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Got Questions Get Answers => Electrical and Electronic => Topic started by: AllenBolt on December 18, 2015, 04:25:AM

Title: How do I Use Field Weakening?
Post by: AllenBolt on December 18, 2015, 04:25:AM
Hello everybody,
How do I use field weakening on a drive/motor combo. I need to go way beyond the rated RPM of the motor and I was told I can do this by using field weakening on the drive. it is an older Reliance drive and there are settings for field weakening, I'm just not sure what has to be done.

thanks!
Title: Re: How do I Use Field Weakening?
Post by: Cheller on December 19, 2015, 04:59:PM
You need to weaken the field to exceed the base speed of the motor I'll assume. So you need to field the field weakening settings in your menu and enable it. The only other tip I could give you is that you'll need to adjust the minimum field current setting somewhere in the drive parameters. This is how you "weaken the field".

You should also consult the motor manufacturer, shoot them an email or call a rep to determine just how far you can go with the minimum field current setting. Going too far could cause flashover in the motor. It is sometimes called sparking and I'm not sure of the official explanation for flashover or sparking but I know it's bad news...

You also don't want to overspeed your bearings either so it is important to know how fast the motor can safely move.

Good luck with your field weakening.