Claude Lyons / Zenith 8A Variac Refurbishment (Part 4)

Repair and refurbishment of an old 8A Claude Lyons / Zenith variable transformer.
Part 4 - Final electrical testing and checking output voltages.

[kibi]

That was a fantastic little restoration project. Thank you very much for sharing. It's wonderful to see old pieces of equipment given a new lease of life! I really need to get on with my own restoration project, a Tektronix 465B.

[JohnGotts]

The refurb looks great, but the best part is you brought the device up to modern safety standards.

[gandalf]

Thanks for your quick reply. My variac is a bare unit, so I'm contemplating building it into a case, complete with meters to monitor voltage supplied and current drawn by the load.

[darreniii]

Great videos enjoyed them but what i thought was strange was the lack of fuses? Obviously this variac can do 8 amps so in short mode would happily cook wiring any reason for no fuses?

[millomweb]

I noted in earlier videos in the variac series your high mains voltage.
I got up to 259V here and had the local voltage reduced as a result. Light bulbs started lasting longer ! It may have also been responsible for some other failures: boiler transformer and a couple of cameras !
234V today.

[TerryClarkAccordioncrazy]

Is the 253V really a problem? I've used variacs for testing mains appliances that they can work over the full voltage tolerance and in that case it's obviously necessary that the variac can supply the maximum mains even if the incoming supply might be a bit low. Of course such a device needs a bit of care because it can theoretically blow up equipment connected to it if used carelessly.

[robertruth]

Wonderful video and I thank you for making it.

I am curious... I have one and it seems that the shaft is seized as it does not want to turn at all. Do these things generally have bushings or actual bearings of some sort?

[daveissound]

Really enjoyed these vids, great job also.

[donovangreenwood]

Awesome love it!! How long will it run for ?

[jeremytravis]

I was fortunate enough to buy my British made variable transformer new complete with a dial and knob. 
I fitted it into a new rack mount case. It's handy to have the output socket and knob on the same face.
It's still in my workshop today. I did think about installing a volt meter and a US socket. One day maybe.

[dekleinebozewolf]

Very interesting video, trying to get one working myself, but is just wants to flip the circuit breaker when plugging it in. L-N resistance is about 2 ohm, and the is no short to gound, any ideas?

[gandalf]

Excellent videos John, well done! Your refurbishment was first class. I wonder if you could point me in the direction of replacement brushes for this unit as I own the same model and need to source these parts? Supplier name should be sufficient, although a part number as well, would be a great help!

[bobthedino]

Hello, am curious as to whether you came to any conclusions about your rather high mains voltage?

[millomweb]

An analogue meter like that won't give inrush current as it wouldn't respond fast enough. Stick a scope on it ! I'd guess the inrush current would be over 15A.

[staticfanatic]

Has anyone asked about your red power connection block? I haven't seen one of those here in the U.S. .

[copelandaa]

Good project, although 2am is a bit hardcore haha

[millomweb]

5:45 saw the needle move ! (in both directions !)

[elektronikmaleinfach]

i know it before but i have seen a vid its showing very good whats heppend if in a 3 phase system is a problem or a disconect to neutral! i thing under the street is a 3 phase 4 or 5 wire system even if the homes run on singel phase in great britan??? ! in an other vid from you you tell there is some fault in the cable system were you show a massive voltage drop under normal load in the kitchen. !! in my place if i take a look under no load from my side or from the elevator ( in a 80 unit building ) the voltage its alwais near to 230V but under load its dropped massiv! next problem i have is there is massive DC parts on the voltage from a factory next to my place! i thing they use large controled switched recifires for some stuff in a semiconductor factory! so on my projects i have to use DC blockers!:( ist not alowed in germeny to disturb the voltage so much but industry can do what they want! not far on my place there is a large physics reserch center called desy ! i worked at desy xfel for a half jear! they use several hunderts of megawatts an puls mode for the accelerators! they do also a large amount of bad interferance to the grid! :( they have to use motor generator convertors if they do so! people near the complex have sometimes massive problems because of the not good recovery of the symetrical sinus wave! desy have 3 connections of the 3 main substations of hamburg ! they are run directly from 115 000 volts! people at desy tell me if they have not removed the old petra and hera systems they suck more power as an middel sized city alone! but they uses it mostly at some recifires and pulse stuff :(

[elektronikmaleinfach]

teoretical l great britan have no longer 240V nominell ! they have also 230V ! do you thing they have not change anything just change on the paper ??

[elektronikmaleinfach]

these in germany used b16 types circut breaker trips at my home often because i run a pc a sterio amp and other smal things like a monitor on a large switch so if i not use it they are not connectet to the grid! a 500va toridiall transformer with it its over! so i have to use a d20 circut breaker! special these new type of replacmend for the NH fuses into mains 63 amps are shit! they trips faster than a b16 breaker at short circuts and alow not a inrusch current from larger lamps or transformers! i realy like more the old type of melting fuse! i never have problems with the old diazed or neozed fuse or NH fuses! but these circut breakers dont alow me to use heavy tools or power surplys or something else! ! all these stuff is ratet for the circuts i run it on and it dont work!