Author Topic: A good day at work  (Read 13607 times)

Rob.Wilson

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A good day at work
« on: July 27, 2010, 03:19:22 PM »
Hi Lads

This week i have good job ,,to  decommission a few  stock pickers for a major bearing manufacturer  , wile i was hard at work having a brew and a tab ,, the head of maintenance came over and said i need to get over to the mechanical stores as they are having a clear out of old stock ,he thought it best  to let me no now, to save me having to get the stuff  back out  of the skip , spoil sport  ::) 

This is what i came away with  :D
A tub full of bits and bobs ,, welding stuff , TCT tips N stuff


A couple of long air actuators and heavy ball lead screw


Selection of Knobs


A good selection of linear bearings , LY20 ,LA35 ,LGY30,LJ20   all new  :D 





Some end effectors  ,,cos they look cool  :lol:
 

And best of all a tap for the garden ,,, save me a few quid


Wonder what tomorrow will bring  :D,,,,,,,,,, best think of some thing to build  out of this lot  :scratch:


Rob


Offline John Stevenson

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Re: A good day at work
« Reply #1 on: July 27, 2010, 03:22:54 PM »
Linear driven grippers with adjustable ratchet handles for turning the garden tap on, ball screw operated of course.

Just get it all done in time for the hosepipe ban.

John S.
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Offline dsquire

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Re: A good day at work
« Reply #2 on: July 27, 2010, 05:36:21 PM »
Rob

WOW. What else can one say. I think that you have hit the mother load. That is some impressive bit of kit you have saved from going to the landfill. Of course now we will expect lots pf new projects to use the pieces up. Its time for  :proj: to run rampant.  :ddb: :ddb: :ddb: :ddb: :ddb: :ddb: :ddb:

Cheers  :beer:

Don
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Offline SKIPRAT

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Re: A good day at work
« Reply #3 on: July 27, 2010, 05:58:51 PM »
Rob

And i thought i was a pretty good faciltator with a haul like that you definitely take the biscuit  i like the bit about bypassing the skip  saves a lot of skipdiving but takes away it's joys .

Cheers Paul 
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Rob.Wilson

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Re: A good day at work
« Reply #4 on: July 27, 2010, 06:14:49 PM »
Hi Lads

 :lol: :lol: :lol: :lol: :lol: sounds like a plan John

Hi Don ,,,, Oh it will have to be something  good ,,, maybe a cnc  router or profile cutter  :med:  , just hope they fined me some stepper motors tomorrow  :zap:  :lol: :lol:


Hi Paul ,,,,  :lol: :lol: :lol:  Good old health and safety  ::)  i like a good rummage head down feet sticking out of the skip ,fighting for that bit of treasure ,,,,,,,,,,,,, now on the sites i visit, i have a Rob may want that  box/stillage ,,,,no sport at all  :bang: :bang:

Rob







Offline Brass_Machine

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Re: A good day at work
« Reply #5 on: July 27, 2010, 09:51:18 PM »
Very very nice Rob! Those linear bearings are awesome to have. I plan on buying a few myself... lucky bastid!

Eric
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Offline Tinkering_Guy

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Re: A good day at work
« Reply #6 on: July 27, 2010, 09:57:51 PM »
Incredible!  Excellent haul!  I am soooo envious.. haven't yet found a place where I can pick. :(
Tinkering_Guy
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Offline Brass_Machine

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Re: A good day at work
« Reply #7 on: July 27, 2010, 10:32:51 PM »
Incredible!  Excellent haul!  I am soooo envious.. haven't yet found a place where I can pick. :(

Me either. Would kill for a haul like that!
Science is fun.

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Offline PTsideshow

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Re: A good day at work
« Reply #8 on: July 27, 2010, 11:11:22 PM »
Its always nice when a plan comes together, That was really slick having been notified , so the poor guy didn't have to haul it out do all that work of pitching it in the skip!  :lol:
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Offline Stilldrillin

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Re: A good day at work
« Reply #9 on: July 28, 2010, 02:25:36 AM »
Nicely done Rob!  :clap:

Right place. Right time.

So much potential.......  :thumbup:

David D
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Offline andreas

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Re: A good day at work
« Reply #10 on: July 28, 2010, 03:32:09 AM »
Soooo…now what’s next for them to scrap? Let’s say….a couple of stepper motors +drive electronics, and maybe a spindle motor?

Good harvest Rob :thumbup:
Cheers
Andreas


 :proj:

Offline jim

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Re: A good day at work
« Reply #11 on: July 28, 2010, 04:08:18 AM »
good haul!!

our place is having a "tidy up", last year they had a good one, a skip full of measuring stuff (missed out on that one!).

it never ceases to amaze me what companies throw away. one place i worked chucked a box of sample tips, lucky for me i rescued them!!
if i'd thought it through, i'd have never tried it

Offline Brass_Machine

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Re: A good day at work
« Reply #12 on: July 28, 2010, 10:06:40 AM »
....

it never ceases to amaze me what companies throw away. one place i worked chucked a box of sample tips, lucky for me i rescued them!!

I have got to find a job like that!
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Rob.Wilson

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Re: A good day at work
« Reply #13 on: July 28, 2010, 02:59:40 PM »
Cheers lads

The stuff that big company's throw away  ::)  ,, more stuff today  :D

A few motor inverter what's its ,,,,,,,,,,,, will need help with these , no manuals  :scratch:  ,,,,,,,, i think the larger one is 440 volts too .
 

Another ball screw ,, and a high pressure gas manifold ,, just what i have been looking for so i can run two gas bottles on the furnace


Box of bearings and  guide bushes


Tub of may need one day stuff ,, the box with the switches on i have no idea what its for ,but i think the switches are the same ones John S, had on his gear cutting machine he made ,, i think the word encoder was mentioned that day as well ,, so i got a few of those .




looks like i will have to build a CNC mill to make good use of this 30 NT tooling


And thats today's haul

Rob


Offline Brass_Machine

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Re: A good day at work
« Reply #14 on: July 28, 2010, 03:12:34 PM »
WooHoo! Nice haul again!

Rob, they hiring where you work??

Eric
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Rob.Wilson

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Re: A good day at work
« Reply #15 on: July 28, 2010, 03:18:50 PM »
Hi Eric

The pay is crap ,,,,,,always skint,,,,,,,,,,,,,  that why i am always in skips  :lol: :lol: :lol:

Rob

Offline dsquire

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Re: A good day at work
« Reply #16 on: July 28, 2010, 03:28:16 PM »
Rob

I don't know what your going to build but it's going to have to be something CNC with all the goodies that you have following you home. I am starting to get jealous Rob. I'll keep watching to see what happens tomorrow.  :) :D :) :D

Cheers  :beer:

Don

PS: Looks like you got a bit of a bonus this week.  :lol: :lol:

« Last Edit: July 28, 2010, 03:30:31 PM by dsquire »
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Offline AdeV

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Re: A good day at work
« Reply #17 on: July 28, 2010, 03:42:08 PM »
Blimey Rob, jammy git or what? :bugeye: :bugeye: The only things that end up in the skip where I work are things I put there...  :(

Those motor inverters look to be brand new, I reckon you could raise a few nicker flogging them on eBay. I think they're DC-to-AC converters, if you can post up the model numbers (probably on a label on the back) that'd help.

That load indicator(?) looks like it will give you a nice haul of bits, 7-segment displays for example.

If you ever run short of space to keep your skip finds, just give me the nod, I'll be over with a big van before you can say "where are you taking it, then?"  :lol:
Cheers!
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Offline andreas

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Re: A good day at work
« Reply #18 on: July 29, 2010, 02:51:55 AM »
No way!!!....this is not happening!!!!!....dear Rob, if you want to get rid of something.... :)

All the best
Andreas

Rob.Wilson

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Re: A good week at work
« Reply #19 on: July 29, 2010, 11:30:02 AM »
Cheers lads

Getting better ,,, the electrical department got wind  of my little project and donated a box of stuff  :D

The box


Three 5 phase stepper drivers ,, two 5 phase motors and a DC motor / controller kit




And a power supply


Sorry if this seams like a bit of a gloat ,,,,,,,,,, :med:

Cheers Rob




Offline dsquire

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Re: A good day at work
« Reply #20 on: July 29, 2010, 11:46:55 AM »
Rob

 :jaw: :bugeye: :jaw: :bugeye: :jaw: :bugeye: :jaw: :bugeye: :jaw:
I hate to have to say this but I think that we are all starting to hate you.  :lol: :lol: :lol:

I am going to have to go back and reread this thread several times to see if it says what I think it says.  :bang: :bang: :bang: :bang: :bang:

Cheers  :beer: :beer: :beer: :beer:

Don
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Offline Brass_Machine

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Re: A good day at work
« Reply #21 on: July 29, 2010, 11:53:16 AM »
Nah this is a good gloat. Pretty sure we are all happy for you!  :headbang: Just make sure you do something very cool with it! ah hell, why am I telling you that...

Now, lets hop on a boat and head to Robs' house!

Eric
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Offline jim

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Re: A good day at work
« Reply #22 on: July 29, 2010, 11:54:03 AM »
it just gets better!!

i had no such luck, went back to work after a few days off, the skips had been emptied :doh: :doh:
if i'd thought it through, i'd have never tried it

Offline Darren

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Re: A good day at work
« Reply #23 on: July 29, 2010, 02:49:20 PM »
Rob, I'm stunned ..... you got no excuses now and no doubt you being you a blooming good project is being hatched, or will be ... have fun  :thumbup:
You will find it a distinct help… if you know and look as if you know what you are doing. (IRS training manual)

Offline PTsideshow

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Re: A good day at work
« Reply #24 on: July 29, 2010, 07:11:03 PM »
 :bugeye: :thumbup:  :clap: :bugeye: :thumbup: :clap:
 :borg:
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Offline Stilldrillin

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Re: A good day at work
« Reply #25 on: July 30, 2010, 03:14:45 AM »
Oh..... My!  :bugeye:

It`s just too much to take in.......

"My cup is full, and runneth over".......

David D
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Still drilling holes... Sometimes, in the right place!

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MrFluffy

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Re: A good day at work
« Reply #26 on: July 30, 2010, 05:14:10 AM »
Drool, Id love to find that. And its great that your employers let you take stuff.
We get disciplined if we took a thing from the skip, even though our employer has to pay a disposal company to get rid of it per unit at the other end, so we'd actually be saving them money! It nearly makes me cry sometimes walking past 5k bits of test kit just sitting out in some stillage in the rain...

Offline John Stevenson

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Re: A good week at work
« Reply #27 on: July 30, 2010, 06:37:41 AM »
Cheers lads




Sorry if this seams like a bit of a gloat ,,,,,,,,,, :med:

Cheers Rob

Not really, those steppers and drivers are Ok if you are building a clock.
At least it's made me feel better   :lol:




« Last Edit: July 30, 2010, 01:23:44 PM by John Stevenson »
John Stevenson

Offline Ned Ludd

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Re: A good day at work
« Reply #28 on: July 30, 2010, 07:44:06 AM »
Hi Rob,
Are you deliberately trying to make us jealous, if so you are succeeding beyond your wildest dreams.
Ned
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Offline John Stevenson

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Re: A good day at work
« Reply #29 on: July 30, 2010, 01:25:06 PM »
Time I thing for another Ju-ju doll, this time a big bastard with a pin the size of a freaking billiard cue..........

John S.
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Offline Bluechip

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Re: A good day at work
« Reply #30 on: July 30, 2010, 01:48:59 PM »
Rob

Looking at one pic. of a 5-phase Stepper ... does it really say 0.57V  1.4A ....

Don't seem much ... ??

Baffled  :scratch:

Dave BC
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Offline John Stevenson

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Re: A good day at work
« Reply #31 on: July 30, 2010, 01:56:26 PM »
Rob

Looking at one pic. of a 5-phase Stepper ... does it really say 0.57V  1.4A ....

Don't seem much ... ??

Baffled  :scratch:

Dave BC


Yer brilliant isn't it ?

Got as much power as a slice of wholemeal toast, 5 phase to boot.
Someone saw Rob coming on this one, makes up for the other gloats  :wave:
John Stevenson

Offline Bernd

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Re: A good day at work
« Reply #32 on: July 30, 2010, 01:56:39 PM »
Well Rob I must say I'm very jealous.  :lol: :lol: :lol: :lol: But good haul.  :ddb:  :ddb:  :ddb:  :ddb: :proj:

Now then, I bet your not going to get a raise in your paycheck for the next..........oh several years.

Bernd

Google Oreintal Motors. The AC version goes for about $2,100.00. That's US dollars. I couldn't find one on the DC series. Could be that's why they were getting rid of them.

« Last Edit: July 30, 2010, 02:13:56 PM by Bernd »
You can't fix "STUPID".

Offline Bluechip

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Re: A good day at work
« Reply #33 on: July 30, 2010, 02:55:37 PM »


Googled Oriental Motors, found a UK site ..

http://www.oriental-motor.co.uk/uk/sites/start.php

Doing a search on the motor Part # in the pic. brings no result ...

There is a reference to PK series motors, but info. doesn't seem to fit ..

??????

Dave BC



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Rob.Wilson

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Re: A good day at work
« Reply #34 on: July 30, 2010, 03:39:21 PM »
 :lol: :lol: :lol: :lol: :lol: :lol: :lol: cheers John  :lol: :lol: :lol: :lol: TWAT

Your eye do not deceive you Dave ,,,,,,,,,,, it dose ,,Looks like its 1.4 amp/ per phase ,,  ,   The   RK SERIES  ,,, is the newer version of what i got ,,, Found the driver/ motor manual on the VEXTA site  for the UPK.W  SERIES   :D



any good  :scratch:

Rob
 Edit :  thats MAX thrust load .,,,,,,,,,,,,,,,,,,,,, U = Unit as these were sold as a set motor and driver kit

Bend ,, they are an AC input unit ,,,,,,,,,,, Have a look on Ebay ,,,, stick   VEXTA in
 

« Last Edit: July 30, 2010, 04:07:27 PM by Rob.Wilson »

Rob.Wilson

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Re: A good day at work
« Reply #35 on: July 30, 2010, 03:56:38 PM »
As John dose not have his voodoo doll up and running ,,,,,,,,,,, this is todays haul  :D




Cheers Rob

Offline doubleboost

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Re: A good day at work
« Reply #36 on: July 30, 2010, 04:55:55 PM »
Hi
Rob
Do you need an apprentice at work for a few days :D :D :D :D :D :D
John

Offline Bluechip

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Re: A good day at work
« Reply #37 on: July 30, 2010, 05:38:52 PM »
Rob

Dunno, you've not put the column headings in, so it doesn't mean a lot   :scratch:

Unless it's a winning line on Bingo you've highlighted ... if it's another gloat JS will do his nut ... :lol:.... again ..  :lol:  :lol:

Never heard of a 5-phase stepper, although there is no reason why they shouldn't exist. I guess you can get better angular resolution, not sure.

After all, some aircraft use 12-phase alternators rather than 3-phase.

You remember I worked on Automated Tape Libraries in those past dark days of being employed ?? Gives me an idea ..

If you get your steppers, linear wotsits, and that storage racking arranged in a suitable fashion ..

You could have the worlds first

AUTOMATED HOB-NOB LIBRARY ..    :thumbup: ... just a thought .. could be a considered very desirable accessory in some places.

But why the 0.57 Volts ???  That seems very strange ..

Can you measure the coil resistance ? Then V should be I x R ?  ie 1.4A x whatever .. or nearly.

Baffled of Belper ..

Dave BC

 











« Last Edit: July 30, 2010, 05:42:04 PM by Bluechip »
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Rob.Wilson

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Re: A good day at work
« Reply #38 on: July 30, 2010, 05:53:22 PM »
Hi Dave

Oh its strange  :scratch: :lol:



Will get the meter oot the morn

Need a 100v ac transformer to power it

Rob

Offline Bluechip

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Re: A good day at work
« Reply #39 on: July 30, 2010, 06:58:31 PM »
Rob

Can't see any info on electrical data, what's with all the 'overhung load' stuff?
You're not developing some unhealthy fetish about large females are you?
Cold showers and lots of exercise cures that, so I've been told.
Although it's taken 60 odd years to work with me ...just have to be patient.

100 Vac seems unusual, what about 110V ac ??

Trannies with 55 - 0 - 55 secondaries are common.

What VA rating ?

Dave BC
« Last Edit: July 30, 2010, 07:08:48 PM by Bluechip »
I have a few modest talents. Knowing what I'm doing isn't one of them.

Offline kwackers

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Re: A good day at work
« Reply #40 on: July 31, 2010, 07:04:09 AM »
But why the 0.57 Volts ???  That seems very strange ..

Can you measure the coil resistance ? Then V should be I x R ?  ie 1.4A x whatever .. or nearly.

Baffled of Belper ..

Dave BC
The low voltage is typical of steppers. You need to get maximum magnetic flux as quick as possible to prevent the torque falling off with motor rpm.
So if you have a 0.57v coil and stick that across it, then say it takes 1/10 of second (remember it's an inductor) for the magnetic field (and current) to build up then you can see you wont be able to spin it very fast since you'll want to move to the next step long before the magnetic field has gained any real strength.

To get round this you stick a very large voltage across - usually somewhere between 20 and 200v. As a result the time for the magnetic field and current to build up is significantly less.

Obviously if you keep the voltage at that level the current will very quickly rise past the rated current and fry the motor, so this is where the stepper controllers come in, they monitor the current and switch the voltage on and off (PWM) to keep the current at the rated value - you can often hear this as a whistling or hissing noise emitting from the motor.

Offline Davo J

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Re: A good day at work
« Reply #41 on: July 31, 2010, 08:11:47 AM »
Hi Rob,
You wouldn't get that much gear in a retirement package, lol

Great score on all the stuff, :beer: and good to see it going to someone thats going to use it.
You must do a good job at work for those blokes to think of gathering it together for you.

Us hobbyist have to pay high prices to get our bit of gear together for the shed, so it's good to see someone get some gear for nothing. :clap:

Dave

Offline Davo J

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Re: A good day at work
« Reply #42 on: July 31, 2010, 08:14:09 AM »
I forgot to add that you need to change the heading to.

Christmas at work, lol

Dave

Offline Bluechip

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Re: A good day at work
« Reply #43 on: July 31, 2010, 08:47:03 AM »
Hi Kwackers

Yup, know about the current limiters etc. Made stepper drivers with the L293 which uses it. Must admit I've never met a stepper motor with a coil voltage as low as 0.57V.

If you work it out the output mechanical HP cannot exceed the DC power input, unless you've invented perpetual motion.

Each phase is apparently 0.57V x 1.4A  ie some 0.8W.

Even with all 5 phases on, (not likely), it only gives 4W  ... or ... 0.0054 HP ?? ..that's if its 100% efficient. Also not likely.

It does have a 100:1 reduction g/box on it .. which will jack up the torque at the expense of revs ..

Still baffled ..

Dave BC



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Offline kwackers

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Re: A good day at work
« Reply #44 on: July 31, 2010, 09:49:12 AM »
What's the steps per turn on the output of the gear box?

Steppers have never been known for tremendous power - the falloff with RPM is too great, but they do have decent torque. Most steppers have some for of mechanical advantage (gearbox, leadscrew etc)

However, (and I'm thinking on the fly here). The DC power isn't going to be correct is it??
For example, if you whack 100v across your motor, then at the point the current increases to 1.4A you're actually dissipating 140w at that instance. So whilst the motor is running I'd think the average power in the motor is much higher.
If I'm correct the DC conditions only really apply whilst it's stationary and in a holding phase.

Offline Bluechip

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Re: A good day at work
« Reply #45 on: July 31, 2010, 10:09:36 AM »
Don't really know ..

All I've done is nail some stepper drivers together and they've worked.   :scratch:

I would think all that happens is the magnetic field in the stepper coil would increase more rapidly than at the nominal voltage.

As soon as the current reached whatever is determined by the sense resistor and the comparator setting it would switch off. Momentarily, until the clock reset the drive, and we start all over again. So, we have some period where there is no drive to the coil. Usual PWM stuff.

Where this leaves the average current I don't know ??

Gonna give up. Just keep thinking in circles ...

Dave BC



I have a few modest talents. Knowing what I'm doing isn't one of them.

Offline kwackers

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Re: A good day at work
« Reply #46 on: July 31, 2010, 10:19:26 AM »
Don't really know ..

All I've done is nail some stepper drivers together and they've worked.   :scratch:

I would think all that happens is the magnetic field in the stepper coil would increase more rapidly than at the nominal voltage.

As soon as the current reached whatever is determined by the sense resistor and the comparator setting it would switch off. Momentarily, until the clock reset the drive, and we start all over again. So, we have some period where there is no drive to the coil. Usual PWM stuff.

Where this leaves the average current I don't know ??

Gonna give up. Just keep thinking in circles ...

Dave BC

Giving this more thought, if you look at the current curve through the inductor for the values we're considering then we're operating on a tiny part of it at the start so we can consider it to be linear.

If we then assume the motor is spinning fast enough so the controller doesn't do any work (thus removing it from the equation) such that each step occurs just as the max current (1.4A) is reached and the voltage we stick across each phase is 100v.

Then it as we switch phases, the current is zero and over the period until the next step builds up to 1.4A at which point we step and do it again. Allowing for the (essentially) linear part of the curve we're operating on and a power supply of 100v then the average current is 0.7A so therefore the power is 70w.

I'm sure there are other factors, but I think we recognise that there's no way a stepper is only generating a couple of watts - plus this describes a mechanism that explains why power increases with increasing drive voltage...

(That blew some cobwebs away.  :smart: )
« Last Edit: July 31, 2010, 01:52:15 PM by kwackers »