Date: Fri, 16 May 2014 14:24:35 -0600
Reply-To: Gnarlodious <gnarlodious@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Gnarlodious <gnarlodious@GMAIL.COM>
Subject: Re: Off topic Friday question on switches...
In-Reply-To: <BLU177-W87A78D68358935F7C1B0CE0310@phx.gbl>
Content-Type: text/plain; charset=ISO-8859-1
I was speaking of North American power, which is 120 volts per phase.
Europeans can do whatever they want.
I once saw a man vacuuming his car electrocuted to death after washing his
car, so I am not a big proponent of the European voltages.
Neither do I prefer the Metric System, though I can use it in a pinch.
-- Gnarlie
On Fri, May 16, 2014 at 1:42 PM, James <jk_eaton@hotmail.com> wrote:
> Unless his '220 volt, single phase' induction motor is European - German,
> say - where 220/240V is single phase and the two/three phase power is 480V!
>
> I occasionally see 'misplaced' European motors here in Canada. They can
> be wired to work correctly, but often they are not.
>
> The rest of your description of the wiring and start-up of induction
> motors is quite useful.
>
> James
> Ottawa, ON
>
> > Date: Fri, 16 May 2014 10:03:37 -0600
> > From: gnarlodious@GMAIL.COM
> > Subject: Re: Off topic Friday question on switches...
> > To: vanagon@GERRY.VANAGON.COM
> >
> > I realize this is somewhat abstract terminology. There is no such thing
> as 220
> > single phase. 220 is 2-phase, always. 110 is nominally single phase, and
> > 220 is 2-phase.
> >
> > 120 is single phase, "120/230 single phase" is a nonsensical statement.
> >
> > From the sound of your questions you may have wrongly wired a 2-phase
> > relay. Each phase must be switched through separate contacts to properly
> > suppress arcing when making contact.
> >
> > I'm not an expert, and I don't know what broke in your switch, but I
> > suspect your motor is the type that starts up on a low voltage and when
> > spinning switches over to high voltage. This is normally called a
> wye-delta
> > hookup. If you have wired it wrongly to start up on high voltage it can
> be
> > bad for your neighborhood, your workshop, your switch and your motor.
> >
> > In this scenario, the switch has a timer that spins up your motor, waits
> a
> > short amount of time, then switches to a higher voltage by adjusting
> which
> > phase hits the motor. A 3-phase motor would have 6 terminals running to
> the
> > switch, that is why the switch is so expensive. This wiring setup is used
> > on loaded (clutchless) machinery where the motor must slowly spin up some
> > mass using a lower voltage. Since an induction motor pulls infinite
> current
> > when not spinning, the wye-delta switch limits startup current until the
> > motor and load are spinning fast enough to protect your wiring and the
> > power company.
> >
> > If you are chronically running induction motors wrongly wired you may
> > receive a friendly visit from the power company inquiring as to why your
> > workshop is degrading their "Power Factor". In order for the wires to
> > deliver quality power all three phases must be aligned properly to carry
> > equal voltage and current throughout their phase. Any disruption of this
> > relationship degrades the Power Factor.
> >
> > In the third world people commonly take out the wye-delta switch and
> > substitute a plain switch, resulting in poor quality electricity and many
> > problems throughout the system.
> >
> > -- Gnarlie
> >
> >
> >
> > On Fri, May 16, 2014 at 8:59 AM, Don Hanson <dhanson928@gmail.com>
> wrote:
> >
> > > I have an induction-motored thickness planer, running on 220 single
> phase
> > > power...It came with a magnetic switch that has broken now 3 times and
> > > costs over $50 to replace...Hate that. I found a normal power tool
> switch
> > > in my box, rated for a bigger motor than this tool I am working on
> > > now...but it is a "normal" heavy duty push button power tool switch,
> made
> > > for 120/230 single phase or 208/230/480 three phase... This switch has
> > > four terminals on the back, two labeled "Load" and two labeled
> "Line"...
> > >
> > > So the questions:
> > >
> > > Can I try to wire up this less expensive (and already owned) switch to
> > > make the 220 induction motor work? Right now I am using this tool,
> when I
> > > have to, with my power panel breaker box as the only switch....very
> > > un-safe and not at all convenient. I do need the use of this tool, but
> > > $50 a switch is now (in this tradesmen-unfriendly economic climate) not
> > > very feasible.
> > >
> > > Second question: If I decide to try this hack-job, wiring for the wrong
> > > switch, how should I connect the wires? Do I take the black and white
> > > wires to the two terminals labeled "LIne" and continue on after the
> switch
> > > with the same colors out to the tool from the "Load" posts of the
> switch?
> > > Or do I just break one of the "Line" wires and use just one of the
> 'Line
> > > and Load" terminals, like on a house wiring switch?
> > >
> > > I know this is sketchy stuff but it's really tough for a working man in
> > > the building trades now a days so I can't afford to do it right always
> when
> > > it comes to my own tools and expenses..I tried Goggling "induction
> motor
> > > wiring" etc etc...but I can't understand the wiring diagrams I get
> back...
> > >
> > > Respond off the list if you think you may be able to advise, and thanks
> > > Don Hanson
> > >
>
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