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Grinder wiring, is this correct?

The Cobbler

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was going to replace the cord on my vintage bench grinder . not sure that it is correctly wired?
the hot goes to the switch, . the neutral ( white taped) lead ties to the capacitor
both hot & neutral come out of the motor with a red & brown tied together .
my mind tells me the cap should be the switched side?
thanks for replying
 

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Zeke

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If it ran, wire it the same as you found it. Understanding the function of a capacitor in a single phase induction motor is difficult. But there is a 2nd winding in there that uses the capacitor the way you found it wired. Helps to turn the motor in the correct direction and get it going.

That's all I understand myself. But I rely on don't fix (change) it if it ain't broke.
 

Zeke

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That was my answer, why do you think it's wrong? Are you thinking of a capacitor as a resistor? This might not be very technically correct, but think of the capacitor as a phase shift of the current before it competes the circuit to neutral/ground. It's just doing what needs to be done using a 2nd winding. It may very well disconnect via a centrifugal switch.
 
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TractorJeff

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The capacitor would theoretically drain down on the Neutral/White wire side. This is probably good?

Its early in the morning, first cup of coffee. So maybe a useless point?
Either way I would wire it the same as I took it apart. Someone smarter than me wired it according to an Engineering Drawing originally.
 

torqueman2002

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I'm with TJeff ^, capacitor on the neutral/white wire side, not on the hot/black side. This is from my experience of numerous 'rebuilds' of mostly Craftsman grinders.

I am also on my first cup of java, but have searched many diagrams of grinders with start capacitors, most use a relay instead of a centrifugal switch to control the start-up motor windings.

Given the information/pictures above, my recommendations may need to be adjusted when/if better pictures of the label and wiring are available.

I would replace the power cord and wire it as it came apart and add a chassis ground.
I would replace the light switch with a motor rated power switch.

Note: I typically replace the following when the grinder is being 'rebuilt'.
Bearings
Wire wheels/grinding stones

In the spirit of best practice/safety, replace any missing parts, such as:
spark arrestors
tool rests
eye shields
wheel guards
wheel covers

Here is a diagram of a CM grinder with a start-up capacitor and centrifugal start-up switch. Wire colors may differ from your model.
grinder_cm_1157575_01_elec2.jpg

Also, here is a a thread I posted on OWWM website about a CM grinder.
http://vintagemachinery.org/photoindex/detail.aspx?id=12609

Note: The centrifugal switch is fragile and may be damaged when the end bell is removed.
 

nadogail

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I am a firm believer in “if it isn’t broken, don’t fix it”.

I don’t pretend to understand everything I think I know. There is no point in arguing with success.
 
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