As my wife is getting me a variac for Christmas I have been watching many videos on them, and yours gave me a good insight into perhaps future problems and how to maintain it. 👍
@beakytwitch7905
2 жыл бұрын
I used a brass brush on a Dremel to clean the copper surface and sweep between the windings. Did the job.
@larryzimmer1350
5 жыл бұрын
There is another contact which may have contributed to the connection problem. Starting at 5:20 there is a closeup of the top of the autotransformer. On the right is the wiper contact which runs along the windings and it is connected to a metal disk below the white disk on the shaft. On the left there is another contact which runs from the edge to the bottom of the metal disk. That second contact slides along the underside of the metal disk and completes the connection from the wiper contact to the output wire of the autotransformer. That contact could have been worn, or the disk dirty, or pitted. It would have been a good idea to completely remove that wiper/disk assembly from the shaft and had a look at the underside of the disk, and that second contact.
@12voltvids
5 жыл бұрын
I did a full overhaul on this about a ear after the video when it started acting up again, and it was really bad. It was featured in my award winning deoxit commercial.
@therealjammit
6 жыл бұрын
My first variac was given to me by a college. It was overloaded and burned out. When I took it apart I found out the windings were seriously smoked and useless. I actually rewound it with new magnet wire, sanded the tops (like you did), and put it back in service.
@dell177
5 жыл бұрын
I bought a case mounted 10A variac in a metal case from a coworker with volt and amp panel meters in the early 70's. We were working for a power supply company that had it's pwn transformer division so I got a 500w isolation transformer wound and mounted it in the case so now I have an isolated variac. Last year the voltmeter died, I've lost more than one panel meter to oxidation in the cellar (tends to got a bit humid) so I picked one up on ebay and popped it in after dragging the mounting holes with my drill. i should start looking for a new brush assy for thatStaco varic because at 48 years old it has to be worn.
@jerryspann8713
7 жыл бұрын
Simular to a race track speed controller, used in old tyco race car tracks. I took one apart as a child, and there was a coil of wire and a copper sweeper connected to the trigger, and when you pulled the trigger the copper sweeper would move accross the coil increasing or decreasing speed of race car. Simular principal in an electric train power pack.
@zx8401ztv
7 жыл бұрын
Smashing, nicely recovered and ready for use again :-) Its just too usefull a device to be out of service, its like your esr meter, it has to work. I was given a variac to repair over 20 years ago, a couple of the wires wore through. i dug out the dead wires from the laquer, and fitted new enameled wire of the same diameter. Joints were made down the side and near the center of the transformer, after the new laquer had sat for a week, i slowly filed the new wire flat to line up with the original height. Saved a rather expensive device at the time :-).
@12voltvids
7 жыл бұрын
Yes they are a few bucks.I plan to do a demonstration on that Toshiba CRT tv on a future video.Plan to fux up the B+ regulation so the set goes into OVP shut down, and then use the variac in the troubleshooting.
@12voltvids
7 жыл бұрын
This set is a linear regulator.Want to show the symptom of loss of regulation, and how a variac will help TS this. I have covered this before with a different set that had a regulation problem, but not a total failure but I guess I have to clean up my test bench first to keep the trolls at bay. Apparently I have no credibility due to the odd typo on a file name, or pronunciation of a word. I have trolls telling me that solder is really sodder. Well perhaps for the Chinese that can't say the letter L it is.
@zx8401ztv
7 жыл бұрын
I dont really understand trolls, what has your bench got to do with your ability to repair things, tell them to piss off. soder is the american spelling and really is nit picking. I have a small reel of desolder braid and it has the american soder spelling, i dont really care how its spelt, as long as it works :-)
@12voltvids
7 жыл бұрын
zx8401ztv that and the troll that said because I pronounced oxidation "oxidization" which is how it was pronounced way back in the 70s when I was in high school. said I have no credibility. oxidization last time I checked means the same thing. a material loosing electrons in the presence of oxygen. when iron is left in the presence of oxygen it oxidizes into iron oxide, better known as rust. that Brown stuff we glue onto plastic film and use for recording magnetic signals on, tape
@mrjohhhnnnyyy5797
7 жыл бұрын
Don't bother cleaning your bench, trolls will find another reason to harass you. If you do real repairs the bench will be a huge mess, and it's normal. Your bench is just fine, there's plenty of space on it to put a TV :) About the credibility - I see the skills when you do repairs, that's enough for me to not think about credibility. Anybody who really does repairs would be able to tell. Each repairman has his style, and that's completely OK if you ask me.
@ao2528
5 жыл бұрын
The bottom of the control shaft have a nut and washer, over time they became loose causes larger gap between carbon brush and the variac coil, you can solve such a problem by tightening the bottom nut since I noticed plastic ring of carbon sweeper were at its original spot and they weren't loose.
@DarrellRoper
7 жыл бұрын
Everything wears out. Glad you able to give this some new life.
@frankreiserm.s.8039
5 жыл бұрын
I built a high-quality, very strong (can take a lot of weight) bench. On top of the bench, I have a white-painted perfboard surface. When the top of the bench gets too marred up, I simply turn the board over.
@ArcadiaStudiosCHS
7 жыл бұрын
I've seen machinists use ScotchBrite pads for polishing as well as emery cloth. I wonder if that would have worked as well. I first thought about steel wool but you probably wouldn't want small iron filings left behind. Thanks for sharing.
@12voltvids
7 жыл бұрын
That would cause a spark show for sure. That's why I used aluminum oxide paper.
@medusa569
4 жыл бұрын
On my variac I'm not getting power output until i'm about 3/4 the ways around. Don't see any particular off coloration or broken /loose wires... What might be the problem?
@jonka1
5 жыл бұрын
Might have been worth taking out the shaft and lubicating it as it looks to be wear in the thrust faces that caused this.
@herbertprince2192
7 жыл бұрын
I had never heard of a Variac until a few days ago, when I saw one on You Tube. Will a PHC Enterprise SC-3M Variac Variable Transformer, 300 VAC Max, 0-130V Output, 3 Amp, connected to a piece of 20 gauge Nichrome 80 Resistance wire cause it to glow orange for 5 to 6 minutes at a time, or would I need a larger Variac unit? Am interested in building an acrylic plastics bender. Can't seem to find anyone who knows the answer to this question.
@umajunkcollector
7 жыл бұрын
what do you think about using a contact cleaner with spray lubricant on it?
@DAVIDGREGORYKERR
7 жыл бұрын
I am surprised that no one has developed a computer controlled Variac using a R2R network to control the voltage.
@walker55able
2 жыл бұрын
Great thanks for this really interesting
@Totogita
4 жыл бұрын
Thanks for posting this I learned a lot.
@redemptusrenatus5336
7 жыл бұрын
Glad to see the variac didn't end up totally burnt out. I've got an old Superior Electric Powerstat on my bench which works great. Very interesting how you cleaned yours up. I thought there might have been a problem if you sanded it but as you said you weren't putting a lot of elbow grease into it as it was only to clear the grime off and not actually polishing up the copper. I thought perhaps contact cleaner could work but not sure if it would try to eat through the glue/coating that's on the coil? Any thoughts?
@12voltvids
7 жыл бұрын
Redemptus Renatus I did have to sand a bit. was a pitted area. aluminum oxide grit was used. very fine so as not to scratch. working great now.
@redemptusrenatus5336
7 жыл бұрын
12voltvids There was a definite improvement in conductivity after the cleaning you gave it. That light bulb was shining bright for sure. Not bad after ten years of abuse eh? :D
@robbieaussievic
7 жыл бұрын
....... New intro passes the cool test .
@Felix2417425
7 жыл бұрын
19:25 so that's the click which is heard every time you switch-off the power. I always wondered where you have relay, I thought it's in the variac.
@12voltvids
7 жыл бұрын
Yes. The power strip has a protection relay that cuts power if too high or too low.
@caldasauletedicionario2863
Жыл бұрын
thank for sharing!
@surgingcircuits6955
7 жыл бұрын
So, now it's a "Varic" vs "Variac"? HeeHee Hey, love your repair vids. Just ordered my first variac - same as yours, only the 5A version. Question, do you have a video up where you're putting the variac to use for a purpose (repairing or whatever) vs just demoing the variac itself? What all do you normally use it for yourself? Do you have stuff that wants less than 120VAC? Or, do you supply lower VAC when working on things to lessen the pressure on a power supply, or lower risk - do you know what I mean? Lastly, I'm told this China unit doesn't have the case grounded - could you talk about that and isolation? Don't want much, do I! (HaHa) Great stuff, man.
@12voltvids
7 жыл бұрын
I have a sticky keyboard on my editing pc. The "A" key doesn't resister unless I hit it hard. That is how the file name went in, and I forgot to change the filename when I uploaded it, and youtube uses the filename as the description until I go in and change it. Notice it was CORRECT in the description.
@surgingcircuits6955
7 жыл бұрын
12voltvids So, I'll make some guesses on your applications... If you work on vintage stuff (especially amps) or bias an amp, you reduce to 117v. Fire up something old or something not powered for a while, use it to spare the capacitors a sudden jolt. Test Japanese items designed for 100v use in Japan. After a repair, bring up on lower-to-nominal voltage to see if anything's complaining as volts increase. Off the bench, maybe slow a fan or other motor. Any other tricks-of-the-trade voltiac uses?
@12voltvids
7 жыл бұрын
That will be the next vid. I was going to shoot it today, but a modem swap in anticipation of putting in a bonded loop next week had me fighting network troubles all night. Who would think swapping a modem would take 5 hours. Should have done it during working hours when I would have been paid for it.I am still fighting with my security cameras. I can view them when connected to the cellular network, but I can not connect to them when I am on my own Wifi network. Blows my mind, because my DVR has an external IP address, not on my network. It is on a bridged port, so it shouldn't matter if I am on my wifi, or on the cellular network. My router has an public IP, and my security cameras also has a public IP. Anyway the variac demo video will be shot in the next day of so. I am going to create some regulation faults on a TV, to show the real use of a variac when a device is going into shutdown due to loss of regulation, and how lowering the input voltage will allow the unit to run for troubleshooting.I am going to create 2 separate faults, an over voltage, and an undervoltage situation, which were common uses of variacs for troubleshooting.Looking forward to my new internet connection, as my upload bandwidth will double, which will be very useful for uploading. That goes in on Monday.Have it all set up already, already ran in jumpers, connected the 2nd pair drop, and installed the modem. So on Monday I plug in the second line, and flow the order.
@12voltvids
7 жыл бұрын
The biggest use for variacs in troubleshooting linear regulators in old analog TVs. The TV typically used a 135V regulator. When AC is rectified the main cap charges to about 170V.The voltage is dropped with a shunt resistor, that will drop it to about 100 or so volts by itself, and then a regulator transistor is placed across the shunt that can vary the voltage to whatever the set requires. This feeds into the flyback, where all the other lower voltages and HV is made.Now, the voltage must be stable, because if it goes too high, the HV will really go high and the CRT could start to make XRays. That's a bad thing. So there is a monitor circuit to shut the set down if the voltage goes too high.Should the regulator circuit fail, and the voltage goes up the set will shut down. The variac can be used to run the set on low voltage, so it can be run without shutting down, so voltages can be measured to find the bad part.That will be the demo. I will disable the regulator so the voltage goes high, and the set shuts down at normal 120V.
@VidelicetMoi
5 жыл бұрын
A bit of dialectic grease along the topside of the coil would aid in inhibiting wear. And don't buy Chinese in the first place. You get what you pay for.
@12voltvids
5 жыл бұрын
A year and half later still working perfect.
@rbmwiv
5 жыл бұрын
12voltvids Didn’t you say at the beginning that you have had it for 10 years before issues. I have the almost same one. Looks identical except mine has 2 plugs and is 10a. I don’t see any problem with the Chinese variacs. They are built pretty much like the rest of them and they are easily serviced. I have had mine for a year and no issues. I just need a bigger isolation transformer mine is only 6 amps. It’s weird. It’s repurposed from some piece of old equipment. I don’t know what from. Bought used for a steal, just had to re wire it because it still had the factory wiring that had different plugs.
@infinitecanadian
5 жыл бұрын
Do you recycle all your components including the capacitors? I can't imagine it would be good for electrolytics to go into the environment.
@carlubambi5541
Жыл бұрын
Some times the brush itself needs a little sanding
@CondorAudio
6 жыл бұрын
Sandpaper (in any mix or form) should be used only as a very last resort. The correct non-abrasive stuff to use is good-old British Empire BRASSO, which has been around for over 100 years. It cleans it perfectly, without even the tiniest scratches. AND you wouldn't have ANY carbon residue left at all. You're simply working too hard to find that bad spot, and with Brasso, you'd have solved it long ago.
@adrinathegreat3095
5 жыл бұрын
Or T-cut which is essentially the same product but more expensive
@simont3686
4 жыл бұрын
I just bought one a few days ago. Arrived today, plugged it in and it hummed very loudly. Blew its fuse within half a second. I have to say that the variac is a 110V one and I ran it on 230V. But that shouldn't matter right? Do you know what I could have done wrong? Does a load have to be connected? Can you help?
@12voltvids
4 жыл бұрын
The problem is you plugged a transformer wound for 110 volts into 220. Yes they are different.
@simont3686
4 жыл бұрын
@@12voltvids How are they different?
@12voltvids
4 жыл бұрын
@@simont3686 The number of turns on the transformer winding.
@simont3686
4 жыл бұрын
@@12voltvids How does that matter?
@vlwilbert
7 жыл бұрын
ANOTHER GOOD VIDEO. COULD YOU HAVE PUT ANOTHER WASHER ON THE WIPER TO MAKE BETTER CONTACT.
@12voltvids
7 жыл бұрын
Not needed. Lots of adjustment left on that wiper shaft.
@AIexanderHartdegen
7 жыл бұрын
ok how can we see the sea on your workbench??? This is kind of magic?
@12voltvids
7 жыл бұрын
I do moving photos as projects, which are just ultra HD videos of scenery. Some are up on YT. I usually have the TV on when I am working, so I switch it over to content I have created when I am recording so that the image in the background doesn't pull a content ID match. I sell versions of the youtube samples (they are not the same versions, in fullHD or ultra 4K without any watermarks)
@AIexanderHartdegen
7 жыл бұрын
12voltvids it's amazing I like it very much. in the first time I thought you were in fron of ocean. It gives lot's of oxygen in the mind.
@12voltvids
7 жыл бұрын
I am very close to the beach. I can see it from my bedroom window. The videos are of Tofino and the Oregon coast.
@AIexanderHartdegen
7 жыл бұрын
12voltvids that's nice!
@dvddale111
5 жыл бұрын
What no earth or ground on your house wiring?
@robpeters5204
5 жыл бұрын
I bought one like that last year in k2018. And it's one of those cheap Chinese built ones I guess. Got it out of the box. Plugged it in and when I turned it on it tripped my breaker and popped the fuse inside the variac. I sent it back right away. Scared the crap out of me.
@radioflyer9959
4 жыл бұрын
Been looking at the Chinese ones also but ended up with a staco pf1010 that is like new and very high quality.
@Cp0455
5 жыл бұрын
I bought a variac and it’s smoking and stinking right out of the box. Took it apart and the coils are jacked and there’s something burning up on them. Is there any way I can send you pics and ask for help?
@bones007able
7 жыл бұрын
Chinese... half the price of a well built one, I had one of those too , was never right . the voltage on the little meter never matched what the top said or what my VOM read... all three were different , so which one do you believe then?
@12voltvids
7 жыл бұрын
The meter is pretty close. You are right they are cheap. That one was under 100 bucks. It is usefull in power supply testing, so that voltage can be boosted or dropped. As long as I know where 120 is, and I marked it.
@HDXFH
5 жыл бұрын
Chariac lol wouldn't surprise me if it has aluminium windings on some that come from there
@ronniezzzz
7 жыл бұрын
have you seen mr photons variac setup
@12voltvids
7 жыл бұрын
ronniezzzz yes I think we have all seen it complete with the release mote control and the air control foot switch. pretty impressive for sure. great for roasting things. mine is a service aid for power supply work.
@12voltvids
7 жыл бұрын
ronniezzzz yes I think we have all seen it complete with the release mote control and the air control foot switch. pretty impressive for sure. great for roasting things. mine is a service aid for power supply work.
@mialara2590
7 жыл бұрын
Sorry but no, that is not a percentage scale, that is a volt scale. It is clearly stated below the voltmeter that the unit has 0-130 volt output, and you showed us that at full rotation it gave 130 volts output! I guess the variac is not perfectly linear and might output 120 volts when set to 100 but that is just a coincidence since that is not a percentage scale.
@12voltvids
7 жыл бұрын
Nope, it is a percentage scale. In case you didn't notice that the "100" mark already had a black sharpie line where I marked it back when I got the unit. The labeling shows 0 to 130, but it is NOT what is marked. The meter is accurate. I put the sharpie mark on it so I would know where 120 was so I could power it up at 120. I did go back, on video @ 18:09 and adjust the dial so it was pointing to 0 when it is turned to 0, and at 100 it is outputs between 115 and 120 on the meter. Remember this is a cheap Chinese variac.
@mialara2590
7 жыл бұрын
Had a chance to check a coworkers unit, same unit as yours, and my own unit which looks exactly the same but is higher wattage. We both agreed it is not a percentage scale and did some testing, if your unit outputs 120 volts at the 100 marking it is due to the fact that the nominal input on this units is 110 volts and in Canada you must be inputting at least 120 volts or more, and maybe due to bad calibration also. We connected my friends unit to the output of my unit dialed in to output 110 volts (checked with a multimeter) and at the 100 mark his unit outputted 102 volts. Wired them the other way around and my unit at the 100 mark outputted 99 volts. It is a volt scale calibrated at the nominal 110 volt input, and +/- 2% precision sounds pretty good to me considering how cheap this units are!
@HDXFH
5 жыл бұрын
Not much to go wrong unless you're photonicinduction
@12voltvids
5 жыл бұрын
Speaking of him. Havent seen anything from him in years.
@dylanreischling4151
5 жыл бұрын
Do you know where to find a quality variac anywhere?
@jstro-hobbytech
2 жыл бұрын
I bet it still works today ehh
@12voltvids
2 жыл бұрын
Everything on my bench under test runs through isolation transformer and then to variac then to power bar.
@jstro-hobbytech
2 жыл бұрын
@@12voltvids yes, I know, I've watched your great video on the set up manh times to inform thr way mine will be installed. I meant the variac still works as I can't recall ever seeing you fail a fix when you've take into account your time worth in money to effort. I've always meant to ask. You must have some home theater sound set up. I know you're spoiled for choice when it comes to hifi audio but I mean as afar as having a smoking Dolby atmos set up haha. I Ramble sorry but I have great respect for your skill and no nonsense humor where people think you're serious and that's part of the joke.
@12voltvids
2 жыл бұрын
@@jstro-hobbytech actually you would laugh at my setup. It is a very old Onkyo receiver. My tv is a 13 year old 63 plasma. I don't even have my sub plugged in. I don't watch much in the way of movies so don't need anything fancy. The only reason i have a 4k tv in the studio is for checking my content for quality. My 2 channel systems are much better. I am more a music guy not so much tv.
@jstro-hobbytech
2 жыл бұрын
@@12voltvids we share alot in common haha. I have a home studio for recording original music, a 6k diy gaming rig, an LG c9 with ps5 and I'd trade it all for my old 3d plasma. My soldering iron and cmos/ttl ic collection, breadboards and leds get 90 percent of my time. I haven't used the oled in a year or watched a TV show in about 6 years and if I do it's a Deadwood, the Wire or Oz rerun lol I've accumulated close to 100 thousand leds of all types and shapes yet everything I make I give away or if it's an elaborate breadboard experiment I take a picture before I disassemble it all to be used again. I love doing things with passive components and logic gates that people have to use arduinos for. I donate arduino kits to underprivileged kids, others with mental illness and schools. I had a small 3d printing business thing going last year and sunk all the prophits into arduino kits, multimeters, soldering irons and practice kits for people. I plan to become a patron of yours very soon as well.
@timeillusion4581
7 жыл бұрын
👍🏼👌🏼
@craneoperator4
7 жыл бұрын
chinese rheostat
@markanderson350
7 жыл бұрын
Made in Jhina is the issue. LOL
@12voltvids
7 жыл бұрын
I should get photonicinduction to send me a British made Variac. That will never fail. (If you have seen the abuse he puts his through)
@markanderson350
7 жыл бұрын
That guy is a maniac. So that's who influenced your frydom
@12voltvids
7 жыл бұрын
He likes to blow stuff up. :)
@markanderson350
7 жыл бұрын
Yes with 19 Gigawatts of power. He blew up his electric meter once.
@12voltvids
7 жыл бұрын
Photon is crazy alright, but his videos are sure fun to watch.
@ZEROSTATIC72
7 жыл бұрын
Please check your use of the word oxidation. Thanks for the videos. :)
@12voltvids
7 жыл бұрын
ZEROSTATIC72 what's wrong with the word. in the presence of oxygen metals oxidize
@mialara2590
7 жыл бұрын
What ZEROSTATIC72 meant is that "oxidization" as you said is not a word, it's "oxidation".
@TechGorilla1987
7 жыл бұрын
A simple peck in to the garger clearly shows that "oxidization" is, in deed, recognized as a word meaning 'oxidation." That makes you and ZEROSTATIC72 are both wrong.
@coyote_den
7 жыл бұрын
bad contact means arcing, which means heat, which means rapid oxidation, right?
@mialara2590
7 жыл бұрын
I guess I was a little "idiotisized" there for a moment.
@lesstime1678
5 жыл бұрын
i love china things
@radioflyer9959
4 жыл бұрын
I love to throw China things in the dumpster 😂
@stuknda80z15
7 жыл бұрын
always thought sand paper was less aggressive than aluminum oxide. obviously if you think oxidization is a word you cant be taken seriously any way,should be called over flowing with garbage everywhere vids
@harrisleck3960
8 ай бұрын
Everyone can use a Variac to control the voltage your gear is getting. At my previous QTH in NorCal it was not uncommon to have over 126VAC. I would call the power company when that happened. I feed my large Variac into a Furman M-80X because the whole point for me is to reduce the line voltage to about 115VAC for my boat anchors. The Furman has a digital meter that matches the readings of my other VOMs. I wouldn't trust a cheap Chinese 'meter' like the one on the variac shown. YMMV. K9RJ
@12voltvids
8 ай бұрын
Everything on the bench goes through it, and the variac is isolated. I can go from 0 to 150 volts.
Пікірлер: 104