jamesp
Cave Dweller
Member since October 2012
Posts: 36,331
|
Post by jamesp on Oct 15, 2015 16:20:23 GMT -5
Glad it's working out.
|
|
petrifried
starting to spend too much on rocks
![*](//storage.proboards.com/forum/images/stars/star_teal.png)
Member since August 2015
Posts: 100
|
Post by petrifried on Oct 15, 2015 16:43:15 GMT -5
Thanks again for all your help! I actually hooked up an old electric motor I found in the shop temporarily and Am tumbling right now @ 27 RPMS. =)
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,331
|
Post by jamesp on Oct 15, 2015 17:26:36 GMT -5
I have a 700 RPM HVAC 1/8 HP fan motor. 110 VAC looking thru the junk pile.
Nice slow motor. Would allow a smaller/cheaper big shaft pulley. Plus quieter.
Slower motors better for tumblers(less reduction required)
|
|
|
Post by oregon on Oct 17, 2015 19:53:37 GMT -5
So, I guess it's all in how well the motor is built, the conversion from HP to Amp involves the power factor and efficiency I think? Any idea how to figure the minimal hp to run for 4 - 12lb barrels, or just two? I've been looking through my motor stash, since the tumbler runs 24/7 the blip on the electric bill is noticable. Also worrying that my 5A 1/4 hp motor was actually drawing 7A... So I should replace the motor on the old scott-murray single barrel as well. Here's the motor that got me wondering (it's 230V instead of 115) but this one would still only be drawing the equivalent of 1.3A at 115V.. I haven't seen any 115V 1/8 hp motors with an Amp rating that low. Any of you motor techies want to comment? otherwise I was thinking of the second motor... ![](http://i1074.photobucket.com/albums/w418/korimako/Rocks/motor1.jpg) ![](http://i1074.photobucket.com/albums/w418/korimako/Rocks/motor2.jpg) ![](http://s1074.photobucket.com/user/korimako/media/Rocks/motor1.jpg)
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,331
|
Post by jamesp on Oct 17, 2015 20:11:33 GMT -5
220 volt motors pull roughly 1/2 the amps of a 110 volt motor for a given horsepower.
"I don't think you'll find any difference in efficiency between 110 and 220. You're consuming the same power. The biggest difference is that with 220 you're using 1/2 the current (still the same power) and can use a lighter gage wire. If your whole house used 220 instead of 110, your fuses could be 1/2 their current value. 10 amps instead of 20, etc. But again, power consumption is still the same."
voltage X current = power
110 X 2 amps = 220 X 1 amp= same power for a given 110/220 motor
|
|
|
Post by oregon on Oct 18, 2015 15:46:42 GMT -5
I understand the power consumption of 220 vs 110...
I don't get why different motors have such different current draws for similar HP ratings. I can realize some differences in construction/efficiency, but in the above motor, 1/8 hp at 230 drawing ~.5A, I can't seem to find any 1/8 hp 115V motors drawing much less than 2A, some as much as 7A...
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,331
|
Post by jamesp on Oct 18, 2015 17:11:21 GMT -5
I understand the power consumption of 220 vs 110... I don't get why different motors have such different current draws for similar HP ratings. I can realize some differences in construction/efficiency, but in the above motor, 1/8 hp at 230 drawing ~.5A, I can't seem to find any 1/8 hp 115V motors drawing much less than 2A, some as much as 7A... Analogy(you understand this) Voltage = pressure Current = flow So a one inch water pipe with 100 psi is going to have more flow than a one inch water pipe with 50 psi. A smaller pipe at 100 psi can have the same flow as a 1 inch water pipe at 50 psi. So smaller wire sizes for 220 AC for same HP. Amp ratings are variable. full load amps-start up amps-no load amps-locked rotor amps 7 amps would be a heavily loaded 1/8. AC motors draw the least amps when unloaded at their designated rpm. But a 1 HP will draw more amps than a 1/8 HP no loads or with equal loads up to a point. When the 1/8 starts to get overloaded heat will build up and draw much current, where the 1 hp at the equal heavier load will not get hot and not draw as much. Your low amp 220VAC motor probably should be loaded to draw ~.5 amps for peak operating efficiency. Important when motor runs continuously. Like a V8, it has a cam that determines peak power/peak efficiency etc. Each V8 different. It takes a graph to describe all the amp draw situations. torque related to amps ![](http://ecmweb.com/mag/405ecm08fig2.jpg)
|
|
petrifried
starting to spend too much on rocks
![*](//storage.proboards.com/forum/images/stars/star_teal.png)
Member since August 2015
Posts: 100
|
Post by petrifried on Oct 24, 2015 2:16:23 GMT -5
Got my awesome new motor and the tumbler is in course grind@ 39 RPMs (Math really works;) wired for 1/6 HP! I would like to figure out how to wire in a switch to go between speeds sometime soon, I guess I slept through that class in school. I think with some adjustments I have room for another 12lb barrel. I'm pretty sure that my current barrel is 12lb, but how do I know for sure? Ya'll are awesome and I really appreciate your help. Maybe one day I'll actually be able to contribute something instead of just asking questions:/
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,331
|
Post by jamesp on Oct 24, 2015 4:29:49 GMT -5
Photos ?
As far as wiring the motor with a switch for 2 speeds...I can not say.
Most, and i repeat most, 2 speed motors have a blue or red wire in the motor for low speed connection.
Below is a three speed motor example.
In most cases, white wire in wire from receptacle gets wired to white wire on motor(neutral). And the black wire from receptacle gets wired to the black wire on the motor for high speed. For a lower speed, you have to remove the black wire from the the receptacle to the red or blue wire on the motor.
Sounds like the job for a 2 pole switch-disconnect from black pole and connect to red/blue pole.
White - neutral Black - high speed Blue - medium speed (or low speed) Red - low speed (or medium speed) Green - ground Brown - starting capacitor Brown/white - other terminal of the starting capacitor In most cases, white wire in wire from receptacle gets wired to white wire on motor(neutral). And the black wire from receptacle gets wired to the black wire on the motor for high speed. For a lower speed, you have to remove the black wire from the receptacle to the red or blue wire on the motor.
Sounds like the job for a 2 pole switch-disconnect from black pole and connect to red/blue pole.
|
|
petrifried
starting to spend too much on rocks
![*](//storage.proboards.com/forum/images/stars/star_teal.png)
Member since August 2015
Posts: 100
|
Post by petrifried on Oct 24, 2015 13:07:37 GMT -5
I had it wired for the low setting at fiirst but it seemed like I was tumbling to slow @.26 rpms for my course grind. Last night I disconnected the black from the low speed and hooked up to high speed because I couldn't help but see how the high speed worked. it was a real pain, I felt like I was playing the old school operation game;). But my rpms went up to 39 and seemed like there was more action in my hexagonal barrel ( hopefully a good thing. Maybe a good solution would be to leave it on one speed and just switch out motor pulleys to change speeds? If I get a second barrel leave it on high or if I stick with 1 barrel while I'm learning hook it back to low. The motor ran much quieter on the low speed and puts out a high pitch hiss on high speed + uses more juice.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,331
|
Post by jamesp on Oct 26, 2015 4:03:43 GMT -5
Low speed motors quiet.
Would be nice to change speeds w/a flip of a switch.
|
|
petrifried
starting to spend too much on rocks
![*](//storage.proboards.com/forum/images/stars/star_teal.png)
Member since August 2015
Posts: 100
|
Post by petrifried on Oct 27, 2015 0:06:26 GMT -5
|
|