Transformer DC resistance value estimate needed

bitrex

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Mar 31, 2019, 5:13:06 PM3/31/19

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Can anyone give me a ballpark on the DCR of this particular
small tube-PSU-type transformer to plug into PSU Designer II?

<https://www.alliedelec.com/product/hammond-manufacturing/6k88vg/70009014/>

<http://www.duncanamps.com/psud2/>

Fox's Mercantile

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Mar 31, 2019, 7:14:58 PM3/31/19

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You can ask Hammond directly.
us-...@hammondmfg.com

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http:foxsmercantile.com

Phil Allison

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Mar 31, 2019, 8:22:32 PM3/31/19

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bitrex wrote:
>
>
> Can anyone give me a ballpark on the DCR of this particular
> small tube-PSU-type transformer to plug into PSU Designer II?
>
> <https://www.alliedelec.com/product/hammond-manufacturing/6k88vg/70009014/>
>
>

** Assuming the tranny has a regulation factor of 10%, that equates to 6 volts copper loss on the primary under full load.

Rated load is 36 VA plus a little for Imag gives 40VA.

So the primary current with resistive load is 0.33amps rms.

Makes the primary R = 18ohms.

A similar, 240V tranny would have four times the primary R.

..... Phil

John Robertson

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Apr 1, 2019, 2:57:18 AM4/1/19

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On 2019/03/31 4:14 p.m., Fox's Mercantile wrote:
> On 3/31/19 4:13 PM, bitrex wrote:
>> Can anyone give me a ballpark on the DCR of this particular
>> small tube-PSU-type transformer to plug into PSU Designer II?
>>
>> <https://www.alliedelec.com/product/hammond-manufacturing/6k88vg/70009014/>
>>
>>
>> <http://www.duncanamps.com/psud2/>
>>
>
> You can ask Hammond directly.
> us-...@hammondmfg.com
>
>

Mouser has an ECAD model info on that transformer - but no stock:

https://www.mouser.ca/ProductDetail/Hammond-Manufacturing/6K88VG?qs=BJ2NLfHFoSmozu4alfnsEA==

Here is the Hammond classic xformer page:

https://www.hammfg.com/electronics/transformers/classic/200

Looks like 269JX is close to the 6K88VG.

John :-#)#

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bitrex

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Apr 1, 2019, 11:42:51 PM4/1/19

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Great, thank you, seems to be in congruence with the similar
Hammond-branded specs on the 269JX JD referred above, rated for 60mA
output with around 11 ohms primary DCR and 350 ohms on the secondary.

<https://www.hammfg.com/files/parts/pdf/269JX.pdf>

A pretty nice piece for the price I think particularly given that I
should be able pick up several in person at the warehouse and avoid
shipping.

Only question I'm unsure of now is what format the program expects the
transformer "source resistance" parameter in; whether it's the
end-to-end secondary DCR plus the primary DCR referred to the secondary
directly, or whether that needs to take into account in a full-wave
center-tapped configuration that the load is only "seeing" half the
secondary impedance at a time, unfortunately the included Help manual is
not helpful here.

bitrex

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Apr 1, 2019, 11:45:09 PM4/1/19

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I suppose this is technically a design issue but sci.electronics.design
makes fun of tubes. they think they're too GOOD for tubes. :(

Look165

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Apr 2, 2019, 4:30:39 AM4/2/19

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Me, I would measure it with an ohmmeter (=> copper resistance) and then
shrtocut the secondary and apply the adequate voltage at the primary so
that the secondary current is OK
and measure the primary current (=> the iron resistance).

This give copper loss and iron loss.

bruce2...@gmail.com

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Apr 5, 2019, 11:36:42 PM4/5/19

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On Monday, April 1, 2019 at 2:57:18 AM UTC-4, John Robertson wrote:
> On 2019/03/31 4:14 p.m., Fox's Mercantile wrote:
> > On 3/31/19 4:13 PM, bitrex wrote:
> >> Can anyone give me a ballpark on the DCR of this particular
> >> small tube-PSU-type transformer to plug into PSU Designer II?
> >>
> >> <https://www.alliedelec.com/product/hammond-manufacturing/6k88vg/70009014/>
>
> >> <http://www.duncanamps.com/psud2/>
>
> > You can ask Hammond directly.
> > us-...@hammondmfg.com
>
> Mouser has an ECAD model info on that transformer - but no stock:
>
> https://www.mouser.ca/ProductDetail/Hammond-Manufacturing/6K88VG?qs=BJ2NLfHFoSmozu4alfnsEA==

Mouser Sponsors Formula E All-Electric Racing for 5th Year
-- https://finance.yahoo.com/news/mouser-sponsors-formula-e-electric-202000399.html
Feb 5, 2019 - Mouser Electronics, T