I'm sllllloooowwwwlllllyyyyyyy getting around (had
some health problems and a flood in the shop) and
installing my Oneida dust collector. I have a question
for ye all about impellers. (I'm basically making sure I have the motor
wired correctly). Short version: does the impeller --
which has curved blades -- rotate away from the curve of the
blades, or toward it?
Longer version: with the blower housing upside down (so I can
see the impeller), the blades curve counter-clockwise away from the
center hub:
)
o
(
(there's more blades, but the top and bottom are shown above.)
The impeller rotates clockwise, the way the motor is wired up.
This seems counter-intuitive, in that I would have thought the
blades would curve in the same direction as the motor rotates, and
scoop up air.
Any advice appreciated --
Andy Barss
If the dust collector is three phase than rotation must be checke at
start-up, and there are markings on the motor or the equipment it self
to indacate the correct rotation, single phase ( either 115 or 230 volts
) is normaly correct rotation due to the fact that most motors have only
one rotation, those that can be reversed are normaly in the correct
rotation from the equipment maker.
Cheers,
Thomas Cleveland
"Andrew Barss" <[email protected]> wrote in message
news:[email protected]...
> >
> )
> o
> (
>
>>
> The impeller rotates clockwise, the way the motor is wired up.
>
> This seems counter-intuitive, in that I would have thought the
> blades would curve in the same direction as the motor rotates, and
> scoop up air.
>
>
>
> Any advice appreciated --
>
>
> Andy Barss
>
Rotates clockwise as shown.
Greg
"Leon" <[email protected]> wrote in message
news:[email protected]...
>
> >
> If it sucks it is wired correctly, if it blows it is not wired correctly.
>
Really? Ever tried it?
A dust collector fan will blow air the correct direction regardless of motor
rotation. It will move a ton more air spinning the right way, and move just
a comparatively small amount of air turning the wrong way.
Greg
The impellers usually used in dust collection units look like they
rotate "backwards" - for noise reduction reasons.
For lots of info, see...
http://billpentz.com/woodworking/cyclone/Equipment.cfm#Impellers
--
JeffB
remove no.spam. to email
Andrew Barss wrote:
> I'm sllllloooowwwwlllllyyyyyyy getting around (had
> some health problems and a flood in the shop) and
> installing my Oneida dust collector. I have a question
> for ye all about impellers. (I'm basically making sure I have the motor
> wired correctly). Short version: does the impeller --
> which has curved blades -- rotate away from the curve of the
> blades, or toward it?
>
> Longer version: with the blower housing upside down (so I can
> see the impeller), the blades curve counter-clockwise away from the
> center hub:
>
>
> )
> o
> (
>
> (there's more blades, but the top and bottom are shown above.)
>
>
> The impeller rotates clockwise, the way the motor is wired up.
>
> This seems counter-intuitive, in that I would have thought the
> blades would curve in the same direction as the motor rotates, and
> scoop up air.
>
>
>
> Any advice appreciated --
>
>
> Andy Barss
>
"Andrew Barss" <[email protected]> wrote in message
news:[email protected]...
>
>
>
> I'm sllllloooowwwwlllllyyyyyyy getting around (had
> some health problems and a flood in the shop) and
> installing my Oneida dust collector. I have a question
> for ye all about impellers. (I'm basically making sure I have the motor
> wired correctly). Short version: does the impeller --
> which has curved blades -- rotate away from the curve of the
> blades, or toward it?
>
> Longer version: with the blower housing upside down (so I can
> see the impeller), the blades curve counter-clockwise away from the
> center hub:
>
>
> )
> o
> (
>
> (there's more blades, but the top and bottom are shown above.)
>
>
> The impeller rotates clockwise, the way the motor is wired up.
>
> This seems counter-intuitive, in that I would have thought the
> blades would curve in the same direction as the motor rotates, and
> scoop up air.
If it sucks it is wired correctly, if it blows it is not wired correctly.
Typically it is correctly wired if it sucks into the center and blows from
the perimeter.
"Greg O" <[email protected]> wrote in message
news:[email protected]...
> "Leon" <[email protected]> wrote in message
> news:[email protected]...
>>
>> >
>> If it sucks it is wired correctly, if it blows it is not wired correctly.
>>
>
>
> Really? Ever tried it?
> A dust collector fan will blow air the correct direction regardless of
> motor rotation. It will move a ton more air spinning the right way, and
> move just a comparatively small amount of air turning the wrong way.
> Greg
IC
In article <[email protected]>,
Leon <[email protected]> wrote:
>
>If it sucks it is wired correctly, if it blows it is not wired correctly.
>Typically it is correctly wired if it sucks into the center and blows from
>the perimeter.
>
The centrifugal blowers used on dust collectors will not "blow" from
the inlet (center of the fan enclosure) no matter which way the motor
is turning. The low pressure area will always be created at the center
of the impeller and high pressure at the circumference. If the impeller is
directional, incorrect rotation will cause a decrease in efficiency, but
it will never reverse direction of flow.
--
There are no stupid questions, but there are lots of stupid answers.
Larry Wasserman - Baltimore Maryland - lwasserm(a)sdf. lonestar. org
On Tue, 18 Dec 2007 23:04:00 -0600, "Leon"
<[email protected]> wrote:
>If it sucks it is wired correctly, if it blows it is not wired correctly.
>Typically it is correctly wired if it sucks into the center and blows from
>the perimeter.
Air will be accelerated radially outward regardless of the direction
of rotation decreasing the static pressure at the center causing more
air to flow axially into the impeller. Therefore, the impeller will
"blow" rotating in either direction.
If the OP has a blower housing for the impeller, the easiest way to
determine the proper rotation direction is to look at the housing
outlet. Spin the impeller such that the vane tips move in the same
direction the outlet is pointing. IOW, in the picture, if the outlet
is at the top pointing right, the impeller should spin clockwise.
Backward inclined vanes are a little more efficient in that they move
more air (CFM) for a given power input and produce less noise. Forward
inclined vanes move less air for a given power input but can develop a
higher maximum pressure rise across the blower and make more noise
doing it. Note, the information in this paragraph is from (hopefully
ungarbled) memories from over 40 years ago and for which I no longer
have substantiating numbers or reference citations.
Tom Veatch
Wichita, KS
USA
Larry W said:
>The centrifugal blowers used on dust collectors will not "blow" from
>the inlet (center of the fan enclosure) no matter which way the motor
>is turning. The low pressure area will always be created at the center
>of the impeller and high pressure at the circumference. If the impeller is
>directional, incorrect rotation will cause a decrease in efficiency, but
>it will never reverse direction of flow.
Hence the moniker, centrifugal impeller.
Greg G.
"Larry W" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>,
> Leon <[email protected]> wrote:
>>
>>If it sucks it is wired correctly, if it blows it is not wired correctly.
>>Typically it is correctly wired if it sucks into the center and blows from
>>the perimeter.
>>
>
>
> The centrifugal blowers used on dust collectors will not "blow" from
> the inlet (center of the fan enclosure) no matter which way the motor
> is turning. The low pressure area will always be created at the center
> of the impeller and high pressure at the circumference. If the impeller is
> directional, incorrect rotation will cause a decrease in efficiency, but
> it will never reverse direction of flow.
OH!