Replies

1. 
   TKanzler | Jun 18, 2002 09:24pm | #1

   If the wiring is adequate for the load, it makes no difference to the motor.  The windings are in series or parallel, depending on line voltage, and therefore each winding sees the same voltage and current.  This has been discussed a lot in the past.  See the following thread, for instance.  <Incorrect link deleted - see below> If you have an inductive ammeter, check the amperage drawn against the nameplate amperage (FLA).  Make sure the blast gates are open, otherwise you won't be putting full load on the motor.  If the current is less than or equal to FLA, it's fine.  Nothing to be gained by reconfiguring.  You can also check the voltage across the line terminals in the motor (not in the panel) while it's running.  The closer to 115V (motor nameplate voltage) under load the better.  And besides, the higher voltage requires a double-pole breaker and switch, different plugs and receptacles, etc.  If it's running within specs, leave it.  At least, that's what I'd do.

   Edit: Deleted incorrect link

   Be seeing you...

   
   

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   Edited 6/19/2002 7:35:08 PM ET by TDKPE

2. 
   sschefer | Jun 18, 2002 10:12pm | #2

   Only one thing will change with 230. This is the current rise time. Since the motor now has two current sources rather than just one, the current requirement on each leg of a 230v circuit should be 1/2 that of the single leg of a 115v circuit. The rise time to required starting amperage should also be 1/2 which means the motor should start faster and produce less heat. During a no load situation the heat will be the same since the current requirement of the motor never changes in the no load state. In a load condition, when more current is required, the rise time to the new current requirement will also be shorter. Because it is shorter the motor might bog for shorter periods of time but it will not produce anymore power.

   So is 230v better than 115v. I think it is in the long run but it does require you to make changes to your equipment and makes them much less portable if you need to travel with them at all. 115v is much more universal in the U.S. 

   Steve - in Northern California

   
   

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   Edited 6/18/2002 3:13:06 PM ET by Steve Schefer

   
   

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   Edited 6/18/2002 3:16:47 PM ET by Steve Schefer

3. 
   mitch | Jun 19, 2002 03:48am | #3

   I've rewired a few pieces of equipment from 115v to 230v-

        on my fairly big, 3/4hp, drill press it made no noticeable difference-

        on my 2hp tablesaw it was like it had a new motor!!! ZERO lag in start-up- much less tendency to bog in a cut- a surprisingly big difference!  Quieter, too.

        on my 5hp (peak), 30 gal compressor, it made a significant difference- much stronger, especially at the end of the pressurization cycle with more positive shut-off.  on 115v it would struggle to reach shut-off pressure- which was annoying to hear and probably not good for the machine, either.

        as a dust collector really doesn't have a big load or peak resistance to overcome, it might not have a big effect- but it certainly won't hurt to try it?!

   mitch

4. 
   LRutherfor1 | Jun 19, 2002 04:10am | #4

   Voltage and amperage are inversely proportional.  If you increase the voltage, you decrease the amperage by the same percentage, ie: 115 volts @ 15 amps rewired to 230 Volts would equal 7 1/2 amps.  Check the name plate on the motor and you'll see what I mean.

   When you change the input voltage (115 to 230), make sure that you reconfigure the wires in the box attached to the motor.  It should show you the proper wiring method.  If not, check your service manual.

   Just think, I had to go through four years of electrical apprenticeship to learn this, and you just went to Knots.....not fair.

   Good Luck, Len (Len's Custom Woodworking)

1. 
   sschefer | Jun 19, 2002 07:23am | #6

   Len, are you sure?Steve - in Northern California

1. 
   gerry001 | Jun 19, 2002 02:32pm | #7

   Steve,

   I'll agree with Len on that.

   Gerry

2. 
   LRutherfor1 | Jun 19, 2002 07:06pm | #9

   It's not an exact science, but that's "Ohm's Law".  

5. 
   gerry001 | Jun 19, 2002 07:05am | #5

   The only practical difference is in the voltage drop in the feed, as switching to 230v will reduce the current in half. The total power is otherwise the same. If you're running #12 wire and about 20 feet from the branch, it won't matter. However, if you've got 60 feet of wire, the reduced current from running with 230v will reduce the drop in the wire.

   With a voltmeter you can measure the voltage at the motor, and see the drop when you turn it on. With a long feed wire and 115v, you'll see more of a drop both when you first turn it on, and when it's running. If this is only a few volts when running, don't worry about it. If it's much more than that, it will start slower and run hotter. How much so depends on the wire length and the motor's current draw.

   With some tools like a drill press, the load current changes very little. However, with a table saw, it's more important as the load current may be 3-4 times higher than with no load.

   Gerry

1. 
   sschefer | Jun 19, 2002 05:31pm | #8

   Gerry, Len, whoops, I was reading sideway's again. Len is correct...Well, thats if someone finally proves electron theory. LOLSteve - in Northern California

6. 
   sschefer | Jun 19, 2002 08:15pm | #10

   I'll bet this person can give you some additional insight:

   mailto:[email protected]

   Steve - in Northern California

7. 
   TKanzler | Jun 20, 2002 02:31am | #11

   I gave you a bad link above.  Try this:

   http://forums.taunton.com/tp-knots/messages?msg=6170.24

    

   Be seeing you...

1. 
   mbiker1999 | Jun 21, 2002 03:16am | #12

   Thanks for the advice everyone.  I've only got about a 35' run so I decided on leaving the DC at 115volts and run a 12/2 dedicated circuit to it.  I can always convert it to 230 later, but I don't think I'll need it.

   Since I'm kind of new at the woodworking thing I appreciate all the great replys to us newbies.  I know it must be frustrating sometimes to get the same questions again and again.  I'm learning a lot here from all of you!

   Thanks again,

   Bill

1. 
   sschefer | Jun 21, 2002 05:12pm | #13

   Bill, just as a side comment, I have the Jet 1100 DC. It starts at 11.1 amps and runs at 5.5 so I just left it at 110 and put it on the 15amp circuit that the gararge door opener is on. The shop tools run on a separate 20amp circuit and normally there is only one thing running at a time, (one man shop). As of this writting, I've not had any problems with this configuration. Steve - in Northern California