97-10 Running In Reverse

[beans]

I have a buddy who has a 97-10, he said it was running slow.He disconnected the motor ,took off the cover and took out the part to clean. I guess they are some kind of points or brushes,i have not seen the motor myself.Well he put it back together ,said it started strong,runs good ,but it runs in reverse.He said he changed the wire connections,but still runs in reverse ,any ideas would be helpfull before i go visit him.Thank you for your time.

[Ferg]

Normally if it is on 120 volts doesn't matter which wire is to the posts, technically. If you reverse the wires and the hot wire happens to be connected to the case of the motor you will get shocked every time you touch it. If motor is on 220 volts you can reverse the motor by exchanging the two hot wires, leave the ground wire alone.

That said: I would bet he screwed up the parts when he put them back in.

ferg

I have a buddy who has a 97-10, he said it was running slow.He disconnected the motor ,took off the cover and took out the part to clean. I guess they are some kind of points or brushes,i have not seen the motor myself.Well he put it back together ,said it started strong,runs good ,but it runs in reverse.He said he changed the wire connections,but still runs in reverse ,any ideas would be helpfull before i go visit him.Thank you for your time.

[sandyt]

Does it have 2 or 4 brushes? If it has 4 he must have switsched the connectons. I had it with my startermotor once. But does it have 4???

Does it have a capacitor?

Don't know what kind of motor is in it.

Sandy.

[

[beans]

I don't know if it has 2 or 4 ,i think its on 110. I will not be able to see it till tomarrow,thanks for the quick replys.

[sandyt]

It's a industrial machine isn't it? The industrial machines in Holland all (95? of 100) run on 3 phase motors. When only 1 phase is available there is a running capacitor placed, making it run on just 1 phase wich all houses have. 220 Volt though. This way the motor can run both ways.

When it's a one phase motor there is also a capacitor placed, called a starting capacitor. It makes the motor run in one direction. You can choose wich way by connecting it different.

I guess there isn't much difference between 110 volts (US) alternating curent and 220 volts alternating current (europe). Or am I wrong??

That's all where my knowledge gets me so far.

Let us know when you get with your friend.

Sandy.

[sandyt]

I am talking about plain simple clutch motors. Do not have any experience with servo motors yet.

I do have one motor with Efka variostop but that one also can run on 1 or 3 phase due to the capacitor.

Sandy.

[Art]

Hi Sandy,

The only difference is 100 volts and 10 cycles. Alternating current is the same, phase is usually the same. Your 220v motors usually run ok on one leg of a 3 phase circuit (208v) over here. Our 120v single phase motors may not be built (dielectric strength) to run very well on your 220v.

Art

I guess there isn't much difference between 110 volts (US) alternating curent and 220 volts alternating current (europe). Or am I wrong??

Sandy.

[CowboyBob]

I usually try to take the easy way out & if you cross the belt going to the head this will let your reverse rotation motor run the right way,You might have to buy a longer belt or splice it.They grip better when crossed too.

Bob

[Les No6]

Sounds like he’s wired the starter windings the wrong wayaround you have to just swap these, if you are lucky there will be a wiringdiagram inside the cover somewhere. To identify different winding use a circuittester winding terminals give a circuit and separate winding’s give open circuit,just swap the starter winding’s around and leave the running winding’s alone. Ifyou swap both winding you keep the same direction.

[beans]

Well took the cover off the motor ,i dont know anything about motors but it looked like he put it back the same way it came out.There is a plate that has the brushs ,the whole plate slides off the shaft.He cleaned the brushes slid back in and ran in reverse.Well for now we crossed the leather belt and its working,thanks for the idea Sewmun.also thanks for everyone who offered a suggestion this indeed is a great forum.

[amuckart]

If there are two brushes, and you swap the brush casings (and therefore the wiring, and polarity relative to the field coils) then the motor will run backwards.

[Gregg From Keystone Sewing]

I usually try to take the easy way out & if you cross the belt going to the head this will let your reverse rotation motor run the right way,You might have to buy a longer belt or splice it.They grip better when crossed too.

Bob

1st thing I thought of as well. I remember all the 97-10s I've seen running have the belt crossed up like this.

[CowboyBob]

The leather belt will grip better when crossed too!

Bob

[steveh]

I usually try to take the easy way out & if you cross the belt going to the head this will let your reverse rotation motor run the right way,You might have to buy a longer belt or splice it.They grip better when crossed too.

Bob

BoB,

Could you please explain "cross the belt"? Do you mean to to put the belt in a figure eight from the drive pully to the machine pully?

Thank You

Steve

[TwinOaks]

Yes, a half twist in the loop....which makes a figure 8 and changes the direction of rotation.

[sandyt]

Hi Art,

But are you using that running capacitor overthere also? In case of 3 phase motors ofcoarse to run on a 1 phase circuit? Steinmetz circuit? Very few people know about it overhere. Most of them think a 3 phase motor can not run on a one phase cicuit. You will loose a lot of torque, but it's still way enough for sewing.

I know the motor doesn't like it but I have a Hamilton beach scovil milkshake mixer 110 volts running on 220 volts. It makes an awfull noise but it's still okay for a few years now. Still waiting to smell some smoke comming out of it, haha...

Sandy.

Hi Sandy,

The only difference is 100 volts and 10 cycles. Alternating current is the same, phase is usually the same. Your 220v motors usually run ok on one leg of a 3 phase circuit (208v) over here. Our 120v single phase motors may not be built (dielectric strength) to run very well on your 220v.

Art

[CowboyBob]

Steve,

Twinoaks explained it & this is how we always used to setup a 97 years ago since it makes the belt have more contact with the pulley it won't slip as easy.

Bob

[Art]

Hi Sandy,

Remember with the Steinmetz, you implement the capacitance to provide symmetrical voltage at the rotor, but the load must be constant for the value of the capacitor or the voltage will become more and more asymmetrical as the load varies outside design characteristics. The further outside the design the load becomes the more inefficient the motor because of the imbalance in the phases, hence heat goes up too. This is a problem with most motors as they requite significantly more current to start than to run, so you implement two capacitors, one for starting and one for running which is ok if there are only two predictable loads, but that isn't the way it is for the typical motor, so good power distribution is a crapshoot, and the heat generated will cause it's own set of problems.

I generally run three phase motors with a VFD (variable frequency drive) which also gives me the convenience of variable speed, soft start, and good load handling. They are more expensive than the Steinmetz but much more efficient.

Art

Hi Art,

But are you using that running capacitor overthere also? In case of 3 phase motors ofcoarse to run on a 1 phase circuit? Steinmetz circuit? Very few people know about it overhere. Most of them think a 3 phase motor can not run on a one phase cicuit. You will loose a lot of torque, but it's still way enough for sewing.

I know the motor doesn't like it but I have a Hamilton beach scovil milkshake mixer 110 volts running on 220 volts. It makes an awfull noise but it's still okay for a few years now. Still waiting to smell some smoke comming out of it, haha...

Sandy.

[Gregg From Keystone Sewing]

Hi Sandy,

Remember with the Steinmetz, you implement the capacitance to provide symmetrical voltage at the rotor, but the load must be constant for the value of the capacitor or the voltage will become more and more asymmetrical as the load varies outside design characteristics. The further outside the design the load becomes the more inefficient the motor because of the imbalance in the phases, hence heat goes up too. This is a problem with most motors as they requite significantly more current to start than to run, so you implement two capacitors, one for starting and one for running which is ok if there are only two predictable loads, but that isn't the way it is for the typical motor, so good power distribution is a crapshoot, and the heat generated will cause it's own set of problems.

I generally run three phase motors with a VFD (variable frequency drive) which also gives me the convenience of variable speed, soft start, and good load handling. They are more expensive than the Steinmetz but much more efficient.

Art

In other words, make a figure eight out of the belt!@#

On a serious note, good stuff Art, and on point. I know just enough about motors to be able to service them and do what I need to within reason, but it sounds like you know beyond that. Good deal.

[sandyt]

You are so right on that theoratical stuff. Not sure if I understand everything though. Not that technical with electronics.

But in Holland (I guess in Europe) it is very very common to use Steinmetz with clutchmotors. Even sewingmachines comming out of the factory have this. Only a working capacitor. No starter capacitor. Could it be because of the difference 110 volts 60 Hz vs 220 volts 50 Hz??

I even use it with hydraulic pums. Works perfectly without getting anything hot or even warm.

It doesn't work with machines witch need a lot of torque al the time like meat mincers.

If Steinmetz doesn't work, I use a VFD also.

Sandy.

[Art]

Hi Sandy,

If you match the power required to the capacitor then for small stuff it should be ok especially with relatively small start loads (clutch motor is good example). If you are to err, then size the cap for the higher load because mismatches in the high load side will generate a boatload of heat. If you are matched for high load then the low loads will do little more than waste a little electricity. The capacitor method is cheap enough and simple enough that you can try it and if you encounter resistance (pun intended) go to the VFD.

Art

You are so right on that theoratical stuff. Not sure if I understand everything though. Not that technical with electronics.

But in Holland (I guess in Europe) it is very very common to use Steinmetz with clutchmotors. Even sewingmachines comming out of the factory have this. Only a working capacitor. No starter capacitor. Could it be because of the difference 110 volts 60 Hz vs 220 volts 50 Hz??

I even use it with hydraulic pums. Works perfectly without getting anything hot or even warm.

It doesn't work with machines witch need a lot of torque al the time like meat mincers.

If Steinmetz doesn't work, I use a VFD also.

Sandy.