help with mitutoyo 192 height gage

Hi, someone recommended me to this site for some help. We have 24" digital double beam height gage, model 192-657. it is getting a E-05 code if moved to quickly. it is showing .003 backlash against a cadillac gage and blocks. I tried some of the things that were mentioned in other posts. unit is clean, double checked the encoder engagement,seems ok. when i looked at the unit with the gears and spring for backlash spring seems a little loose but I would guess not much tension to start. I was given the idea it could be the encoder? would like to get more feed back first though. thanks for any and all help.

Seth

elmss12 said:

We have 24" digital double beam height gage, model 192-657. it is getting a E-05 code if moved to quickly.

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All position encoders have "speed limits". If you move the sensor faster than that, you'll get an error. This is a universal law in the realm of digital electronics.

If you suspect the unit is actually defective, I recommend sending it to Long Island Indicator Service at www.longislandindicator.com

Although I've never dealt with them myself, they've been highly recommended by innumerable folks, many of whom I know and trust.

- Leigh

Thank you. will try giving them a call.
Seth

All position encoders have "speed limits". If you move the sensor faster than that, you'll get an error. This is a universal law in the realm of digital electronics.

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Not usually the case when these things show the code. As part of my job I work on and calibrate these things regularly. It is uncommon to get the E05 error unless the hite gage has been dropped with sufficient enough force to cause the encoder tensioner gear momentarily loose contact with the rack behind the front beam. The E05 error code in yor case means that the preload has been lost. If you open the unit up you will see 5 screws around the encoder. 2 of them hold the encoder unit together and the other 3 allow you to remove it as a unit. Once removed you will see 2 sets of gears that ride on the back of the front shaft. One is the direct connection to the slotted plate the optics shoot through, the other has a tensioner spring just on top of the gear. The trick is to remove the encoder, rotate the tensioner gear a couple of turns then get it back into the body against the rack without letting the tension off of the spring. You might see a little hole in the front of the slotted plate. This is to put a paper clip in to hold the tensioner gear during reassembly.
It is likely that the hite gage is no longer calibrated since the beam got whacked. Check it against a hite master or a good set of gage blocks. If you find it needs to be adjusted to bring in the calibration to match your master, say the word and I'll steer you onto the easy path.

Just an FYI. If it was working well before the code showed up don't adjust the spindle nut in the center of the encoder. That gets into more advanced adjusting, and I'm tired of typing. Good Luck! -Mike

Hey Mike, thank you that solved the backlash problem and no more code. When checking against our height master I am off .0025 by 6", .003 by 9", but only .0015 at 12"? i read one of your other posts and ran up and down to known good plates, only showing .001 total from bottom to 16" up. When i had the encoder out and looking at it good there are stripping marks on center shaft screw head as if it has been moved before. Also appears as if the spinning and stationary "window discs" are touching. Thank you for helping out. We got this gage not to long ago was working good. Part of my problem is the guy who it broke with won't fess up to anything. He says it was fine, but i used it in morning no problems. Then when i came back in afternoon one of the other guys told me this guy was jumpy and ran out of inpection and wouldn't check any more parts. Kinda tell ya something? Sorry about rant, wish i could fire the guy but father in-law feels bad,knows he wouldn't be able to get another job. Thanks Again
Seth

Glad it worked out for you. Now that my fingers are rested up I'll tell you that the adjustment in the center of the encoder is for setting the spacing between the two slotted discs in the encoder. They shouldn't be touching but will be very close. Adjusting the space sets the timing for the optical reader.

Those are strange numbers you're getting at 6,9,&12", especially with a perp of .001" over 16". If you want to try and get it better I'd suggest a bit more preload on the encoder gear then check your measurements every inch and write them down. It is also important that when you set the encoder back into place in the body that you "listen" to how the gears are meshing as you move the body up and down. It should be smooth and quiet.

We only use 12" models here at work and some of them are from the early '90's. We calibrate them every 6 months unless they get repaired. Ours are able to hold size at every inch or so within 25 microns. Yours should be able to do way better than what you wrote. But if it's good enough... -Mike

Thanks for the great info, Mike.

I made this sticky so folks can find it in the future.

- Leigh

Hi Mike,
The gears are a smooth mesh up and down complete rack. Even removed the hand wheel gear and moved by hand, all good there. The discs were definetly touching. Is there a certain spacing for the discs? Also when i loosened the center screw slightly it appears as the rotating disc has a warp to it, moving to and from encoder aprox. .01-.015 are they supposed to run straight? I appreciate all the help. Thanks

Seth

it appears as the rotating disc has a warp to it, moving to and from encoder aprox. .01-.015

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Ah, that explains the weird non-linear readings. You are lucky to be getting the accuracy you've got.

I have tried straightening the discs before with no luck. You can give it a try if you feel lucky.

If I were you I'd wait a few days. I will look up the part number and the list price of the part you need (shouldn't be too much, IIRC a whole encoder is only $102) and post a source to order the part from. I'll have to get with the guy that orders the parts for contact info.

It isn't likely that the two problems are connected, i.e. the encoder skipping off the rack and the bent serrated disc. More than likely the people you bought it from trashed the disc thinking that moving it would adjust the cal. When they realized it was trashed it hit Ebay. -MIke

Here's a link to the place where we buy our parts. Mitutoyo has a parts warehouse and they drop ship from there most of the time:
http://www.idealprec.com/

Unfortunately the parts breakdown doesn't show individual components of the encoder, so you'd have to get the whole thing. part number is 953861 and is listed on their disc for $102.65. It could be cheaper, many times the parts we get through Ideal are less than list price.

Good luck! -Mike

Hey Mike,
Thanks for all the info. Will be calling them tomorrow. I got this from a local guy downsizing. He admitted he had messed with the screw. For what i got it for well worth the encoder price. My guy finally admitted to dropping it against surface plate, after seeing new price. can't say thanks enough, I like to keep whatever Repairs I can in house. If your ever out this way give a shout, we owe ya one.

Seth