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#61030 - 01/14/06 03:58 PM Dynamic braking
grizzly Offline
Junior Member
Registered: 12/28/05
Posts: 1
Loc: Sanford, NC
I have an old Greenlee table saw that is used to cut aluminum up to one inch, as well as plastic and wood. It operates on three phase, 230 vac and is an old direct drive type. The problem is that it takes a very long time for the saw to coast to a stop. I would like to know if anyone has ever installed a dynamic brake on something like this before?

Regards
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#61031 - 01/14/06 04:22 PM Re: Dynamic braking
deverson Offline
Member
Registered: 03/07/05
Posts: 20
Loc: Mosinee, WI USA
We use a plugging contactor to stop coal shakers within 5 secs. Not the cheapest way as we have to change the contacts on the reverse contactor every 2 years at best. But they get used 500 times/ day, no BS.
We looked into softstart controllers but they didn't do what we wanted. Dynamic braking requires more room for all the associated equipment.
Hope this helps
Dave
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#61032 - 01/17/06 10:55 PM Re: Dynamic braking
Scott35 Offline

Broom Pusher and
Member
Registered: 10/19/00
Posts: 2707
Loc: Anaheim, CA. USA
Grizzly,

Here's a Schematic regarding Dynamic Braking of an AC Induction Motor, which may be of some assitance to you:

Dynamic Braking of AC Induction Motor

The Schematic shows a 3 phase Motor, just edit to include 2 motor Leads rather than 3 Leads.

Also, you will need to have this braking system interlocked with some type of starter. This would be best done within a conveniently sized external cabinet, that contains all needed equipment.

Scott35
_________________________
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
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#61033 - 01/18/06 12:27 AM Re: Dynamic braking
Alan Belson Offline
Member
Registered: 03/23/05
Posts: 1803
Loc: Mayenne N. France
Grizzly, if you fit a brake to this saw, don't use a dado head on it.

Alan
_________________________
Wood work but can't!
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