Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations JAE on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

What is minimum motor length cable to install a pure sine wave filter at the output of VSD? 1

Status
Not open for further replies.

SA07

Electrical
Joined
Feb 22, 2018
Messages
375
Location
MU
Hi

Can you please confirm the minimum length of cable?
 
It us not a standard distance value, it varies from drive manufacturer to manufacturer because it depends on the firing algorithm of their IGBTs and it will also depend on the insulation rating (voltage) of the motor, the type of cable used and the carrier frequency you are using. So the question must be asked of Schneider.

Rockwell publishes their TESTED length data in an installation guide, but it ONLY applies to THEIR drives. For their equivalent drive for a 250kW 400V motor, the max. distance with "no solution", meaning no load reactor or DV/DT filter, is 1,000ft (305M) if the motor has 1600V insulation and the carrier frequency is set to 2kHz (page 129 of that document). But even if the motor had only 1200V insulation, it would still be 129M max. with no filter, load reactor etc.

But that means NOTHING with regard to a Schneider drive. Only they can answer this question.

All that said, your pictures do appear to show corona discharge damage in the windings.



" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
What is the cause of corona discharge damage in the winding? How can we preven this from happening?
 
What is the cause of corona discharge damage in the winding? How can we preven this from happening?
Cause; too high a voltage gradient, possibly ringing excited by PWM switching.
Prevention; filtering.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
Hi
Can you please give me some suppliers for Series A sine wave filter ?
 
TCI, MTE, Schaffner are the biggest. Many of the others that you see are brand-labeled from one of these.



" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
Thanks jraef
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top