The car runs perfectly but gives a loud frequency noise when leveling into or leaving any floor. The motor was rewound after field was cooked. Now we don't loose the Amp Traps but the noise is still to loud to operate the car. Switched the removable portions of the drive from a car next door no improvment. The boards work well in the other car. Any suggestions?

-- Sheldon Anderson (shel@sterlingelevator.com), January 09, 2003

Answers

S6R

I'm not familiar with S6R but I did just have same problem with a Haughton car (exactly the same)and it turned out to be a shorted SCR.Got new SCR's and noise gone.

-- Schindlertech (vze2hpxt@verizon.net), January 09, 2003.

S6R (SCR) Drive noisy

Sheldon, There is (or should be)a very large choke in series with the drive and motor. If you had fields going bad you were probably drawing excessive armature current and it's possible the choke shorted. That choke suppresses exactly the noise you are describing. Some systems also have a bank of capacitors paralleled with this choke. Happy hunting, Fred

-- Fred (Elman101@pacbell.net), January 10, 2003.

Noisy motors and things.

Usually, there is a box which contains a choke, as well as a resistor (usually high wattage) connected to a group of capacitors. The capacitor circuit usually has a fuse. Check these to be sure they are working properly. Based on what you said it might be that the caps might have shorted out or are improperly adjusted (too much cap can smoke things as well as a shorted cap). According to what I understand from montgomery and MCE's info., it would appear that too little cap series resistance will cause the motor to be loud, and too much will result in overheating. Another possability could be that the scr's aren't firing when they're supposed to (either due to an open SCR, or a slow-firing or shorted one), causing quite a problem. Basically, you're hitting a low-ohm coil (the armature) with a 180 Hz pulse DC waveform, and depending on the filtration (caps and choke), the reflected current could cause quite a bit of havoc. Tight power feeders from the mainline, through the transformer, and to the motor are a must with any 6-pulse SCR drive. Good luck!

-- Steve (eastlion@pacbell.net), April 24, 2003.

check the wiring going to the trans and choke. there should be a fuse in the assemble not easy to see.s6r was used by haughton elevator on thew gold flite controls. good system.

-- ricky gonzales (rickygonzales@cox.net), July 27, 2003.