"DoN. Nichols" wrote in message

-snip-


1) You are switching the neutral That should not be done in US
practice, as it leaves parts of the motor floating high.

huh. thanks. i'm surprised, well, i don't want to do anything that's not
approved.


2) You have hot and neutral carried through to pins 1 and 4

****. i didn't even notice that teh hot was hot all the way through to the
motor, i was so focused on getting the wires in the right position. that's
part of the reason i decided to bag trying to wire it up to 220 because i'd
have one lead hot all the to the motor there too. just as a fine point and
i don't want to contradict you but i think the neutral is switched, when the
drum switch is in the middle postion it's off. that's what i think anyhow.
dang about the hot though!


Unswitched. This is also not how it should be done. The
unswitched hot is another safety problem, leaving the internals
of the motor hot while it is switched to stop -- and if a widing

yeah, that's part of the reason i figured i didn't want to wire it up to
220, because one lead would be hot all the time. i figured i could just
unplug it, but reading here in the past you guys have said stuff like,
"yeah, but what if you sell it?" or "what if someone else uses it?" so, i
figured i'd better be safe, but i didn't notice the hot was hot all the way
to the motor with this 110 set up too! dang.


grounds to the motor frame inside, it could either render the
motor housing and the lathe hot, thus risking shocking you. Or
-- if you have safety grounds connected (which you have not
shown) it can leave the motor drawing current, and perhaps burn
the (already damaged) windings up -- and possibly start a fire.

i try to be safe. would rather be safe than sorry.



I spent some time posting a text description of how to wire for
240V -- but I don't see it yet, so I can't expect you to have seen it
either.

The first thing that I need to stress here is that you need to
run a safety ground wire from the motor to the case of the switch, to

yeah, was gonna. was so focused on just trying to get the motor to run,
forward adn reverse, was leaving that part out. fully intend(ed) to run a
green ground wire throughout. there's a green screw in the internal wireing
area. thanks.


the frame of the lathe, and on to the safety ground pin in the wall
plug. This wire should be green, and there are probably screws inside
the motor wiring box with their heads painted green, and maybe one in
the drum switch box (though that may be old enough so they didn't paint
the screw head green.)

If you really want to run on 120V (I forget what horsepower
rating this motor is, but a 1-1/2 HP motor run on 120V can sometimes
trip the circuit breaker on starting surges. 240V is by far the better


i preferred wiring it to 220/240, heard motors are more efficient that way,
but the 220 wiring was totally boggling my mind. it's a 3/4 horse motor.


choice for something which you will be starting and stopping frequently

Your wiring shown probably would run -- but it is unsafe.


ok. back to the drawing board.




Check out what I wrote in the other article. I think that
should do it for you.


thanks. hope so. i briefly scanned it, will get back to it in detail after
this.



If you still have questions -- or can't find the article -- send
me an e-mail and I'll dive back into it.

But -- if you *really* want to run at 120V, let me describe how



thanks very much for taking the time to help me with this. i had no idea
where to even start to look for information about this. (figured i was
going to have to talk to an electrician and they always seem to want money.)
:-(



to do it *safely*. I'm going to be assuming that the power is brought
into the drum switch as you have shown in your fwd-rvse.jpg image.

I'm also going to label the switch terminals as follows:

(A) (B)


(C) (D)


(E) (F)

so I can talk about them, and you can sketch them out on paper if you so
desire.


i started to make a Paint drawing of your schematic and realized that i DO
want to (at least TRY) to wire it up to 220. so. i'll have to go read your
other post.


-snipped, for now-




And this should give you reversing operation at 120V. (As
suggested above -- 240V operation would probably be a better choice, and
that would be covered in my other article -- which you may be reading as
I type this one. :-)

Part of the problem here is that the motor's wiring scheme is
tailored to cookbook instructions, and actually hides the information
about what is inside. I wonder whether they have wiring instructions
for each brand of drum switch in addition to what instructions you found,


the drum switch has several different wiring diagrams printed on what
appeaers to be asbestos adhered to the curved sheet metal cover. i wanted
to scan it to show you guys but can't. the harbor freight instructions are
pretty basic, no drum switch instructions.



which were assuming that you either wanted the motor to always run
clockwise or always wanted it to run counter-clockwise -- and had no
need to switch it between those (which is what three-phase motors are
for, after all. :-)

that's what the HF instructions are like. one way or the other.


Let's try to sketch what is actually in that motor -- using "(#)"
to indicate a numbered terminal, and "(C)" to indicate a colored wire.
Note also that I use only numbers 1 though 4, so 'O' is a letter --
orange wire, not a number.

+----------------------------------------+
| |
| (1)+WWWWWWWWW-(W) |
| |
| (2) |
| |
| (3) |
| |
| (4)-WWWWWWWWW+(O) |
| |
| (B)-WWWWWWWWW--)|-o/o-(R) |
| |
+----------------------------------------+

"-)|-" is the capacitor

"-o/o-" is the centrifugal switch.

"-+WWW-" is a motor winding.

The '+' in a motor winding shows the start of the winding, which
is important when connecting them in series or in parallel.
(Part of what is hidden by the design of the motor's terminal
plate.)


i dissassembled the motor... so i could push the wires out of the way,
(when i feed in the four wires from the drum switch the wires that are
already there inside the motor were going to be MAJORLY in the way) and saw
the innards, but i was so focused on moving the wires i didn't really pay
attention to what's wired to what. duh. i didn't even take notice of teh
two non- wired pins that you've mentioned.



Note that terminal (2) and (3) show *nothing* connected to them.
This is exactly how it is. They are there so you don't have to
splice wires together and wrap it all in electrical tape.

So -- when you connect to the (W) and (O) wires, and nothing to
the (1) and (4) terminals, other end of each winding is
connected to nothing, so no current is flowing.


did you check out the link posted by Glenn? they have pretty nice
illustrations there. .pdf file though, takes a long time to download.



If you connect (W) to (4), and (O) to (1), then the two run
windings are connected in parallel, and they both get full 120V
from connections to (1) and (4).

If you connect (W) and (O) together, the two run windings are
connected in series for 240V operation. This is done in the
motor drawings which you posted by connecting both of these to
terminal (3), which is otherwise doing nothing. This still
leaves terminals (1) and (4) for the incoming power.

However -- this center point (3) also has a voltage which is
120V different from either end of the incoming power, so it can
be used to power that 120V start winding. And each of these
windings has only 120V across it, even though you have 240V
connected to the motor.

I hope that this helps.


thanks Don, i think it did. whew, i'm afraid i'm developing a large karmic
debt to you.



Enjoy,
DoN.



b.w.