That means, to me, that the DC coming off the rectifier is pulsed, because in essence, the rectifier omits the negative part of the sine wave, and therefore the interruption in flow creates current in the coil. Were the current to come directly from the battery there would be no induction...
________________________________ From: "[email protected]" <[email protected]> To: [email protected] Sent: Thursday, May 7, 2009 3:13:36 AM Subject: [Nighthawk Lovers] Re: Electrical I would need more information on what you are doing. Pictures of the ammeter, of this "coil" and the way you connect all this. Just saying that an ammeter is "regular" or not, or that is an "induction" model just makes things confused. If you place a coil around an electrical conductor, you make a current transformer. It's supposed to work for normal steady states measures on AC current only. Now, if you do it around a wire supposed to transport DC current, the only thing you can detect is the rate of increase / decrease of this DC current and, possibly, the maximum value, depending on the exact electrical configuration inside the ammeter (rectifier diodes at ac input, low pass filtering...). Except the new and expensive hall effect sensors ammeters (Fluke 353 or other), usual device like AC current coil probe and normal ammeter gives some results on time variable dc currents. It's not measurememnts, just indications. And changing the probe / the model of ammeter / the caliber will change the results. At 15:24 06/05/2009 -0700, you wrote: >The induction ammeters I have used are a passive coil over a pair of AC >wires; but the coil used to check the draw on the battery of an automobile >does the same thing, and that is direct current and no coils are moving >(rotating) in either example. Explain, please, how this works: the DC is >pulsed because it is rectified alternating. That's the only explanation I >can perceive; and in this case, the induction ammeter referred to would work. > >Stanley554b852.jpg > > > >From: "[email protected]" <[email protected]> >To: [email protected] >Sent: Tuesday, May 5, 2009 8:09:07 AM >Subject: [Nighthawk Lovers] Re: Electrical > >Hello >I'm afraid it's false. Induction ammeter relies on induction forces >beetween a rotating coil and a magnetic field created by magnets to show >the measured value by moving a hand over a graduated scale. I suppose that >by "regular" somebody would say the eletronic stuff sold in most shop, >with digital display. As a matter of fact, in this last brand, no >electromagnetic effec is needed. But what you describe (the coil around >the wire in which you want to measure the current), is just a peripheral >on the input of the ammeter. It is worth only for AC current : You can't >measure DC currents this way. So, on a bike like a nighthawk, no real use >except measure the AC current in one of the three phase windings of the >stator (yellow wires on the connector at the left side). >Regards >JP > > >At 11:07 04/05/2009 -0700, you wrote: >>The induction ammeter has a coil that encircles the wire in question and >>the current going through the wire sets up an electromagnetic field that >>the coil interrupts; strength of current determines voltage induced in >>the coil which the meter displays as amperage. >>Regular ammeter is inline with the flow and measures directly. >>I'm not an electrician but I believe this is accurate; any electricians >>out there, correct if I err... >> >>Stanley554b871.jpg > >> > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en -~----------~----~----~----~------~----~------~--~---
