I work on very big VGT's

[Wildcard]

(07-04-2021 )Rawze Wrote:  Why is there a chunk of crud on that roller inside that bearing?


And WHY is that not a sealed bearing? - is there lube flowing thru the housing?. ... What RPM is it turning? ... and what viscosity oil is that bearing running on?.

I worked on, and helped design various types of industrial machinery like that for many years. that thing also looks like a permanent magnet DC? or a reluctance motor?. can be hard to tell just from a picture.

Also, is there a Tach-feedback on the motor to close-loop that VSD?.. or is it open loop and the VSD has no idea (guesses at) what rpm the thing is at? - I see that mistake a lot in industry with big DC drives like that ... Damned engineer who designs it don;t think it needs motor feed-back and then there are problems with surging, etc, later on.

-- ALSO... What type of dynamic braking system does it have on it?... and what brand/type of VSD is on it?... and how old? .. and Is that VSD protected with and a line-reactor and Amptraps (specialized solid-state fuses) on its front-end properly?

all the programming in the world will not make up for properly.. a poorly designed system.

The chunk of crud is actually a chunk of metal missing. It's Bearing Spalling. Trane had and issue with some Timken bearings doing this due to the oiler orphis for that bearing not being big enough. It's an oiled bearing.

These compressors spin max 3600rpm but depends on design and application. Every chiller is purpose built be it for comfort cooling or a process application.

No tach feedback, it's just a WAG from programming motor parameters and motor speed at 60hz.

The York machines are fairly complicated and way over engineered for typical comfort cooling applications in my eyes, Yorks market share is Govt/Military and Ship cooling. So everything they build is to those specs. I can't really stand being near them when they are running as they have a rumble/noise that makes me feel like I need to throw up.