Do you leave your D/C running ???

[Dewey Torres]

Ah Ha!!! I knew it!

Go ahead and revisit that remote idea I posted above. Now that we have the facts. Heck, 6 times off and on per hour is once every ten minutes without fail. You may achieve that once in a while but probably not often so who cares. I bet that switch is a cheap fix anyway so load up those country tune and let r' rip!

[Carl Babel]

Shampoo instructions tell you to wash rinse and repeat!!! Who does that?

You mean you don't? I suppose the next thing you're going to tell us is that you rip the labels off of those mattresses, too.

[Sonny Edmonds]

Dewey, I worte you a very elongated reply last night.
Maybe too long.
Because when I tried to post it, IE froze up and couldn't find the web site.
No bother though, why drag a dead cow around.

I know more than I care to remember about electicity and industrial motors, circuit design and maintenance.
You name it, I've had my fingers in it or my electrical brain wrapped around it in some way.
Just know that a motor can be beaten to death by the operator.
Usually the engineer designing the process or circuitry will take into consideration the duty and how severe it may be.
If Onieda (just for example) sez no more than 6 starts per hour, and someone beats their DC to death (those of us who maintain motors and have repaired them can tell) they might replace one. But asking for more is eventually going to raise a bigger stink than the smoked motor.
There is a lot more I could impart about motors, but what the hell?

[Bruce Page]

Shampoo instructions tell you to wash rinse and repeat!!! Who does that?

OMG, you don't?

I turn my DC on & off as needed.

[Dan Friedrichs]

The heat in the rotor bars can actually melt the aluminum, causing an open bar. It's all downhill from there as the motor is now permanently missing a rotor bar.

regards, Rod.

Rod, I ask this in all seriousness: Have you ever seen a sub-5HP induction motor that has gotten hot enough to melt a rotor bar? I'm curious - I've never seen it at all, but I agree that it's possible. I think it's much more likely in a very large motor that's been stalled, though. Also, I somewhat doubt that a motor of this size would have a Al squirrel cage rotor - I imagine it's more likely to be copper windings on the rotor, as well.

[Bruce Wrenn]

[quote=Jim Eller;1019634]I went right to the horse's mouth and asked them.

Single phase motors use a combination of a start capacitor with a centrifugal switch. Turning the motor on and off sends the locked rotor inrush across the contacts of the centrifugal switch, doing so multiple times in a short period of time will eventually cause the switch to fail. Start switch is OPEN when motor is running. It only closes after motor drops in speed. It's a centrifical (sp?) switch, and opens upon motor reaching a predetermined speed, generally less than full speed. The start capacitor can only stand so many in rushes per hour though. The better the capacitor, the more starts per hour. Look at the compressor on your AC / heat pump. How many starts per hour does it do?

[Jim Kountz]

Wow.........Can we beat this horse anymore, the poor thing is dead already folks.......I think if Edison himself replied to this thread someone would still disagree with him....
For what its worth heres some advice from ol Jim.
Do what ever turns you (or your motor) on.

[Dewey Torres]

Dewey, I worte you a very elongated reply last night.
Maybe too long.
Because when I tried to post it, IE froze up and couldn't find the web site.
No bother though, why drag a dead cow around.

I know more than I care to remember about ...

Sonny,
Thank you very much for not posting your "elongated reply".
Every tool in our shops can be beaten to death by the operator. If you give a rat enough red m&m's it will cause cancer. I think you get my point.

All Rick wants to do is listen to his country music in between cuts. According to "the horses mouth" He should be able to do that without worrying about his motor.

We beat this thing to death ... hey, even YOU SAID SO!

PS. I know you are a diver but I am not so where the heck is Saugus, Kelpafornia? I thought you had to put where you actually live when you registered Maybe I am wrong. It has been a while since I registered so I forget.

[Bruce Page]

Wow.........Can we beat this horse anymore, the poor thing is dead already folks.......I think if Edison himself replied to this thread someone would still disagree with him....
For what its worth heres some advice from ol Jim.
Do what ever turns you (or your motor) on.

It seems like a legitimate question with good information to me.
Isn't that why we're here?

[Dewey Torres]

It seems like a legitimate question with good information to me.
Isn't that why we're here?

thread steal on...
Hey Bruce...new avatar. Very nice...can I ask why? It's the second one in a month or so.

thread steal off...

Sorry Rick

[Chris True]

Sonny,
How about you explain to a Southerner What the difference in start up load is between a plenum air fan and a band saw with a blade a two big wheels. I may be an idiot to some but I am (not bragging just credentials) a US Navy graduate in the advanced electronic field and fully understand ohms law, special circuits, resistance, power, voltage, amperage, induction, alternating and direct current, propagation.... yada yada yada... and these are just what I call the basics. I also understand electronic physics to an extent.

Even still... don't buy it. And I am still not sure why Maybe I am dumber than I think.

Bandsaw has inertia but no load on startup - unless you start to cut wood before it reaches speed. The DC has the inertia but also the air load it's designed to run at. That load starts low but keeps getting higher and higher until the motor reaches it running RPM and the full load at the same time.

[Dewey Torres]

Bandsaw has inertia but no load on startup - unless you start to cut wood before it reaches speed. The DC has the inertia but also the air load it's designed to run at. That load starts low but keeps getting higher and higher until the motor reaches it running RPM and the full load at the same time.

hmmm.... I guess that makes since but seems a negligible difference.
Anyway, the manufacturer already answered and stated it has nothing at all to do with our hunches. It's the switch. Thanks for the reply Chris. A short one too. I like that.

[Bruce Page]

thread steal on...
Hey Bruce...new avatar. Very nice...can I ask why? It's the second one in a month or so.

thread steal off...

Sorry Rick

No reason, just an eagle shot from Kodiak.

[Sonny Edmonds]

North of L.A. a bit off of Interstate 5.
Ever hear of an amusement park called Magic Mountain? (A Six Flags Park)
I can see their fireworks from my winder.
My Mom always said I lived on the edge of where ever I was. So I'm close to the mountains, but still close enough to walk to the 7-11 to get beer.
California is known for it's kelp forests in the ocean. So me being me, I coined Kelpafornia for the State I come from, and yep, took up scuba diving.
(The Governor calls it Kally-fornia with his Austrian accent. Sounds like Cauliflower.)
We have a nephew who is a diving instructor who got me certified to dive.
California water is cold though, so it requires a lot of gear and a heavy wetsuit.
Whole different world under the sea. Beautiful world! But I'm almost too old to do the gear anymore. Done wore out parts too soon, dang it!
I'd be proud to buy you a beer and sit and jaw about things if we ever got the chance. We could chew on jerky from dead cows.

[Chip Lindley]

All cynicism aside, turning on your DC 5 or 6 times per hour gives a duty cycle of 12 or 10 minutes (or less). I can certainly see heat build-up in the motor, with many start cycles and little time to *just run* and cool down. But, in my most likely planing/joining/shaping/sawing sessions, my duty cycle is more like most of an hour, once I have my work laid out. I do believe someone would have to be very OCD to flip the switch every 10 or 12 minutes!! Of course, those handy dandy remotes do make it much easier.

On a monetary note, those power surges at FLA will all add up on your electric bill. Starting a 2 or 3 or 5hp induction motor repeatedly uses lotsa JUICE, compared to just letting it RUN!