Variac

[Multi-Volti Devices]

back to back xfmrs works, but the regulation stinks...I'm not sure why,
unless magnetizing current in the second one isn't right (just a guess).

I used a pair roughly 200 - 250VA xfmrs with 24V-ish secondaries back-back
to isolate an oscilloscope monitoring fluorescent lamp start voltage @ 3 kV
p-p...I only got about 105 V to scope...luckily it was a universal switching
supply 85-260 V input!

Murray
----- Original Message -----
From: "Jim Berry" <basalop at gte.net>
To: <HEATH at LISTSERV.TEMPE.GOV>
Sent: Tuesday, June 05, 2001 2:44 PM
Subject: Re: Variac


> >
> > Variac's (AKA autotransformers DO NOT PROVIDE ELECTRICAL
> > ISOLATION!!!
> > Mark Hughes  WB4UHI
> >
>
> Want to make a low buck isolation transformer?  Take two of your old
> filament transformer and wire them up back to back.  115 to say 5.0
> volts.  Hook up the next 5.0 volt transformer winding to the other
> transformers 5.0 volt winding, and you have isolation.
>
> 73 Jim K7SLI
>
>
>
> ---
> Outgoing mail is certified Virus Free.
> Checked by AVG anti-virus system (http://www.grisoft.com).
> Version: 6.0.256 / Virus Database: 129 - Release Date: 5/31/2001
>
> Listserver Subscription:listserv at listserv.tempe.gov - "subscribe heath
'name' 'call'"
> Listserver Submissions: heath at listserv.tempe.gov
> Listserver Unsubscribe: listserv at listserv.tempe.gov - -"signoff heath"
>

Listserver Subscription:listserv at listserv.tempe.gov - "subscribe heath 'name' 'call'"
Listserver Submissions: heath at listserv.tempe.gov
Listserver Unsubscribe: listserv at listserv.tempe.gov - -"signoff heath"