about constant current source
about constant current source
(OP)
hello, i want to have information on constant current sources, a constant voltage source is practical and reasonable but where do we benefit this kind of a source? what needs constant source?? or there is another explanation ?






RE: about constant current source
Series lighting from a constant current source worked well for airport runway lighting also. There is a vast installed base of industrial instrumentation which uses an adjustable constant current source. To make this more interesting, the device that controls the current is often remote from the device that supplies the voltage.
Bill
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"Why not the best?"
Jimmy Carter
RE: about constant current source
As an electrical engineer, you really should be able to do at least some preliminary research on such a basic question.
Please review basic on-line sources and come back with a more specific question.
RE: about constant current source
RE: about constant current source
The way the question was worded, it sounds as if you do not understand what a constant current source is. If that is the case and you are an engineer as you stated by joining eng-tips, then it is appropriate that you educate yourself on the basics before posting. This is made clear in the posting policies rule #1.
FAQ731-376: Eng-Tips.com Forum Policies: Eng-Tips.com Forum Policies
If English is not your native language and you need help expressing your question, it would be beneficial if you could state this. e.g. "I do not know how to ask, but I am trying to understand how a constant current source is used in power systems."
RE: about constant current source
"Throughout space there is energy. Is this energy static or kinetic! If static our hopes are in vain; if kinetic — and this we know it is, for certain — then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature". – Nikola Tesla
RE: about constant current source
"Throughout space there is energy. Is this energy static or kinetic! If static our hopes are in vain; if kinetic — and this we know it is, for certain — then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature". – Nikola Tesla
RE: about constant current source
bulancak:
One practical application of a D.C. constant current source is the precise determination of ohmic resistances of large generators. Constant current sources can deliver currents with an accuracy of 0.1% or better. You feed a constant current of, lets say, 25 Amps to the collector rings (slip rings) of a field winding and then measure the voltage drop across the collector rings. By utilizing the Ohmic Law you get the most accurate ohmic resistance possible.
In earlier times the situation was less comfortable. You had to use a battery, a series resistance for current adjustment as well as a current meter and a volt meter.
Regards
Wolf
www.hydropower-consult.com
RE: about constant current source
RE: about constant current source
RE: about constant current source
RE: about constant current source
"where do we benefit this kind of a source? what needs constant source?? "
i think it is very difficult for you to understand the aim of asking this question. İ am not asking you the theory of this but practical use in industry. İ think you three have a high esteem of yourself.İ advice you to read the kind explanations of vter and wolf39. Because they were intelligent enough to understand such an easy demand of a man who tries to get information on USE of C.C.S.es...
RE: about constant current source
From my experience, I have seen the airport runway lighting that waross has already mentioned.
For a further explanation (if needed), the series lighting units used in this application are rated in amps, so no matter how many are used (change of circuit impedance), the constant current source adjusts the voltage to keep the current constant. You can see how, for an application such as this, with many lamps spread over a long distance, there would be a significant savings on wiring compared to running the lamps in parallel with a typical (constant voltage) source.
RE: about constant current source
RE: about constant current source
Mike
RE: about constant current source
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If it is broken, fix it. If it isn't broken, I'll soon fix that.
RE: about constant current source
Since voltage sources can deliver ~infinite current, they have downstream circuit breakers.
Compare the V-I curves for both.
RE: about constant current source
I'm not certain, but would electroplating be a constant-current application?
RE: about constant current source
http:
Looks like Google bets even money on that. . .