Author Topic: pm motor  (Read 1228 times)

0 Members and 3 Guests are viewing this topic.

RayW

  • Newbie
  • *
  • Posts: 43
pm motor
« on: February 05, 2006, 01:30:03 AM »
I have a pm motor with the below listed specs and would like to know if it would make a good wind generator.

hp 1.5

rpm 3100

vdc 24

amps 55

                  RayW
« Last Edit: February 05, 2006, 01:30:03 AM by (unknown) »

johnlm

  • Full Member
  • ***
  • Posts: 244
Re: pm motor
« Reply #1 on: February 04, 2006, 07:05:53 PM »
As is my guess is that it would have to be run pretty fast - maybe 1600 to 1800 RPM in order to get 12V out of it.  Once it got up to charging voltage it would be pretty beefy on current.  I suspect it would need to use a fairly large prop with gear up in order to be effective unless you want to live with 3 or 4 volts output.


Explaination:  Some one correct me if Im wrong but in general take the rated voltage of the motor and divide that into the rated rpm to get a rpm/volt expected output.  In this case over 130 RPM for each volt of output.  Approximate.


Johnlm

« Last Edit: February 04, 2006, 07:05:53 PM by johnlm »

georgeodjungle

  • Full Member
  • ***
  • Posts: 193
Re: pm motor
« Reply #2 on: February 05, 2006, 12:19:06 AM »
the easest way,,

 for me at least,

is to place a decimal piont.

like this : you have a pm.


  1. rpm @ 24v & 55 a. so at 10% the rpm will give you.
  2. rpm @ 2.4v @ 5.5a. so,x2 the rpm:
  3. rpm @ 4.8v @ 11 amps


and so on.

you could do the math from there.

thats just a rule of thumb.

it's been close,with in 10% or so.

some one here might have the real math for ya.

or explain it better for you.

it has worked so far,

except for that #$^@&!* $9.95 pm treadmill motor from surplus center.
« Last Edit: February 05, 2006, 12:19:06 AM by georgeodjungle »

RayW

  • Newbie
  • *
  • Posts: 43
Re: pm motor
« Reply #3 on: February 05, 2006, 12:09:48 PM »
I connected this motor to a 12v battery and it turned 1700rpm, so I guess it would need about about 1:8 step up gearing to make any usable power as a wind gennie. Also I thought about re-winding the armature but I think that would be beyond my capabilities. Does anyone have any suggestions for re-winding the armature?

                  RayW
« Last Edit: February 05, 2006, 12:09:48 PM by RayW »

ghurd

  • Super Hero Member Plus
  • *******
  • Posts: 8059
Re: pm motor
« Reply #4 on: February 05, 2006, 10:49:15 PM »
George,

Did you have trouble with the $10 treadmill motor?

G-
« Last Edit: February 05, 2006, 10:49:15 PM by ghurd »
www.ghurd.info<<<-----Information on my Controller

FrankG

  • Full Member
  • ***
  • Posts: 121
Re: pm motor
« Reply #5 on: February 06, 2006, 07:03:18 AM »
Where did you get that motor???


I know a Wind Gen is the last thing I'd be using it for...


From what searching I've done on one+ HP Low Voltage DC Motors that thing is worth a pretty penny...


I'm thinking E-Scooter, E-Cart, Blade Drive for an E-Mower, Test-bed for a Cub-Cadet E-Version, Monster Trolling motor, Battery powered Bush Ready Table Saw, Hydraulic Pump motor for my trucks Dumping box, Tadpole recumbent trike with pedals as foot rests and a last resort... Nope, Wind Mill didn't make my list...


I'm hesitant to suggest that you "Ebay" it, but it's likely that you'd be able to sell it for enough to buy top grade parts and build a killer Dual Rotor system similar to what is the standard on this forum. This would also have the benefit of having greater control over the operating paramaters of it's "Intended" operation as opposed to the typical comprimises that accompany trying to retrofit from a previous application.


And the last but possibly most important consideration is the depth of knowledge that you'd gain via the home built route, and scalability of adding more Mills if required...

« Last Edit: February 06, 2006, 07:03:18 AM by FrankG »

georgeodjungle

  • Full Member
  • ***
  • Posts: 193
Re: pm motor
« Reply #6 on: February 20, 2006, 10:33:06 PM »
yes;

had to spin it to fast to make some juice.

even @ 6:1 on the s rotor.

no where near the other pm motors.

what do you expect for $10....
« Last Edit: February 20, 2006, 10:33:06 PM by georgeodjungle »

oztules

  • Hero Member
  • *****
  • Posts: 1477
  • Country: aq
  • Village idiot
Re: pm motor
« Reply #7 on: February 21, 2006, 04:46:44 AM »
After having just recently completed a rewind of a starter motor armature, the best advise I could proffer is

1. "get some other poor slob to do it"


The second best advise I can give is

2.zubbly, patience patience zubbly, and patience.


Third piece of advise is

3. something I learned by doing a big (grader starter motors are big everywhere) commutator, soldering iron is not remotely good enough if the wires you are using are large, however, a Makite 1200w heat gun, AND soldering iron makes a perfect soldering device for doing the commutator connections, if I hadn't discovered this it would not have worked out at all.


The trick is using the soldring iron to heat up the segment as well as it can, and . aim the  heat gun onto the segment, and the extra heat from the iron on that particular segment allows that one to melt, not the one next to it. My wires were three inhand 1.8mm (x2) Thats 6x1.8mm wires and the copper commutator all at once, soldering iron had no hope on its own. With airgun- easy as hell. this was the key. The rest is just wave winding the armature. Looks complicated but care and patience will do a good job. be methodical.


Being a high speed motor, there is a better chance that the commutator will have the same no of segments as slots, and this will make it easier to follow. If it has twice the no of commutator segments as slots then see 2. above (sorry zubbly, being good is not all it's cracked up to be.)


For the effort, it will in all probability be more for the want of doing it rather than ending up with a super generator. Brushless is better, but for a project, it may interest you if time is not of the essance, and stubbourn patience abounds.


... Most satisfying when it works... although the wife struggles to get enthused, (yes thats nice dear...... continues peeling the potatoes)


..........oztules

« Last Edit: February 21, 2006, 04:46:44 AM by oztules »
Flinders Island Australia

oztules

  • Hero Member
  • *****
  • Posts: 1477
  • Country: aq
  • Village idiot
Re: pm motor
« Reply #8 on: February 21, 2006, 05:04:01 AM »
Frank, that type of motor is prevelant in ADVANCE floor scrubbers.


Last i was over in America, there were rotting hulks from the 70's -90's just waiting for the scrappers. It may be worth your while checking with cleaning supply places for old rust buckets (they were an iron machine in cleaning chemicals and water, rusted like buggery when they changed from epoxy powder coat to painted bodies in the mid 80's.


Kent scrubbers, clarke scrubbers,tennant scrubbers, they all had 1-2hp dc motors, imperial and amatek. We threw out about 70 of them last I was in Melbourne (australia), and if 1 company in Aust has that kind of junk, I can only begin to guess how many are laying around in the USA. The mind boggles.


Saw your site yesterday nice cnc. couldn't find your mild steel hardening page what happened to it?


...........oztules

« Last Edit: February 21, 2006, 05:04:01 AM by oztules »
Flinders Island Australia