DEC H7822 power supply

Paul Koning paulkoning at
Fri May 13 09:04:37 CDT 2022

> On May 13, 2022, at 3:36 AM, Christian Corti via cctalk <cctalk at> wrote:
> On Thu, 12 May 2022, Peter Coghlan wrote:
> ...
>> A variac does not provide isolation.  If it is not wired correctly, it is
> Good "variacs" provide galvanic isolation from the mains, i.e. they are not autotransformers.

There may be variable transformers that aren't autotransformers, but I've never seen one.  The commonly seen Variac devices (either that brand, or analogous devices from other makers) are autotransformers.  

It should be obvious by inspection which kind you have, and take precautions as needed.


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