.. hang's up on the 90 deg bend.. not sure what to do here, so i used a vaccum to suck a string through then tie on a .095 weed eater string to fish back though. then tie on the cable, using dishwashing soap tried to pull through.. 5 attempts so far. I keep breaking and or pulling the weed eating string though. any tips on pulling the cable through?

Only thing I got is to try Klein 51010 Wire-Pulling Lubricant. It is more like a wax that stays on the cable unlike soap.

Sometimes you need to push at the same time your pulling, so an extra pair of hands helps.

Fishing it through is the worst part of this job, but it can be done.

I guess I was trying too hard.. Removed the conduit between the x-axis motor and the 90 deg fitting.. was just able to get a wrench in and loosen up the nut.. the fishing the cable was easy after that..
X-axis cable in now in.. test.. same problem.. called the service tech, swapped x to y drive on the board.. turns out its the x-axis amplifier board..
now the spindle motor is acting up.. been a tough day.

Sorry to hear, hope it works out.