Home Forums General Discussion Technical Questions Otis Gamma 160 AC Drive problem

I have 2 of these on my route. One is a freight that is hardly used and the other is a passenger. Both identical geared machines with disc brakes. The passenger blows one of its main fuses about every 3-4 months. ($350 fuse) When it happens the car is always found about a foot above the top floor. We have routined all connections in the controller and swapped around the arrangement of the heat sinks mounted in the top of the controller. It has not blown the fuse since. My next problem is that every time you cycle the main line power the elevator instantly tries to run. If the power is cycled with the elevator at the top landing it will put itself into the overhead. Any ideas would be very helpful. Thanks from your IUEC brother.

Been a while since I have seen one of these I have a gamma 160 book buried in my library somewhere, I'll take a look on mon. Start warming them up to a mod because a lot of those parts are not avail and not supported anymore.

you know its bad when your troubleshooting in your sleep. woke up and remembered something. check your tach for loose connections and proper shielding if the voltage produced is wrong it will go into braking mode not motor drive taking your car into the overhead. that will also cause a weird pulsation that will oscillate the drive causing fuses to blow. any complaints for rougher than normal ride? check your B(braking) and M(motor) lights for proper operation.

No complaints of rough or abnormal ride. Have not checked the tach, connections or the voltage. Will check, thanks for the tip. When it happens and blows a fuse it is always first thing in the morning and at the top floor about 1 foot above floor level when I get there. About the other issue when turning on mainline it always wants to run and will go into the overhead if power is restored at the top floor. Any idea to that?

My only guess on that would be check terminal all the terminal switches. Clean contacts and change rollers if marsh mellowed and check the stud that holds the armature on those the weld can break over time. And I'm pretty sure those have a making direction sw contact for floor correction. Good luck.

Forgot to mention that I checked the terminal switches and their contacts and connections. Rollers appered to be ok. Need to check the stud conditions. Thanks

Worked on one today that was acting similar. Turns out someone changed the "BY" relay with a S & S that only has a AC rating on the contacts. The contacts disintegrated and allowed the brake to fry and constantly relevel. The main fuses blew. Since the brake was hot it was drifting up. Changed the relay and fuses and all good. Had to adjust the Hilliard brake too.

you say the car instantly tries to run when you turn on the power, what does the car do when you turn off at the bottom floor? does the car immediately run to the next floor and return to service, or does it start in the up direction and stop between floors and then do a regular run???? one thing to check is to see if the car tries to run before the 24R led is illuminated. when you power the car on, after a few seconds the 24r led will illuminate if the phases are in correct sequence. when the car runs up, is the UX led illuminated, or is the DX led illuminated?

Will watch the relays when power up. It acts normal when you turn off the power. The BY and BW relays are the factory ones and I have taken them apart and all seems ok. This has a Ogura disc brake that I know nothing about. Dont think it has any problem, but they are no help and said it is proprietary to OTIS.

Swapped the "SB" board in the Gamma 160 drive with that of a good one from the freight elevator. That resolved the issue with the elevator wanting to instantely run when the power is turned on at the disconnect. Ordered a board from Unitec. (obsolete but they had one)Hope that this takes care of the other trouble calls that shuts down the unit either in the overhead or below the bottom floor. By the way this is a MRV controller.

MRV= mid rise value
MRVF= mother beep beep [censored]
Glad you got it goin. Tell the customer that was the last part in existence so they think about mod or know the next time it's down it could be for a while.

I worked on a couple of these units about 15 years ago, I thought they were obsolete then, was surprised to see this controller still in existence. If I remember right this controller has a timed slowdown ramp starting at slowdown point in hoistway, it decels until timed ramp ends and then it will stop. I could be wrong but I remember tring to set floor levels when we first got the job thinking that I could just move level sensors but that didn't work, had to adjust drive and make sure slowdown distances were equal for all floors, try making the car run without stepping and see what happens on a terminal slowdown, see if it runs over. Also I seem to remember if car was off level, after a certain time delay the car would relevel to level sensor adjustment. I'm with green pants on this one a mod is way over due

Thanks for the advice. I wish our customer understood this.

We actually got a 2 of these boards lying around the shop somewhere. We got to pick apart a few controllers in the Constellation hotel, Toronto, before they started to rip it down.

Good to know they were worth keeping....

you could probably get a good price for them if you sent them into OSC for repair.

Nice. We just walked out with them too lol. The place was abandoned but they only needed one running so we took what we could and still made a pretty penny on the maintenance contract.

MRVF had alot of these babies. Batteries to run an elevator. wow. They ran good for me though once i changed the selector and learned to keep the load weighing adjusted properly. Usually only one or two calls a year

hi
any one has knowledge of otis ovf30 fault codes
i have a ovf30 vfd displaying fault !040
can anyone explain the fault
thanks