>Flux density rate of change is related to Voltage
> V = dB/dt
>and
> V = L di/dt
>So
> dB/dt = L di/dt
>Integrating both sides
> B proportional to I
>
? congrats, Jeff.
>
>----- Original Message -----
>From: "Phil (VA3UX)" <phil@vaxxine.com>
>To: <amps@contesting.com>
>Sent: Tuesday, May 07, 2002 7:33 AM
>Subject: Re: [Amps] Rectifier diode strings
>
>
>> At 08:31 PM 5/6/2002 -0700, you wrote:
>> >Yes, that is what I thought also, Jeff. If the flux density doesn't
>> >increase under load, then how is energy transferred from
>> >primary to secondary?
>>
>> No, Tom is correct. Flux density is a function voltage, not current. If
>you
>> look up the voltage equation for transformers you'll see that current is
>> not involved. Ampere-turns is what determines the mmf in the core.
>>
>> Flux density remains essentially constant at all loads.
>>
>> Phil
>>
>>
>> >Mike, W4EF.....................
>> >
>> >----- Original Message -----
>> >From: "jeff millar" <wa1hco@adelphia.net>
>> >To: <W8JI@contesting.com>; "Ian White, G3SEK" <G3SEK@ifwtech.co.uk>;
>> ><amps@contesting.com>
>> >Sent: Monday, May 06, 2002 7:22 PM
>> >Subject: Re: [Amps] Rectifier diode strings
>> >
>> >
>> > > Whoa...flux density comes from Ampere-Turns, not Volt turns.
>> > >
>> > > But, overall an excellent discussion.
>> > >
>> > > jeff, wa1hco
>> > >
>> > > ----- Original Message -----
>> > > From: "Tom Rauch" <w8ji@contesting.com>
>> > > To: "Ian White, G3SEK" <G3SEK@ifwtech.co.uk>; <amps@contesting.com>
>> > > Sent: Monday, May 06, 2002 2:12 PM
>> > > Subject: Re: [Amps] Rectifier diode strings
>> > >
>> > >
>> > > > > Unless I misunderstood Tom's point about mains transformers
saturating
>> > > > > at 1.3-1.4 times normal primary voltage, surely that would only
apply
>> > > > > at full load? The main risk to the rectifiers is more likely to be
>> > > > > during RX periods, when the load is at a minimum but the D >voltage
is
>> > > > > at a maximum. I don't believe the saturation argument would apply
>> > > > > then, would it?
>> > > >
>> > > > Yes, saturation applies. Remember what it is. The core can only
>> > > > obtain a certain flux density, and that flux density relates only to
>> > > > the volt-turn of the magnetizing winding. Flux density is the same at
>> > > > full load or no load, ignoring small differences caused by resistance
>> > > > in the primary and power mains.
>> > >
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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