VARIAC MAINTENANCE

[Roger Borg]

Patience has paid off, and I have been able to pick up a proper variac at a reasonable cost.

When purchased, plugged in a sabresaw and dialed up and down, and it slowed and sped up. Didnt have a 3 prong adapter to go into the 2 prong variac for my killawatt, so that test was my only reassurance. 

That said, just as I wouldn't put a working fan into rotation without giving it a once over, I don't want to throw this into action without some attention. 

That said, i have no idea where to start or what to look for. Any advice on upkeep and general maintenance on one of these? Initial and ongoing?

General radio variac, type v10

Also, what are the M and T tabs alongside the V10?

As always, all input is greatly appreciated...

[Dave Hoatson]

Note that when plugged into modern 120 volt outlets, a Variac may have a higher output voltage than what is indicated on the dial. 
 

For driving 104 bolt fans, I ordered a couple 120 -> 100 volt converters that are designed to run Japanese appliances in the US. These are smaller and cheaper than a Variac. 
 

 

 

 

Plugs into the wall and allows slower speeds:

[Roger Borg]

23 minutes ago, Dave Hoatson said:

Note that when plugged into modern 120 volt outlets, a Variac may have a higher output voltage than what is indicated on the dial. 
 

For driving 104 bolt fans, I ordered a couple 120 -> 100 volt converters that are designed to run Japanese appliances in the US. These are smaller and cheaper than a Variac. 
 

 

 

 

Plugs into the wall and allows slower speeds:

Understood, I planned to put a killawatt on it to confirm proper voltage gets to the fan. I never trust dials alone.

That said, I'm still looking for advice on initial maintenance before using. Thanks...

[Dave Hoatson]

Variacs tend to be very simple and reliable. I would check to make sure that all switch contacts read less than one ohm.