motor brakes

[HCBFlash]

I'm fighting a couple brakemotors, made in an eastern asia/pacific rim country, and with little documentation available,,, none in any language I can understand. I've worked with/on quite a few motor brakes in the past on NEMA motors, but my memory of the details is poor. Anyone have any good links / urls or other electronic documents pertaining to general repair/adjustments of motor brakes?

This is on a hoist traversing application, integral horsepower.

 

[Laplacian]

http://www.reliance.com/pdf/instruction_manuals/obsolete_inactive/B3661.pdf

?

Reliance also has manuals for other models here:

http://www.reliance.com/literature/literature_main.html

Look in the "manuals" section.

 

[stardelta]

Brake motor design varies greatly, AC or DC versions, even self adjusting. Demag mechanical brakes as people in the industry will confirm are unique in that the motor has a taperd rotor and core. The rotor moves lateraly against a thrust bearing when energised and releases the brake. Some motor manufacturers have their own designs of brake, other buy in and fit brake assemblies made by 3rd parties.
Brakes are not fit-and -forget items, we see many that have failed. I think what is important is that regular checks are made on the brake itself. Things to be aware of are the build-up of dust from the friction material that can prevent free movement and operation, and the monitoring of the airgap and friction disc thickness as it wears. I have also seen a few where the supply leads for the brake have come into contact with moving parts and caused earth faults and O/Cs

 

[powerjunx]

Hi HCBFlash,

StarD, integral Hp is quite large machine employing brake motor is quite complicated. However, when it comes to Demag, i'm hesistant about tapered rotor and core works with integral machine. Although principles applies commonly to all hoisting system in all mechanical aspects.

We have hoisting system utilizes separate braking system we call it "magnetorque motor brake" it is electrically operated so wear and tear is out on the subject.

 

[MikeHalloran]

The (few) hoist traverses that I have worked on had auxiliary manual brake releases (which might also set the running clearance, I'm not sure), spring- set brakes, and the brake release coils were controlled by the traverse motor controller, not a mechanism within the motor.

Perhaps we could be more helpful if you posted the make/model etc from the nameplates.



Mike Halloran
Pembroke Pines, FL, USA

 

[waross]

I have seen designs of electric brakes that would not release if the wear was too great. The braking force would be greatly reduced until the brake operating coil burned out. Then the motor would be dragging the full braking action. The brakes would then often glaze. At this point the decision as to rebuild or replace would depend on what parts were available. Considering the labour to repair an old, overheated, dirty, corroded brake assembly, it was often more economical to replace the entire brake assembly.
respectfully

 

[HCBFlash]

The unit(s) I'm dealing with is by Sumitomo. They are not very much at all like a Reliance / Stearns unit, or my recollection of what a couple CM Hoists that I've dealt with were like. They do NOT have an external brake release. It seems like they have two conical-tip screws that are used to force and hold the brake released. They don't appear to do this very well however, and so my usual method of careful disassembly and re-assembly isn't helping me figure out just how the unit is supposed to be set and adjusted

Please let us all know how this works out for you! and don't forget faq731-376

 

[HCBFlash]

The unit(s) I'm dealing with is by Sumitomo. They are not very much at all like a Reliance / Stearns unit, or my recollection of what a couple CM Hoists that I've dealt with were like. They do NOT have an external brake release. It seems like they have two conical-tip screws that are used to force and hold the brake released. They don't appear to do this very well however, and so my usual method of careful disassembly and re-assembly isn't helping me figure out just how the unit is supposed to be set and adjusted

 

[MikeHalloran]

The wiring diagram and notes on this page:

http://www.sumitomodrive.com.sg/listDownloadsPart1.asp

were not very helpful wrt brake adjustments, but they make the wiring clear enough ... for some Sumitomo brakemotor, not necessarily yours.

Maybe it will lead you to something better.


Mike Halloran
Pembroke Pines, FL, USA