Double poll switch

Discussion in 'Electrical Forum discussion & Blog' started by Giles, Feb 24, 2009.

  1. Giles

    Giles Retired tool & Die and Mechanic

    Messages:
    110
    Location:
    N.W. Alabama--Florence--
    I have an old, probably 1970s, Dewalt 740 radial arm saw. My on-off switch went bad and I was surprised to find out it is a double poll switch. This switch is not available, so I plan to use a double poll switch for replacement. This is 110v application.
    Out of curisoty, why are both the neutral and the hot broken in this application?
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,889
    Location:
    New England
    Most of the motors used on those tools can be rewired to run on 220vac, so you'd then HAVE to break both leads to remove all power. This is done by moving jumpers in the motor assembly, then replacing the plug or power cord.
  3. Giles

    Giles Retired tool & Die and Mechanic

    Messages:
    110
    Location:
    N.W. Alabama--Florence--
    Thanks---I now understand and that makes sense.
  4. Giles

    Giles Retired tool & Die and Mechanic

    Messages:
    110
    Location:
    N.W. Alabama--Florence--
    Upon investigaton for replacing the factory switch with a double poll switch, it was discovered that extensive modification will be necessary for a neat application. A single poll switch would be much simpler. It makes sense to me that a single poll switch could serve the purpose of breaking the hot and I could connect the two neutrals. I know this would not work for 220v.
    Would this be advisable?
  5. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,889
    Location:
    New England
    You'd lose the UL certification. If someone tried to change it to 220vac operation, they could be injured. If it generated a fire or injury, your insurance may not pay. Proceed at your own risk.
  6. Giles

    Giles Retired tool & Die and Mechanic

    Messages:
    110
    Location:
    N.W. Alabama--Florence--
    Thanks, I will use the double poll
  7. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,485
    Location:
    Cave Creek, Arizona
    two pole

    Check the motor plate to see if it is a 120/240 motor. If not then the reason for a two pole switch would be acedemic.
Similar Threads: Double poll
Forum Title Date
Electrical Forum discussion & Blog Can I use 2 single pole 30 amp pushmatic breakers as a double pole set up May 28, 2014
Electrical Forum discussion & Blog Double 14AWG wiring gauge Sep 10, 2012
Electrical Forum discussion & Blog Double Pole Single Throw Switch Jun 4, 2012
Electrical Forum discussion & Blog Double Tap Question Apr 10, 2012
Electrical Forum discussion & Blog SPDT double-throw switch Dec 27, 2010

Share This Page