"Benson" <[email protected]> wrote in message
news:[email protected]...
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
You can; just make sure it is a double pole switch rated for the amperage
involved.
I put one on my DC to avoid having to get back there.
Like all the other replies you got, I like to unplug my TS. You can't be
too careful.
(breakers should not be used as switches unless they are designed for that
application, which is unlikely.)
In this application the breaker will not be switching any current so its
life should not be impacted. Also, breakers of 30 amps and less don't
seem to be impacted when used to interrupt current. Switching larger
breakers when carrying large currents can impact their life in my
experience.
My personal preference when working on tools that need to be turned off
for service is to place the plug on the tool where I can see it before
and while my hand is at risk. Maybe I'm paranoid but unplugging it is
far more certain than remembering to turn a switch or breaker off.
RB
Roy Smith wrote:
> In article <[email protected]>,
> "Frank Ketchum" <[email protected]> wrote:
>
>
>>I guess, if you don't want to just throw the circuit breaker.
>
>
> Most circuit breakers are not designed for high duty-cycle operation.
> Turn a circuit breaker on and off all the time like it was a switch and
> you'll probably wear it out after not too long.
"Benson" <[email protected]> wrote in message
news:[email protected]...
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
I guess, if you don't want to just throw the circuit breaker. You can if
you want to, just make sure that the switch being used disconnects BOTH hot
leads and not just one and that it can handle the current load of the
circuit as well.
Frank
Benson wrote:
> As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
Well, I think it is more a question of how do you know the device has no
juice? Some people prefer the unplug method because you can visually
check...
There was a recent question here on having a lighted switch that had two
lights, one for when the switch was on and another of a different color
for when it was off (that way you don't accidentally fry/butcher yourself
if the light bulb for "on" went out). I have also seen in a book a tip
about tying a short piece of rope/cord between the blade change tool and
the plug from the machine. That way you cannot possibly use the tool
unless you first unplug the machine.
Anyway, it's all about personalities I think. For me the unlpug method
works, but other people might want another way to assure the power's off.
--
gabriel
"Benson" <[email protected]> wrote in message
news:[email protected]...
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
This is not a good idea. Instead have the 220v outlet on the wall, and then
screw another 220v outlet onto the side of your tablesaw. The outlet on
your TS has a 220V plug coming out of it to plug into the wall. Then plug
your TS into the outlet on the side of your TS.
Aloha, Russell
"Al Reid" <[email protected]> wrote in message
news:[email protected]...
> Those are usually "SWD" switching duty circuit breakers. Unless they are
> listed for switching duty, they are not supposed to be used as such.
That very well may have been as there were no other switches.
Would a 2 walks over to the switch be less trouble than bending over and
unplugging the tool?
"Benson" <[email protected]> wrote in message
news:[email protected]...
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
"Benson" writes:
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
NO, not in my shop.
A plug and receptacle provides a visual disconnect means which a wall switch
does not unless you equip it with a padlock fitting and padlock.
HTH
--
Lew
S/A: Challenge, The Bullet Proof Boat, (Under Construction in the Southland)
Visit: <http://home.earthlink.net/~lewhodgett> for Pictures
This is probably a silly response, but when I'm sticking my hand where it
could easily be turned into ground hamburger or sliced ham, I think I'd have
a happier feeling about it seeing a cable unplugged vs. a switch that's up,
or was it down, or...you get the idea :)
Mike
"Benson" <[email protected]> wrote in message
news:[email protected]...
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
In article <[email protected]>, Benson wrote:
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
I have what you want right here on the table next to my computer.
It's a "Square D Pull-Out Disconnect Switch". The one that I have
is 30 amp fusible model FP221R, but you can get them without fuses.
There's a small bar with a pull tab on it inside an electrical box.
Put the bar in one way and there's no electrical contact. Put it in
the other way and you're good to go. Put the bar in your pocket and
nobody can turn it on while you're working... You can also lock the
box.
This is usually used as an outdoor air conditioning disconnect. I plan
to use this one on a jointer with a five horse motor on it ( 240V@27A ).
On Wed, 04 Feb 2004 15:34:40 -0500, Benson <[email protected]> wrote:
>1. As long as I'm having an electrician wire 230V outlets, wouldn't it
>be desireable to have them switched, so I could change blades, etc.,
>without unplugging the equipment?
That's very dangerous... but if you must use a switch, use a good pull-arm knife switch type in a box, not just some
cheap crap wall switch. Crap breaks... you want a positive break in the circuit, not a toggle spring waiting to zap
you!! And wire the lights on another breaker!
I put an outlet over my saw, its cheap and with my poor memory, saves body parts...
The worst feeling you can have is finding current in a machine you were sure was dead!! Oops is not a good word when you
are working...
PS There has been a ton of electrical questions here, for the record - its 120/240 volts... all those 110, 115, 117,
220, 230 references are out of date.
also, 208 refers to 3 phase industrial power, home current is single phase, center tapped 240. (120+120)
Bob
IBEW
Every 220 in my shop is not a 'plug' in the wall. Instead they are all
a short length (14" or so) of flexible 12-3 coming out of the box on
the wall. Makes unplugging easy.
It's near impossible for me to reset my planer knives without
accidentally hitting the on-switch with my knee. It's just in a bad
place so when I set the knife on top, kneel down to test it with the
dial gauge, then get up off my knees, my left knee always hits the
switch. I've never turned it on but I sure feel better knowing there
is no juice present.
jb
"Roy Smith" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>,
> "Frank Ketchum" <[email protected]> wrote:
>
> > I guess, if you don't want to just throw the circuit breaker.
>
> Most circuit breakers are not designed for high duty-cycle operation.
> Turn a circuit breaker on and off all the time like it was a switch and
> you'll probably wear it out after not too long.
Actually I worked at a company that used circuit breakers to turn off the
shop lights and the compressors. Never recall a breaker failing in the 10
years that I worked there.
If MY hands were in jeopardy, I'd open the breaker to the 220 leg feeding
the outlets. If you current configuration doesn't allow that I believe I
change it. Hands are a rather critical appendage! Keeping power off the
machines when repairing or adjusting is only common sense to me.
Don Dando
"Biff Steele" <[email protected]> wrote in message
news:[email protected]...
> Every 220 in my shop is not a 'plug' in the wall. Instead they are all
> a short length (14" or so) of flexible 12-3 coming out of the box on
> the wall. Makes unplugging easy.
>
> It's near impossible for me to reset my planer knives without
> accidentally hitting the on-switch with my knee. It's just in a bad
> place so when I set the knife on top, kneel down to test it with the
> dial gauge, then get up off my knees, my left knee always hits the
> switch. I've never turned it on but I sure feel better knowing there
> is no juice present.
>
> jb
Those are usually "SWD" switching duty circuit breakers. Unless they are
listed for switching duty, they are not supposed to be used as such.
"Leon" <[email protected]> wrote in message
news:[email protected]...
>
> "Roy Smith" <[email protected]> wrote in message
> news:[email protected]...
> > In article <[email protected]>,
> > "Frank Ketchum" <[email protected]> wrote:
> >
> > > I guess, if you don't want to just throw the circuit breaker.
> >
> > Most circuit breakers are not designed for high duty-cycle operation.
> > Turn a circuit breaker on and off all the time like it was a switch and
> > you'll probably wear it out after not too long.
>
> Actually I worked at a company that used circuit breakers to turn off the
> shop lights and the compressors. Never recall a breaker failing in the 10
> years that I worked there.
>
>
All of our 220v tools are just wired directly to the circuit with wire
nuts, no plugs/outlets anywhere. Wasnt my decision, doesnt make me
particularly happy. Meant that when the switch on the drum sander melted
a spade lug, I had to go find the stupid breaker just to safely open it >:O
On Wed, 04 Feb 2004 21:08:09 +0000, gabriel wrote:
> Benson wrote:
>
>> As long as I'm having an electrician wire 230V outlets, wouldn't it
>> be desireable to have them switched, so I could change blades, etc.,
>> without unplugging the equipment?
>
> Well, I think it is more a question of how do you know the device has no
> juice? Some people prefer the unplug method because you can visually
> check...
>
> There was a recent question here on having a lighted switch that had two
> lights, one for when the switch was on and another of a different color
> for when it was off (that way you don't accidentally fry/butcher yourself
> if the light bulb for "on" went out). I have also seen in a book a tip
> about tying a short piece of rope/cord between the blade change tool and
> the plug from the machine. That way you cannot possibly use the tool
> unless you first unplug the machine.
>
> Anyway, it's all about personalities I think. For me the unlpug method
> works, but other people might want another way to assure the power's off.
In article <[email protected]>,
"Frank Ketchum" <[email protected]> wrote:
> I guess, if you don't want to just throw the circuit breaker.
Most circuit breakers are not designed for high duty-cycle operation.
Turn a circuit breaker on and off all the time like it was a switch and
you'll probably wear it out after not too long.
In article <[email protected]>, RB <[email protected]> wrote:
> In this application the breaker will not be switching any current so its
> life should not be impacted. Also, breakers of 30 amps and less don't
> seem to be impacted when used to interrupt current. Switching larger
> breakers when carrying large currents can impact their life in my
> experience.
I don't believe it's the current interruption that causes the wear, it's
just the mechanical movement of the internal parts. Circuit breakers
(unlike normal switches) are designed to interrupt currents many (like
100's) times their rated capacity. They're also designed to trip even
if the external handle is mechanically held in the "ON" position. The
design tradeoffs required to meet those requirements usually involve
some kind of spring-loaded mechanism, which leads to a relatively high
mechanical wear each time the machanism is cycled.
If the contactors can handle interrupting a 1000 A overload, the arcing
caused by interrupting a 20 A load isn't going to be significant.
> My personal preference when working on tools that need to be turned off
> for service is to place the plug on the tool where I can see it before
> and while my hand is at risk.
There's no doubt that that's the safest way to do it.
"ATP" <[email protected]> wrote in message> >
> > How is that different or better than just plugging the saw into an
> > extension cord?
>
> Extension cords are not to be used "in place of fixed wiring"- so unless
> it's a portable saw temporarily set up, it's a code violation. Using a
home
> made extension cord to connect the 220V receptacle by the TS to the
> receptacle on the wall would also be a violation.
My Cabinet saw is portable and moved every time I use it.
"Ed Clarke" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>, Benson wrote:
> > 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> > be desireable to have them switched, so I could change blades, etc.,
> > without unplugging the equipment?
>
> I have what you want right here on the table next to my computer.
> It's a "Square D Pull-Out Disconnect Switch". The one that I have
> is 30 amp fusible model FP221R, but you can get them without fuses.
>
> There's a small bar with a pull tab on it inside an electrical box.
> Put the bar in one way and there's no electrical contact. Put it in
> the other way and you're good to go. Put the bar in your pocket and
> nobody can turn it on while you're working... You can also lock the
> box.
>
> This is usually used as an outdoor air conditioning disconnect. I plan
> to use this one on a jointer with a five horse motor on it ( 240V@27A ).
>
That is the correct answer! Combines the comvenience of a switch with the
safety of true current interruption! Switches can fail in such a way that
they pass current unexpectedly, but this unit is fail safe. I would still
remove the bar when changing blades. I think we humans need a strong visual
key (like the plug laying on the floor, or the bar sitting on the work
surface) to reinforce our safety habits over the many hours in the company
of tools that can hurt us. All it takes is one mistake...
Tom M.
Leon wrote:
> "Russell Shigeoka" <[email protected]> wrote in message
>>
>> This is not a good idea. Instead have the 220v outlet on the wall,
>> and then screw another 220v outlet onto the side of your tablesaw.
>> The outlet on your TS has a 220V plug coming out of it to plug into
>> the wall. Then plug your TS into the outlet on the side of your TS.
>>
>> Aloha, Russell
>
>
> How is that different or better than just plugging the saw into an
> extension cord?
Extension cords are not to be used "in place of fixed wiring"- so unless
it's a portable saw temporarily set up, it's a code violation. Using a home
made extension cord to connect the 220V receptacle by the TS to the
receptacle on the wall would also be a violation.
"Russell Shigeoka" <[email protected]> wrote in message
>
> This is not a good idea. Instead have the 220v outlet on the wall, and
then
> screw another 220v outlet onto the side of your tablesaw. The outlet on
> your TS has a 220V plug coming out of it to plug into the wall. Then plug
> your TS into the outlet on the side of your TS.
>
> Aloha, Russell
How is that different or better than just plugging the saw into an extension
cord?
When I change a blade, I _really_ want to see that cable and plug laying on
the top of the tool. Then I know for sure it is safe to work on the blade.
Have your electrician place the new 230 outlet where it is real easy to get
at.
DexAZ
"Benson" <[email protected]> wrote in message
news:[email protected]...
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
Benson <[email protected]> writes:
> 1. As long as I'm having an electrician wire 230V outlets, wouldn't it
> be desireable to have them switched, so I could change blades, etc.,
> without unplugging the equipment?
If you don't trust the switch on the tool, why would you trust the
switch on the wall?