New motor: Thermal protection needed, or not?

[Alex Shanku]

Hello,

I am in the process of purchasing a new motor for my jointer. I have found two motors that may fit the bill. Both are Leeson 1hp 1ph 3450rpm motors.

The ONLY difference is one offers no protection, and the other, according to leeson's website offers, manual protection.

Could somebody explain to me which motor would be better for my application, and why?

Also, there is a substantial price difference between the two.

Thanks,

Al

[Tim Morton]

Hello,

I am in the process of purchasing a new motor for my jointer. I have found two motors that may fit the bill. Both are Leeson 1hp 1ph 3450rpm motors.

The ONLY difference is one offers no protection, and the other, according to leeson's website offers, manual protection.

Could somebody explain to me which motor would be better for my application, and why?

Also, there is a substantial price difference between the two.

Thanks,

Al

manual reset is ussually much cheaper....and the only reason not to go that route is if getting to the motor to rest it would be a major hassle....in whihc case with your jointer it is not. Go manual and save the bucks. Any chance you could go a little bigger on the motor? 1.5HP even?

[Alex Shanku]

The price difference between 3/4, 1, and 1.5hp is negligible. However, the jointer was originally powered by a 3/4hp, so I thought moving up to 1hp would suffice. Should I look to go bigger?



Oh yeah, the 1 hp motor without any protection as $75, the motor with manual is $150.

[Tim Morton]

The price difference between 3/4, 1, and 1.5hp is negligible. However, the jointer was originally powered by a 3/4hp, so I thought moving up to 1hp would suffice. Should I look to go bigger?



Oh yeah, the 1 hp motor without any protection as $75, the motor with manual is $150.


Sorry I was reading that you were choosing between two motors one having manual protection and the other auto-reset protection. I would not be qualified to suggest you get a motor without any protection...that would depend on your electrical circuit I think.

As for the motor size...what kind of jointer is it? Maybe others here have first hand experience with replacing the motor.

[Bruce Shiverdecker]

A little information

The circuit breaker protects the Wire running from it, not the equipment.

Having some sort of overload protection is an insurance policy that allows you to know that there is a problem with a motor setup BEFORE it becomes catastrophic. This can be in an auto-reset that will trip when the motor overheats and can be reset when the motor cools down or with overload heater protection in the starting circuit to the motor.

Another thing to look at is the temperature rating of the motor. One that has a higher rating is better than one with a low rating. The physical size of the motor might vary with this rating.............higher rating...........bigger size or at least better made.

Hope this doesn't muddy the waters too much.

Bruce

[Alex Shanku]

Ok guys,

Thanks for the feedback. The jointer is a Powermatic 50 6".

So, definitely need protection. Manual is fine by me. So that leaves the question: What hp? 3/4, 1, or 1.5

I am still leaning toward 1, but am open to suggestions.

I will keep temp. rating in mind, too.

Al

[Frank Hagan]

Hello,

I am in the process of purchasing a new motor for my jointer. I have found two motors that may fit the bill. Both are Leeson 1hp 1ph 3450rpm motors.

The ONLY difference is one offers no protection, and the other, according to leeson's website offers, manual protection.

Could somebody explain to me which motor would be better for my application, and why?

Also, there is a substantial price difference between the two.

Thanks,

Al

I like the TEFC ("totally enclosed fan cooled") motors Leeson has in their "Farm Duty" line. I don't know if they have 3450 RPM motors in that line; I used one of the 1725 RPM motors for my drill press. The enclosed windings help with preventing dust buildup and premature death, and they all come with a manual overload switch if the motor does overheat. A 1 HP runs about $140 from Electric Motor Warehouse or Amazon.com. I know Electric Motor Warehouse also has a line of "woodworking equipment motors," and they do come in TEFC housings and have manual overload protection, but they are a bit pricier.

[Dev Emch]

Why bother?

Three phase motors are always wired through contactor starter units. These have a number of features to consider.

1). This unit switches all three legs into and out of circuit as a single mechanical operation.

2). The pull in coil is single phase and often reduced voltage. You can if you wish use a 24 volt AC starting circuit. Most are about 110 or 120 volts.

3). In the advent of an emergency power cut off, the machine trips out to the off position. This way, you will never have the motor running when power is reconnected.

4). Motor starters feed the juice through an overload relay block prior to feeding your motor. This block may be of an older design which incorporates heaters or a modern design which is a solid state overload relay block with adjustable tripout points. Most of us use heaters and they work great.

So I would personally not change out the motor but if you do, remember you can rewire a three phase heater equiped contactor to work on single phase. Clearly you have to swap out the heaters to reflect the change in current loading but its possible.

So I dont see much point in buying a motor with an internal overload feature.

Good Luck...

[Scott Loven]

Make sure the motor will fit in the space, that the pulleys will line-up etc. before you make the switch to a larger motor. Don't ask me how I know this!
Scott