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#61030 - 01/14/06 07:58 PM Dynamic braking  
grizzly  Offline
Junior Member
Joined: Dec 2005
Posts: 1
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


Work Gear for Electricians and the Trades

#61031 - 01/14/06 08:22 PM Re: Dynamic braking  
deverson  Offline
Member
Joined: Mar 2005
Posts: 20
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


#61032 - 01/18/06 02:55 AM Re: Dynamic braking  
Scott35  Offline

Broom Pusher and
Member
Joined: Oct 2000
Posts: 2,707
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!

#61033 - 01/18/06 04:27 AM Re: Dynamic braking  
Alan Belson  Offline
Member
Joined: Mar 2005
Posts: 1,803
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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