Motor Questions

derekdarling · Post by **derekdarling** » Sun Mar 28, 2010 12:56 am

I have a (new to me) Mark V, and I'm beginning the refurb process. When I plugged it in and turned it on, it would run up to speed, then blow the breaker (15Amp). I have removed the belt and tried again, and the motor runs under no load and does not blow the breakers.

Am I right in assuming that if I give the rest of the drive train a really good clean and lube (which was the plan all along anyway), that this might solve the breaker-tripping issue?

Other than your help, assistance and advice, my next test will be in a couple of weeks when I have cleaned/lubed and reassembled the headstock (following the amazing advice on this forum).

AtDhVaAnNkCsE

Derek Darling

JPG · Post by **JPG** » Sun Mar 28, 2010 1:28 am

derekdarling wrote:I have a (new to me) Mark V, and I'm beginning the refurb process. When I plugged it in and turned it on, it would run up to speed, then blow the breaker (15Amp). I have removed the belt and tried again, and the motor runs under no load and does not blow the breakers.

Am I right in assuming that if I give the rest of the drive train a really good clean and lube (which was the plan all along anyway), that this might solve the breaker-tripping issue?

Other than your help, assistance and advice, my next test will be in a couple of weeks when I have cleaned/lubed and reassembled the headstock (following the amazing advice on this forum).

AtDhVaAnNkCsE

Derek Darling

Time will tell! To answer your question, 'maybe', hopefully so. How difficult is it to turn all the whirligigs by hand? If they do not now turn easily, then that maybe becomes 'probably'.

BTW TIA is easier!

P.S. I just remembered what yer electrical setup is. The run/full speed has a supply voltage problem(120' of extension cord). What size wire is in it??????????

paulmcohen · Post by **paulmcohen** » Sun Mar 28, 2010 2:23 am

derekdarling wrote:I have a (new to me) Mark V, and I'm beginning the refurb process. When I plugged it in and turned it on, it would run up to speed, then blow the breaker (15Amp). I have removed the belt and tried again, and the motor runs under no load and does not blow the breakers.

Am I right in assuming that if I give the rest of the drive train a really good clean and lube (which was the plan all along anyway), that this might solve the breaker-tripping issue?

Derek Darling

Startup current on a Mark V is close to 15 amps when everything is working correctly, an extension cord will add to the load and will a sticky drive train. Many of us use a 20 AMP circuit, I do and have yet to pop a breaker even with a heavy lathe chuck and large chunk of wood.

dusty · Post by **dusty** » Sun Mar 28, 2010 6:45 am

Does this mean we have two users who are at the end of a 120' extension cord? Fiatben is that way right now because he has yet to run permanent power to his shop.

derek; if you are using a long cord - this could be a contributing factor. If you are plugging in direct to an outlet, I would suggest that you finish your refurb before you tackle the alleged power problem. If you can, try it on a different circuit when you do begin trouble shooting.

The fact that the motor runs says to me that you don't have a serious/ costly problem to repair.

wlhayesmfs · Post by **wlhayesmfs** » Sun Mar 28, 2010 9:11 am

I am not sure on how many are using drop cords for sure. But I was having the same problem and went a picked up a drop cord that was ment for and RV and that solved most of my problems quickly. Later as money and time allowed I then installed a dedicated line for just my SS and now I have not tripped a breaker since. Is the way to go but the drop cord solved about 90% of the issues alone.

8iowa · Post by **8iowa** » Sun Mar 28, 2010 9:51 am

AC induction motors draw around five times the full load current upon starting. Circuit breakers are designed to withstand this as long as the motor comes up to speed very quickly. While the Shopsmith is designed to operate on a standard 15 amp 120V circuit, this is marginal.

Consider that the typical garage only has one or two 15 amp circuits, and most often other devices in the house are on these same lines, which leaves less amps for the Shopsmith. If you add other accessories, such as the DC3300 dust collector, or the wife's washing machine or a freezer, you will be tripping breakers frequently. You can even be left in total darkness if the lights are on that circuit (I've been there).

Another sure way to trip a breaker when on a standard 15 amp recepticle is to forget to lower the speed before changing from saw blade to the much higher inertia 12" sanding disk.

Bottom line; if you are tripping breakers there are many other external considerations to explore before worring about the motor. If at all possible, it is a good idea to wire in a dedicated 20 amp circuit for your Shopsmith.

JPG · Post by **JPG** » Sun Mar 28, 2010 3:24 pm

dusty wrote:Does this mean we have two users who are at the end of a 120' extension cord? Fiatben is that way right now because he has yet to run permanent power to his shop.

. . . . .

You GOT me! I did indeed misspeak!!!!:o

JPG · Post by **JPG** » Sun Mar 28, 2010 3:26 pm

wlhayesmfs wrote:I am not sure on how many are using drop cords for sure. But I was having the same problem and went a picked up a drop cord that was ment for and RV and that solved most of my problems quickly. Later as money and time allowed I then installed a dedicated line for just my SS and now I have not tripped a breaker since. Is the way to go but the drop cord solved about 90% of the issues alone.

What size wire, and how long was the 'RV' drop cord?