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Mech to Elec & Vice Versa

07/10/2013 3:28 PM

how/why does the current increase in a motor when mechanical load is increased. say a slip ring motor in Al sheet press.

also

how/why does the speed decrease when when a large current is drawn from the generator?( no speed governor, constant fuel intake/ Valve)

please consider me as an illiterate infant wile answering.

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#1

Re: mech to elec & vice versa

07/10/2013 3:43 PM

we dont do homework questions here

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#2

Re: mech to elec & vice versa

07/10/2013 3:48 PM

1. Because it is a constant speed motor and it is doing more work.

2. Motor speed or generator speed affected?

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#3

Re: mech to elec & vice versa

07/10/2013 3:49 PM

Load.

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#4

Re: Mech to Elec & Vice Versa

07/10/2013 5:43 PM

Because the well-known principle 'Conservation of Energy' says so.

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#5

Re: Mech to Elec & Vice Versa

07/10/2013 11:33 PM

1. To take more mechanical force out of a motor you must put more electrical power into it. What goes out must come from some where!

2. If you only have a limited supply of current you can't get more out so something has got to do without.

Consider getting yourself a basic electricity book, do a Wikipedia search or a Google search. You appear to have less knowledge than you need for this project, that can be fatal! Don't start off on the wrong foot, you may lose it if the project fails!

Good Luck, Old Salt

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#6

Re: Mech to Elec & Vice Versa

07/11/2013 2:54 AM

The OP specified being considered 'as an illiterate infant' while answering.

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It seems that by definition, an illiterate infant will not understand the abstracts and syntactical nature of the words left in other comments (or this one up to this point). Though it is interesting that the OP did not restrict their own communication to that which an illiterate infant might understand or wield.

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The following explanations aren't concise or complete, but might offer something to an illiterate infant beyond our indecipherable text...

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.

.

.

,

,

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#8
In reply to #6

Re: Mech to Elec & Vice Versa

07/11/2013 11:04 AM

Much thanks to "Truth is not . . . " The 3rd illustration is functional. The 1st two great for their graphics. Just one question. How did you get these onto the Forum pages? Also, did you put these together yourself? If so then you are in the league of the ChrisG's of this world.

As for the Motor Question, can be interesdting for people who are brand new to the field but agreed, it might not be as interesting for seasoned technical people in the field as it is a rudimentary issue to them.

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#9
In reply to #8

Re: Mech to Elec & Vice Versa

07/13/2013 12:38 AM

No, none of that artwork is mine.

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I think you might be able to see the URL locations of the images by right-clicking and selecting to view info about the image.

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The animations are in the format of animated GIFs. Just google animated GIF and select images.... Anyway, they can be attached just as any other picture into a comment.

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By the way, I wasn't saying the topic was uninteresting or too rudimentary, I was reacting to the OP's request for treatment as an 'illiterate infant'. I found that kind of funny, as I am never at a loss for words, but I couldn't think of any to type that might have much effect on an 'illiterate infant'.

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#10
In reply to #9

Re: Mech to Elec & Vice Versa

07/16/2013 2:15 PM

"are you offenfed by the " I " word, ......."

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#11
In reply to #10

Re: Mech to Elec & Vice Versa

07/16/2013 3:33 PM

Nope. I'm not offended by any word in particular. Nothing in this discussion offends me. I was merely attempting to respond as the OP requested.

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If the intended recipient were illiterate, that would limit at least the near term possibilities for effectual communication via typed word.

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#13
In reply to #11

Re: Mech to Elec & Vice Versa

07/16/2013 4:07 PM

the illitterate infant cant compute the last your last line. because he is too infant an illiterate.

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#7

Re: Mech to Elec & Vice Versa

07/11/2013 10:57 AM

Dear Mr.polarcamel,

While the Motor is loaded mechanically, the speed FALLS and the BACK-EMF is also falling and hence more current is drawn and viseversa. Refer Text Books.

DHAYANANDHAN.S

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#12
In reply to #7

Re: Mech to Elec & Vice Versa

07/16/2013 4:02 PM

Kind sir could you be more specific please.

I have read the text books which justs stops at the back emf.

but the 250Hp machine seems to draw close to 580A wee bit more and its starting current. Seems impossible?

I thought arrmature reaction had some part in it.

How can the same theory be put 'DC motor'ly

could you suggest a fine text book? please.

7 years back I had no idea i would end up electicaly one day. so i did not study or ask my teachers at Diploma. please help me.

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BJInvention (1); dhayanandhan (1); Fredski (1); lyn (1); old salt (1); polarcamel (3); PWSlack (1); ronclarke (1); truth is not a compromise (3)

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