Go Back   EcoModder Forum > EcoModding > Off-Topic Tech
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 03-10-2017, 05:16 PM   #1 (permalink)
home of the odd vehicles
 
rmay635703's Avatar
 
Join Date: Jun 2008
Location: Somewhere in WI
Posts: 2,590

Silver - '10 Chevy Cobalt XFE
Thanks: 212
Thanked 403 Times in 306 Posts
Cheap 20amp 110vac to 150vac variac where?

Anyone know what happened to the old variacs that can boost voltage?

I'm hoping to find a 20 amp unit with 110vac in and 150vac+ out

Most don't seem to top out around 1:1 in out but those that go into boost are way larger and usually go to full 220vac out, which I don't really need.

Any ideas?

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 03-10-2017, 06:04 PM   #2 (permalink)
Master EcoModder
 
Join Date: Feb 2009
Location: Phoenix
Posts: 595
Thanks: 106
Thanked 112 Times in 70 Posts
There are a number on ebay... 20A units appear to be in the $150+ range but they appear to exist.
__________________
2005 Escape 2.3 MT 2WD
2002 Mustang 3.8 AT
2015 Ram 1500 5.7L 4WD
2002 Motobecane 700DS
  Reply With Quote
Old 03-10-2017, 06:53 PM   #3 (permalink)
V8 guy
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 4,800

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)
Thanks: 103
Thanked 1,125 Times in 824 Posts
I was searching for a bigger version of my 5kw 240v input 300v output auto transformer not that long ago and all I could find were those small 120v in 140v out units on ebay.
Most of the 120v ones are not 20 amp.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
  Reply With Quote
Old 03-10-2017, 09:58 PM   #4 (permalink)
Master EcoModder
 
Stubby79's Avatar
 
Join Date: Sep 2012
Location: Victoria, BC
Posts: 663

Topoff (RIP) - '92 Geo Metro LSi
90 day: 48.54 mpg (US)

'91 Miata - '91 Mazda Miata
90 day: 27.11 mpg (US)

'86 Fiero GT - '86 Pontiac Fiero GT

Purple Penny Pincher - '95 Pontiac Firefly Base
90 day: 43.68 mpg (US)

Jett-Black - '01 Volkswagen Jetta
90 day: 39.32 mpg (US)

Firefly EV - '98 Pontiac Firefly EV
90 day: 108.06 mpg (US)
Thanks: 32
Thanked 205 Times in 149 Posts
Do you need a set voltage, or an adjustable one?
__________________

  Reply With Quote
Old 03-10-2017, 11:13 PM   #5 (permalink)
V8 guy
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 4,800

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)
Thanks: 103
Thanked 1,125 Times in 824 Posts
For lower voltage I just rewrap the secondary on microwave oven transformers.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
  Reply With Quote
Old 03-11-2017, 11:43 AM   #6 (permalink)
home of the odd vehicles
 
rmay635703's Avatar
 
Join Date: Jun 2008
Location: Somewhere in WI
Posts: 2,590

Silver - '10 Chevy Cobalt XFE
Thanks: 212
Thanked 403 Times in 306 Posts
Quote:
Originally Posted by Stubby79 View Post
Do you need a set voltage, or an adjustable one?
Honestly a set voltage would be fine, but sadly I need to find what it is. (It's between 140-160 volts) the 220vac output variacs seem to be much larger and more expensive than I would prefer..

The 140 volt units seem to not go past 1:1 which makes them useless to me.

Being able to put in either 110vac or 220vac and get around 150 would be nice but not necessary.

Thus far there only seem to be 2 main styles of variac and the ones that boost aren't in those common categories.

Ah well
  Reply With Quote
Old 03-11-2017, 12:57 PM   #7 (permalink)
ScanGauge <3
 
Join Date: Dec 2016
Location: CID
Posts: 291

Winter Sacrifice - '96 Subaru Outback
Subaru
90 day: 25.89 mpg (US)
Thanks: 153
Thanked 96 Times in 68 Posts
150ish volts at 20 amps is a lot of watts! What are you looking to do?
__________________



Best tank (so far): 32 MPG
  Reply With Quote
Old 03-11-2017, 02:19 PM   #8 (permalink)
Master EcoModder
 
Stubby79's Avatar
 
Join Date: Sep 2012
Location: Victoria, BC
Posts: 663

Topoff (RIP) - '92 Geo Metro LSi
90 day: 48.54 mpg (US)

'91 Miata - '91 Mazda Miata
90 day: 27.11 mpg (US)

'86 Fiero GT - '86 Pontiac Fiero GT

Purple Penny Pincher - '95 Pontiac Firefly Base
90 day: 43.68 mpg (US)

Jett-Black - '01 Volkswagen Jetta
90 day: 39.32 mpg (US)

Firefly EV - '98 Pontiac Firefly EV
90 day: 108.06 mpg (US)
Thanks: 32
Thanked 205 Times in 149 Posts
Quote:
Originally Posted by rmay635703 View Post
Honestly a set voltage would be fine, but sadly I need to find what it is. (It's between 140-160 volts) the 220vac output variacs seem to be much larger and more expensive than I would prefer..

The 140 volt units seem to not go past 1:1 which makes them useless to me.

Being able to put in either 110vac or 220vac and get around 150 would be nice but not necessary.

Thus far there only seem to be 2 main styles of variac and the ones that boost aren't in those common categories.

Ah well
You can use an isolated AC source to add it's voltage to another AC source, as long as they're in phase with each other...

...meaning if you had a 120v to ~30V AC transformer, you could put it in series with the 120v from the outlet, and the two will add together to give you 150v AC. As per this informative article (which I would not recommend for complete novices to follow):
Battery Charger Schematic (Bad Boy)

You could also use an isolation transformer instead of straight-from-the-wall power to completely isolate it. Or combine a variac with an ~30v (isolated) transformer to give you the ability to alter the voltage.

Please note that a variac IS NOT ISOLATED...and trying to combine it in series with it's own source will end in the apocalypse...at least as far as you and anyone in the room with you is concerned anyway. Wasn't there something about not crossing the streams in ghost busters? Well, this won't have a happy ending...

Be safe! (and if you don't need this warning, well, some people out there reading probably do)

BTW, what are you trying to accomplish?
__________________

  Reply With Quote
Old 03-11-2017, 04:45 PM   #9 (permalink)
Adrift in the slow lane
 
RedDevil's Avatar
 
Join Date: Dec 2012
Location: Nieuwegein, the Netherlands
Posts: 2,125

Red Devil - '11 Honda Insight Elegance
Team Honda
90 day: 58.6 mpg (US)

It - '09 Hyundai I10 Active Cool
Team Hyundai
90 day: 31.16 mpg (US)
Thanks: 748
Thanked 838 Times in 539 Posts
The reason you don't see many variacs around anymore is that for most appliances you get better control and efficiency with a triac which is cheaper too.
As a driver for brushless motors, not so much. But otherwise I'd go with the 220 Volt transformer, then bring it down to your desired voltage with a triac.
__________________
2011 Honda Insight + HID, LEDs, UG, partial LGB, extra brake pad return springs, neutral wheel alignment, 44/42 PSI (air), PHEV light (inop).
lifetime FE over 0.1 GigaMeter or 66 KiloMile

  Reply With Quote
Old 03-11-2017, 06:07 PM   #10 (permalink)
home of the odd vehicles
 
rmay635703's Avatar
 
Join Date: Jun 2008
Location: Somewhere in WI
Posts: 2,590

Silver - '10 Chevy Cobalt XFE
Thanks: 212
Thanked 403 Times in 306 Posts
Quote:
Originally Posted by ThermionicScott View Post
150ish volts at 20 amps is a lot of watts! What are you looking to do?
Actually, my source will be a 20 amp outlet the output will use a max of 12 amps.

So I shouldn't exceed 16 amps on the supply side (even with losses)

  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com