Home Forums General Discussion Technical Questions TMS 500

God,I love my job.

Over the weekend,had a TMS 500 go down.
The guy troubleshooting it found a bad scr,replaced it.
Trying to run the car on inspect. the motor makes a loud rumbling noise,just barely moves and things start smoking.

I get there,there is a chainfall on top the car because the repair team thought maybe it was set on safeties.
They can't budge the car.
Waiting for me is a huge a-frame because they are going to replace the motor.
This has 5 connections to the motor,,u,v,and w 1 and 2.
I measure the voltage coming from each scr when we try to run it.
I get 109,79,109.

Waiting on a new contactor and new scr's.
Hoping that fixes it.

Could one of the fields be bad in the motor or a bad drive board?

If you lost an SCR you need to make sure that you do not have any AC in your loop circuit. When you run the car on insp or try to that is, measure with you meter on the loop circuit looking for any AC voltage. If you do have any appreciable amount check your ripple filter. Check the fields and armature separately for grounds and that they have the proper resistance. Look for loose connections in the entire loop circuit. Also check the brushes in your tacho's. Baring all these you may have pooped a drive. Since you lost an SCR you may have many other issues unfortunately.

An easy way to check your feilds is to unhook them from the controller and then use machine room 110vac to power them up. Then take voltage reading across each feild. If you have a 4 pole motor you should read about a 30 volt drop across each feild. A six pole motor about 20vac drop. On gearless jobs you will be able to test at the lugs. On smaller motors we will use large neddles and poke the thru the wires. If you have a shorted feild it will read a much lower voltage drop.

Replaced the contactor ,and the IGBT's.

I have four boards attached to each scr,the fourth one is attached to to scr's.
There are 5 scr's.
The last one attached to two scr's ,led lights briefly,but goes out.
But that is not the one I am measuring lower voltage.

Those boards driving the scr's are controlled by a controller board and a firing board which are seated in a mother board.

Replaced the firing board,but not the other two set beings that the controller board has 8 or nine pots on it to adjust speed,decel and acel.

Waiting on the tech.manual on this.
It is called 384,the drive that is.
Why 5 connections?
Why 5 scr's?

Is this the same elevator?

http://www.vatortrader.com/forums/ubbthreads.php?ubb=showflat&Number=4330

Just found out it's a TAC 5.
The motor has a high speed winding and low speed winding.
The low speed is used for braking torque.

Both controlled by a thyristor bridge.

Just got done reading 35 pages of this manual,and they should have thrown in a monkey throwing poop at you to make just a little more complicated.

JEEZ!!!