Longevity of 120V- vs. 240V-wired motor?

  • Thread starter GregJ7
  • Start date
  • #1
4
2
Summary:
Wire motor for 120V or 240V?
The 2hp dual-capacitor motor on my bandsaw can be wired for either 220V (draws up to 10 amps) or 110V (draws up to 20 amps). I need to install a new circuit whichever I decide (30 amp circuit for the 110V configuration). Am I correct in assuming the performance of the motor, such as amount of torque in generates, would be the same whichever way I wire it? Is the theoretical longevity of the motor also the same?
 

Answers and Replies

  • #2
DaveE
Science Advisor
Gold Member
1,740
1,378
Honestly, for a specific motor (i.e. one that's already been designed and built), I don't think it matters. I might choose 240 for lower current in the walls, plugs, etc., but that has nothing to do with the motor. There are subtle differences between series and parallel connected windings, but it's the bearings that will probably kill your motor, not the windings.
 
  • Like
Likes russ_watters and GregJ7
  • #3
anorlunda
Staff Emeritus
Insights Author
9,765
6,859
I think the longevity of a motor depends more on (a) mechanical strength and absence of vibrations, (b) effectiveness of aging insulation, and (c) the ability of the windings to resist shifting in their mounts.

As a teen, I worked in an amusement park. The roller coaster had a 4HP motor built around the year 1900. It was about 9 feet high and weighed several tons. It ran at 180 RPM (maybe 360). The only maintenance it ever had was a few drops of oil every year. It would be 120 years old today, and it could probably continue another 120 years.
 
  • #4
13
0
Summary:: Wire motor for 120V or 240V?

The 2hp dual-capacitor motor on my bandsaw can be wired for either 220V (draws up to 10 amps) or 110V (draws up to 20 amps). I need to install a new circuit whichever I decide (30 amp circuit for the 110V configuration). Am I correct in assuming the performance of the motor, such as amount of torque in generates, would be the same whichever way I wire it? Is the theoretical longevity of the motor also the same?
I agree with Dave,

The 240V connection will draw less current which could mean lower losses, however it really depends on what you have available. If the motor is designed for 120 or 240, then either will work. I also agree that the bearings would be the first thing to wear out before windings do.
 
  • #5
314
240
You may be creating a false choice for yourself. Although your saw has a 2 HP motor, it won't necessarily operate at anything like that power level - depends on blade loading. Unless you are going to seriously load the saw, you might consider just using it with an existing outlet. You'll know that approach won't work if the breaker trips too often.

Use a short (or heavy, or both) power cord to minimize voltage drop / motor heating (whatever you do).
 
  • #6
636
314
The caps will die long before the bearings, which will die long before the windings.

Make sure the caps are suitably rated if you go for the higher voltage.
 

Related Threads on Longevity of 120V- vs. 240V-wired motor?

Replies
2
Views
11K
Replies
1
Views
977
Replies
3
Views
5K
Replies
19
Views
20K
Replies
4
Views
3K
Replies
1
Views
2K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
5
Views
25K
  • Last Post
Replies
7
Views
1K
Top