Home Forums General Discussion Technical Questions TAC 50-04 UIM

Hey Guys,
I have some TAC 50-04's with tape selectors, quite often these units go out on Unintended Motion faults. I am wondering if someone else has been or knows of someone who has been fighting this problem on the tape selector jobs. The 50-04's I have with encoders,transducers and veins work fine but the tape selector job just isn't right. Any info would help. Work Safe.

Take a look at the position encoder speed while the car is at a floor and not moving. If the speed is going up and down you have a noise issue. Check for ac voltage on some of your traveling cable spares. Disconnect the shields on pa, pa-, pb and pb- and see if it goes away. If it does you have a bad ground.

Thanks as722 and your absolutly right, unfourtunately I have been down that road. This happens on 4 duplex banks scattered around the complex but never on the simplex unit, we compared the simplex to the duplex and everything is the same with regards to noise and grounding. No noise and building ground is perfect and bonding perfect. There is no direction, demand or velocity when it happens. Never have entrapments when it happens.

Is unintended motion fault the only fault when this happens, or do other faults happen with same time stamp.

Same faults on all UIM shutdowns, 1904,1655 and 1030.
1904- Detection of unintended motion
1655- RGOK signal dropped
1030- DLB/DLT active at same time.

Governor rope jumping up and down at releasing carrier on stopping is another cause of UIM

Sorry I guess I wasn't paying attention when you said you have tape selector instead of governor encoder. At any rate another thing to check is brake set properly and reader head tape guides worn or dirty selector head sensors

Is it 16 bit or 32 bit controller, might consider checking software version and see if its the latest greatest just something to check.

Are you getting a red fault led on the drive when it happens ? Is it a 16 bit ?

Hey Rick, brake is good and selector and tape clean, selector boards have been updated to latest revisions. And Oleeightball, this has a CPUA (32 bit) board, generic software has ben updated about two months ago. AS722, no drive faults are present. This has gone on since the mod installation, an engineer has been out and is comming back out soon. I have found out they have taken off the tape selectors and installed veins on a couple of units in Colorado for the same reason and that this is not an isolated case. I wonder how many guys have fought this? Work Safe everyone.