According to William Wixon :
"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.
The reason that it is not approved is that it can create unsafe
conditions, of course.
[ ... ]
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.
Not necessarily -- but it takes some somewhat tricky wiring. I
came up with a fairly ugly pattern when I first re-wired my Clausing
from 120V to 240V. I later re-wired it for a much cleaner design,
after battling the available switch sections in the drum switch. (It
would have been easier with one more switch section, but it would then
need more wires between switch and motor, so this is better overall.
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.
Good to plan for safety. But I know how the eagerness to get
something working can result in an unsafe design.
[ ... ]
i try to be safe. would rather be safe than sorry.
Good.
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.
I wasn't sure whether you had actually run a ground wire and
just not drawn it, so I felt that it was a good idea to mention it just
in case.
[ ... ]
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.
With a 3/4 HP motor, it will probably be a wash in most things,
though the higher currents to be made and interrupted by the drum switch
will result in slightly faster wear of the contacts. I don't know
whether it will make enough difference to result in failure in your
lifetime when used purely as a hobby lathe.
[ ... ]
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.
So you did -- and your drawing showed something which I forgot
to mention in the wiring, so it is good that you posted it, instead of
just assuming that you could use it as described. (It was the position
of the (Red) wire in the motor.
[ ... ]
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.)
:-(
I've seen electricians who would make similar mistakes. It
helps that I've done electricity and electronics as a hobby since late
grade school, and worked in it since the early 1960s until a few years
before I retired. (I spent some of the last years at work as a unix
networking administrator -- another of my hobbys. :-)
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.
As you did. I would like to see the results of a Paint drawing
of this one done from my text description too -- so I can check for
other things which I forgot to mention, like what I forgot in the 240V
option.
[ ... ]
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.
Asbestos? That is an old switch, isn't it. :-)
More recent ones (e.g. about 1957 -- the date of manufacture of
my Clausing) seem to have the label printed on white vinyl. Of course,
the switch may be a later addition, as I've seen catalog photos of the
lathe with pushbuttons instead of a drum switch. :-)
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.
As is common for this kind of motor from other manufacturers.
They all assume that if you want run-time reversible, you will be using
three-phase motors. Nice if you have three phase power available. Or,
if you use a VFD to get variable speed while you are at it.
And the wiring for a three phase motor with the same drum switch
is much simpler.
[ ... ]
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.
Do you have an ohmmeter? It would not hurt to check whether
there are connections between terminals (2) and (4) and any other
terminals before applying power. Just because my tests on my (much
older) motors show that does not promise that HF did not do something
strange. :-)
Anyway -- with the wiring setup which I have suggested for 240V,
you only need three switched wires -- plus the ground -- which may make
it easier. And you can use the terminals for connections there, so you
won't have bundles of electrical tape insulating splices. :-)
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.
I did not check it out at the time -- and the article has now
expired off my newsreader so I can't check it now. As a result, I don't
know what it may show. (It was pretty late at night when I hit it the
first time, and I already had an image in my head of how to do the
wiring and how the motor was set up.
I'll snip my text description for 120V -- as I believe that you
already have it saved off.
thanks Don, i think it did. whew, i'm afraid i'm developing a large karmic
debt to you.
I just like to share what I know to help others.
Enjoy,
DoN.
P.S. Out of curiosity -- why do you not use capital letters for
the start of sentences and for the pronoun "I" (including forms
like "I'd" "I'll", "I'm" and such)?
It makes reading a little more difficult, and it drives my
spelling checker nuts. :-)
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