Replies

1. 
   Stuart | Oct 01, 2005 03:28am | #1

   Delta has a copy of the owner's manual on their website.  It doesn't say specifically what plug they use, but they do have an illustration of it, and it looks like it mates to a NEMA 6-30R receptacle.

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1. 
   TKanzler | Oct 01, 2005 05:03am | #2

   They used to come with a 6-15P plug, which is 15A 250V.  The saw is rated for 12.4A with the 3 hp Marathon, and I believe 12.0A for the WEG.  A 6-15 looks like the 6-30 pictured above, but it's smaller.  It will fit a 15 or 20A 250V receptacle.Be seeing you...

1. 
   Stuart | Oct 01, 2005 05:26am | #3

   You're right, it could be a NEMA 6-20R.  I looked at the Delta online owner's manual again, and they say it requires a 20 amp circuit so that would make sense.

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   However, I wonder if this is one of those 'advertised' horsepower ratings instead of actual...according to the NEC, a 3hp, 230vac motor has a full load amp rating of 17 amps, which is a little too close for comfort.  A 2hp motor has a FLA of 12 amps.

1. 
   TKanzler | Oct 01, 2005 06:05am | #4

   The 17A in NEC Table 430-148 is for sizing the branch circuit conductors.  The NEC requires you to use these values instead of actual nameplate values so that in the likely event a motor will have to be replaced, the new one will have a different full-load current rating, even though it is of the same hp rating.  Overload and overcurrent protection in the motor control is sized per the actual motor nameplate, but the conductors are required to be sized per the Table.  I doubt many on this or other wood forum actually do that, but in industry, all the electricians want to know is "what's the motor hp?" - they size the overload heaters after it's installed.

   The Marathon and WEG motors used in the Unisaws have run capacitors, which greatly reduce the current draw by increasing the power factor, and somewhat increasing the efficiency.  Typical PF for a small motor is in the 80%+ range, and efficiency is in the 70's to 80's, but the Marathon Unisaw motor has a PF of 0.98, and an efficiency of 0.80.  The WEG has similar numbers.  Plug them into HP = (A x V x PF x Eff)/746 and you get 3.0 hp (use the actual nameplate voltage, which is 230V). 

   The Baldor Unisaw motor has a PF of 0.87, and an efficiency of 0.72, for full-load amps of 15.5.  Some of the Asian motors, like Grizzly, actually draw a little more than 17A at full load, or so I've been told. 

   So the Marathons and WEGs are rated properly, and they will deliver 3 hp continously without overheating.  That's why they can use a 15A plug and 14 gauge cord.

   p.s. I have the motor certification data sheet for that Marathon somewhere in my files.  Marathon, like all the other major domestic motor builders, can't and don't fudge the hp numbers.  It's the marketing people who put overstated stickers all over the tools.  The motor nameplates either state the rated hp, or say "special" or "sp" if the tool manufacturer doesn't want you to know what it really is.  Be seeing you...

2. 
   mudman | Oct 01, 2005 10:40am | #5

   That is the recepticle my Unisaw uses.

   Mike

1. 
   SRVela | Oct 01, 2005 09:52pm | #6

   Thanks a lot, folks.  The on-line Delta manual was a little ambiguous on this, so I thought I'd ask the experts.

   UPDATE 10/5/05:  The saw arrived with a 6-15 plug as noted above.  Thanks again for all of your responses.

    

   Edited 10/5/2005 1:11 pm ET by SRVela

2. 
   John_D | Oct 05, 2005 08:15am | #7

   It's neither expensive nor difficult to re-plug your saw.  Consider switching to a L6-20R.  The L is for "locking", but you won't want to do it if you're likely to trip over the cord.

3. 
   scooter1 | Oct 05, 2005 08:17pm | #8

   The cord is stupidly short, and I would replace it.I'd have your electrician install a 3 conductor "twist lock" female plug, and then buy a couple for yourself and re-wire the Unisaw with a nice long like 15 feet) 10 guage 3 conductor cable with of course a twist lock male connector.Regards, Scooter"I may be drunk, but you're crazy, and I'll be sober tomorrow." WC Fields, "Its a Gift" 1934

2. 
   mtburton | Oct 05, 2005 08:41pm | #9

   It doesn't matter.  Put in what ever is code for your area and just change the plug when you get the saw.   My Unisaw came with a plug like the one in message 4.  But ut us easy to chabge out.

    

   Michael