• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

My VARIAC

thefragger

thefragger

Certified Crazy.
I finally wrapped up this project! I put in a 120v neon power indicating lamp in parallel with the wall plug, there's also a fuse before the switch on the hot wire. On the opposite side of the traffo we've got a switch which puts power right to the pigtailed outlet, or send the power to a set of banana posts for use with an ammeter to measure current or the device that's plugged in.

​
:thmbsp:
 
Last edited:
Register to hide this ad
The ammeter is essential for first-time power-up - I have a Kill-a-Watt meter plugged in to my bench variac for that purpose.
 
Tom Bavis said:
The ammeter is essential for first-time power-up - I have a Kill-a-Watt meter plugged in to my bench variac for that purpose.
Click to expand...

+2

attachment.php


Steve
 
Nice work, Philip. Reminds me to get working on mine.
Paint bucket, eh, I think I can do a little better but it is intriguing.
 
westend said:
Nice work, Philip. Reminds me to get working on mine.
Paint bucket, eh, I think I can do a little better but it is intriguing.
Click to expand...

Thanks, Lance! I'm loving that Weller I got from you--bought a set of new tips and it's a dream to work with!! :banana:

The paint can in an interesting form factor, I have to say, for maybe a 10~20A capacity device! :thmbsp:
 
westend said:
Nice work, Philip. Reminds me to get working on mine.
Paint bucket, eh, I think I can do a little better but it is intriguing.
Click to expand...


I needed a variac ASAP and ended up with this. The bucket is plastic.

attachment.php


One thing to remember about a "Kill-A-Watt", you have to have about 40+ watts input for it to register on the LCD.


Steve
 

Attachments

  • variac_can.JPG
    variac_can.JPG
    72.5 KB · Views: 780
Wayniac said:
Nice job. I personally would have fused the unit prior to the power switch.
Click to expand...

I think that that's what I did too, but then drew the schematic wrong--you can see the hot wire go over to the fuse, then a red wire from the fuse to the switch before attaching to the primary.
 
Nice work Folks!

I agree that they are not really useful without a meter. Here is one I built a few years ago from junk I had laying around. Since then I bought a Sencore PR57. I highly recommend this unit as it feature leakage detector, an internal isolation tranny and circuit breaker instead of a fuse. Very nice.

Just in case someone reads this thread that is a novice. A variac does nothing to protect you from the equipment you still need couple a variac with an isolation tranformer for safety.

Steve

attachment.php

attachment.php

attachment.php
 

Attachments

  • IMG_4635.jpg
    IMG_4635.jpg
    55.9 KB · Views: 157
  • IMG_4636.jpg
    IMG_4636.jpg
    98.2 KB · Views: 156
  • pr57.jpg
    pr57.jpg
    50.8 KB · Views: 156
thefragger said:
Thanks, Lance! I'm loving that Weller I got from you--bought a set of new tips and it's a dream to work with!! :banana:

The paint can in an interesting form factor, I have to say, for maybe a 10~20A capacity device! :thmbsp:
Click to expand...

Always nice to hear someone is enjoying my surplus items :D

The paint can variac is definitely sweet, I always like to see alternative, inventive ideas.:thmbsp:

That Sencore is drool-worthy. I so need to upgrade my test gear.
 
You must log in or register to reply here.
Back
Top Bottom