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    Variac's on sale right now at Circuit Specialists in AZ

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    j beede

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by j beede on Sat Dec 31, 2016 6:35 pm

    monkuboy wrote:Another question here... I plugged in the Variac and then plugged the ST-120 into the Variac.  When I turned on the ST-120, the voltage in the Variac dropped from 120.0V to 119.3V.  Isn't the voltage supposed to remain the same?   Same thing with trying the TV - there was a slight drop in voltage when turning it on, and an even slighter drop when just plugging in the TV without turning it on (it was in a ready state with the LED light on showing it was plugged in).  Shouldn't the Variac keep the voltage constant?

    A VariAC is a transformer with a mechanically variable secondary tap facility. It provides variable voltage via the big knob on top--it does not provide automatic, feedback-based voltage regulation. When you load the output of a transformer there will be an observable voltage drop versus the no-load voltage. Simply set the voltage to your desired level after applying the load. It sounds to me like you have a VariAC that is doing what it is supposed to do. Does it hum? Does it run cool? Those would be of greater interest to me.

    ...j
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    Peter W.

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by Peter W. on Sat Dec 31, 2016 11:01 pm

    OK..... A few things here. And from the perspective of one who has fiddled with the audio/radio hobby for now well over forty (40) years. So forgive me please if I ramble a bit on the pendantic side.

    a) A line conditioner is a good thing whether your AC line is typically contaminated or not. It maintains a steady output voltage within a very wide range of input voltages.
    b) It puts out a pure sine-wave at 60 hz (50 if in other zones). Not necessarily grid-tied (a few more $$ gets you that), but close enough that your on-board transformer will be happy.
    c) It is generally very quiet in normal operation, not so much if your incoming power is very nasty. Few here in the US will ever notice, in other words (unless the newly empowered Russians get their way - as demonstrated in Vermont lately. This is not political - look it up).
    d) It will protect your equipment against spikes, brown-outs and other artifacts far better than a mere surge protector. Or a V-A-T.

    So, if you have one, keep it!

    Now as to a Variable Auto-Transformers (!!ONLY!! General Radio and its heirs may call their devices "Variacs", please keep that in mind). They are mechanical devices that reduce/manage/increase incoming voltages by taking off a simple coil at varying points. And the output-to-input voltage variation *AND PROPORTION* is fixed by the position of the wiper on that coil. Loads can cause voltage sags if the incoming line is not of sufficient capacity to carry that load. If you are getting a small voltage drop, that is normal - VERY!~!~! small. 0.583 % is very, very small. Variable Auto-Transformers DO NOT have any voltage regulating capacity whatsoever.

    And, cutting to the chase, why it is that I would prefer an audio-grade line conditioner over a V-A-T 100% of the time. If your local voltage varies, a V-A-T is useless as the output is a fixed proportion to the input. Today, you are OK at 123 V-in, to 118 V-out. Tomorrow at 128 V in, not so much unless you are constantly (hour-to-hour) checking. Hence a set-and-ignore range of 85 - 145V becomes quite desirable.

    As to bucking transformers - they also have one singular virtue: They will _always_ drop the incoming voltage by a specific amount, and do not admit to adjustment on the fly. Still not as good as a line conditioner, but far, far better than a V-A-T.

    So, as John Muir once stated: Come to terms with your ass, for it bears you!. Understand what each tool is for, use it for that purpose, and let other tools provide as necessary for other functions.

    End mini-rant.
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    pedrocols

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by pedrocols on Sun Jan 01, 2017 2:05 am

    Peter W. wrote:OK..... A few things here. And from the perspective of one who has fiddled with the audio/radio hobby for now well over forty (40) years. So forgive me please if I ramble a bit on the pendantic side.

    a) A line conditioner is a good thing whether your AC line is typically contaminated or not. It maintains a steady output voltage within a very wide range of input voltages.
    b) It puts out a pure sine-wave at 60 hz (50 if in other zones). Not necessarily grid-tied (a few more $$ gets you that), but close enough that your on-board transformer will be happy.
    c) It is generally very quiet in normal operation, not so much if your incoming power is very nasty. Few here in the US will ever notice, in other words (unless the newly empowered Russians get their way - as demonstrated in Vermont lately. This is not political - look it up).
    d) It will protect your equipment against spikes,  brown-outs and other artifacts far better than a mere surge protector. Or a V-A-T.

    So, if you have one, keep it!

    Now as to a Variable Auto-Transformers (!!ONLY!! General Radio and its heirs may call their devices "Variacs", please keep that in mind). They are mechanical devices that reduce/manage/increase incoming voltages by taking off a simple coil at varying points. And the output-to-input voltage variation *AND PROPORTION* is fixed by the position of the wiper on that coil. Loads can cause voltage sags if the incoming line is not of sufficient capacity to carry that load. If you are getting a small voltage drop, that is normal - VERY!~!~! small. 0.583 % is very, very small.  Variable Auto-Transformers DO NOT  have any voltage regulating capacity whatsoever.

    And, cutting to the chase, why it is that I would prefer an audio-grade line conditioner over a V-A-T 100% of the time. If your local voltage varies, a V-A-T is useless as the output is a fixed proportion to the input. Today, you are OK at 123 V-in, to 118 V-out. Tomorrow at 128 V in, not so much unless you are constantly (hour-to-hour) checking. Hence a set-and-ignore range of 85 - 145V becomes quite desirable.

    As to bucking transformers - they also have one singular virtue: They will _always_  drop the incoming voltage by a specific amount, and do not admit to adjustment on the fly. Still not as good as a line conditioner, but far, far better than a V-A-T.

    So, as John Muir once stated: Come to terms with your ass, for it bears you!.  Understand what each tool is for, use it for that purpose, and let other tools provide as necessary for other functions.  

    End mini-rant.
    Several Amp manufacturers do not recommend the use of any line conditioners. Once again I am not an engineer so don't ask me why.
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    Blitzen

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by Blitzen on Sun Jan 01, 2017 7:11 am

    [/quote]
    Several Amp manufacturers do not recommend the use of any line conditioners.  Once again I am not an engineer so don't ask me why.[/quote]

    Can you remember which manufacturers are saying this? I'm curious as to why they might say this.
    I'm using a line conditioner on my home rig, and on virtually every piece of equipment in my work recording studio. There it is invaluable, because where I work a time signal is sent through once an hour to keep clocks in sync. The Tripp Lite filters that out!
    My take on Variacs: if you use one, you should also have installed a meter that tells you the AC power out level, otherwise it's rather pointless. Every time you turn the amp on, it should be referenced. Something such as a "Kill-A-Watt" is perfect for this, and cheap.

    monkuboy

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by monkuboy on Sun Jan 01, 2017 1:02 pm

    Thanks to those who replied to my questions. I think I'll be sending the Variac back as I was under the impression it kept the voltage constant rather than it being proportional to whatever the incoming voltage is. Also, I'm a bit concerned about quality since the dial is so poorly calibrated, having to turn it down to 105V in order to output 120V (at 120V on the dial it actually outputs 134V).
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    bluemeanies

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by bluemeanies on Sun Jan 01, 2017 2:49 pm

    Jumping in here a little late but I thought I would share.
    My line voltage in my house is from a low 115 to a high of 125.
    That is why I purchased a VARIAC. Heavy duty I bought one on eBay for $100.00. It came with a 22 amp fuse which I changed out to 10 amp fuse. I have a Kill a Watt that is connected to the Variac and the m125's connected to the Kill a Watt. At least now I have some control over the line voltage coming into my 2channel system.
    I also have a Furman Elite but found that the Elite was not enough. deepee recommended in a post a ground fault interruptor. I procrastinated and suffered a surge which burned out a transformer in my Grace Design m920. I was fortunate that the unit still had four years left on the warranty.
    I went to Home Depot and purchased two ground fault interruptors that have three outlets on each of them. They cost $26.00 each and have a manual reset.
    I have some equipment connected to the Furman and from the Furman to the ground fault interruptor. The rest of my equipment is connected directly into the ground fault interruptor and I fell a lot better than I did a few weeks ago.
    Every piece of equipment is protected but I am a realist...you cannot stop Mother Nature or control her, but I feel prepared for the worst.


    Last edited by bluemeanies on Mon Jul 31, 2017 8:25 am; edited 2 times in total
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    pedrocols

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by pedrocols on Sun Jan 01, 2017 3:31 pm

    Several Amp manufacturers do not recommend the use of any line conditioners.  Once again I am not an engineer so don't ask me why.[/quote]

    Can you remember which manufacturers are saying this? I'm curious as to why they might say this.
    I'm using a line conditioner on my home rig, and on virtually every piece of equipment in my work recording studio. There it is invaluable, because where I work a time signal is sent through once an hour to keep clocks in sync. The Tripp Lite filters that out!
    My take on Variacs: if you use one, you should also have installed a meter that tells you the AC power out level, otherwise it's rather pointless. Every time you turn the amp on, it should be referenced. Something such as a "Kill-A-Watt" is perfect for this, and cheap.[/quote]


    I do not precisely remember who. However, they argued that any amp with a properly design power supply should suffice. Thus the need or use for a power conditioner will be redundant.
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    bluemeanies

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by bluemeanies on Mon Jan 02, 2017 11:57 am

    pedrocols wrote:Several Amp manufacturers do not recommend the use of any line conditioners.  Once again I am not an engineer so don't ask me why.

    Can you remember which manufacturers are saying this? I'm curious as to why they might say this.
    I'm using a line conditioner on my home rig, and on virtually every piece of equipment in my work recording studio. There it is invaluable, because where I work a time signal is sent through once an hour to keep clocks in sync. The Tripp Lite filters that out!
    My take on Variacs: if you use one, you should also have installed a meter that tells you the AC power out level, otherwise it's rather pointless. Every time you turn the amp on, it should be referenced. Something such as a "Kill-A-Watt" is perfect for this, and cheap.[/quote]


    I do not precisely remember who. However, they argued that any amp with a properly design power supply should suffice. Thus the need or use for a power conditioner will be redundant.[/quote]



    I heard arguments on both sides but my 7700 is plugged directly into the wall outlet as recommended by the manufacturer. My m125's are connected to a Kill a Watt which is connected to a VARIAC.
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    10-E-C

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by 10-E-C on Fri Jan 06, 2017 10:13 pm

    I've been running two of these Chinese VARIACs for years, the 20 amp model runs my main system with the M125's, Holger's Janis and Aretha. The unit test good with a checker. Now the 5 amp runs my ST-70 system, it was wired incorrectly, so I transposed the hot and neutral wires. My house voltage runs in the high 123 VAC, so I set both VARICs to 118 VAC allowing for a little voltage drop under load when the amps are running. Every time I check my bias I also check my voltage out of the VARIAC and it is always spot on where I set it. 3 years running the 5A and 2 years running the 20A with no hint of a problem.

    TM

    eickmewg

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by eickmewg on Sat Jan 07, 2017 7:10 am

    So this is the third mentioned 5 amp model with reversed hot and neutral lines. Do we see a trend?

    monkuboy

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by monkuboy on Sat Jan 07, 2017 12:49 pm

    eickmewg wrote:So this is the third mentioned 5 amp model with reversed hot and neutral lines.  Do we see a trend?

    I tested the Variac I received the other day and it was wired correctly. That said, I ended up sending it back for a refund because for one thing, the dial calibration was so far off (measured 134.4V at 120V setting) and also, I was under the mistaken impression it regulated the voltage and kept it constant, whereas it doesn't keep it constant. I feel it was defective, though, because of the dial being incorrect.

    ramon68

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by ramon68 on Sat Jan 07, 2017 1:46 pm

    Monkuboy, did the voltage of the variac vary more than the incoming a/c? Or did it go up and down with the wall voltage?
    It wasn't designed to lock in a voltage, but simply to reduce the incoming voltage.

    monkuboy

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by monkuboy on Sat Jan 07, 2017 11:23 pm

    ramon68 wrote:Monkuboy, did the voltage of the variac vary more than the incoming a/c?  Or did it go up and down with the wall voltage?
    It wasn't designed to lock in a voltage, but simply to reduce the incoming voltage.

    It varied with the wall voltage, which now I know is normal but I was under the mistaken impression it kept the voltage constant at whatever the dial was set at.
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    Bob Latino
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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by Bob Latino on Sun Jan 08, 2017 9:35 am

    Two things that are true about these Chinese variacs ...

    A. Yes - The meters on these variac's are simple analog meters and are not particularly accurate. You always check the outgoing voltage on the variac's AC outlet with a multimeter.

    B. Once set .. the variac's outlet voltage will vary with your incoming line voltage. If your incoming line voltage goes up, the variac's output voltage will also go up. Usually at most locations, you will find a pattern. Lets say that you find over a period of a week that your wall outlet line voltage ranges from 121 to 124 VAC at any given time and your incoming line voltage today is 122 VAC. You should set your variac's output on that day to 118. If you do, then your variac's outlet voltage may vary from about 117 to 120 at any given time but will always top out at 120 VAC.

    Another thing to remember > Line voltage changes will cause bias setting changes. As your line voltage goes UP, your bias setting will also go up. Bias settings that "wander" are almost always related to line voltages that wander.

    Bob
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    Peter W.

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by Peter W. on Sun Jan 08, 2017 1:35 pm

    Bob Latino wrote:

    >>Snippage<<

    Another thing to remember > Line voltage changes will cause bias setting changes. As your line voltage goes UP, your bias setting will also go up. Bias settings that "wander" are almost always related to line voltages that wander.

    Bob[/b][/size]

    And why it is that I prefer to use an audio-grade line conditioner in situations of varying voltage. The output is fixed against a widely variable input, and the output is also a pure sine wave.

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    Bob Latino
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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by Bob Latino on Sun Jan 08, 2017 3:21 pm

    Peter W. wrote:

    And why it is that I prefer to use an audio-grade line conditioner in situations of varying voltage. The output is fixed against a widely variable input, and the output is also a pure sine wave.

    Consider though that many line conditioners do not offer "true RMS voltage regulation" .. They do filter and reduce noise on your incoming AC line and filter out AC power spikes but many do NOT regulate and/or adjust the AC voltage. They won't jack up a lower than 120 VAC and they will not bring down a higher than 120 VAC down to 120 VAC. Those that do offer true RMS voltage regulation tend to be expensive. Deepee's Furman 20i power conditioner is $3000+. I think Furman's smallest power conditioner that does offer true RMS voltage regulation is over $1000 in pricing. So .... Yes > some power conditioners are also VOLTAGE REGULATORS but in general only the very expensive power conditioners can regulate voltage ..

    Bob

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    slate1

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by slate1 on Fri Jul 28, 2017 10:51 am

    monkuboy wrote:
    eickmewg wrote:So this is the third mentioned 5 amp model with reversed hot and neutral lines.  Do we see a trend?

    I tested the Variac I received the other day and it was wired correctly. That said, I ended up sending it back for a refund because for one thing, the dial calibration was so far off (measured 134.4V at 120V setting) and also, I was under the mistaken impression it regulated the voltage and kept it constant, whereas it doesn't keep it constant.  I feel it was defective, though, because of the dial being incorrect.

    Full disclosure, I have the Circuit Specialist 5 amp version on order for use with my currently in production ST-120, so I am not speaking from direct experience here.

    I'm a little confused as to what the dial on top actually indicates? The meter on the front (which I understand is notoriously inaccurate), unless I'm mistaken, indicates the output voltage. Since the output voltage is relative to the line voltage I would not expect the top knob to be a "set and forget" setting and your findings aren't that surprising to me. In other words, I would assume that if I put the knob at 120V it's obviously not going to output a constant 120v because the output voltage is dependent upon what the variac is being fed from the line.

    So, the question is, what exactly is the use of the notations on the top dial then?
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    corndog71

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by corndog71 on Fri Jul 28, 2017 11:25 am

    slate1 wrote:
    monkuboy wrote:
    eickmewg wrote:So this is the third mentioned 5 amp model with reversed hot and neutral lines.  Do we see a trend?

    I tested the Variac I received the other day and it was wired correctly. That said, I ended up sending it back for a refund because for one thing, the dial calibration was so far off (measured 134.4V at 120V setting) and also, I was under the mistaken impression it regulated the voltage and kept it constant, whereas it doesn't keep it constant.  I feel it was defective, though, because of the dial being incorrect.

    Full disclosure, I have the Circuit Specialist 5 amp version on order for use with my currently in production ST-120, so I am not speaking from direct experience here.

    I'm a little confused as to what the dial on top actually indicates?  The meter on the front (which I understand is notoriously inaccurate), unless I'm mistaken, indicates the output voltage.  Since the output voltage is relative to the line voltage I would not expect the top knob to be a "set and forget" setting and your findings aren't that surprising to me.  In other words, I would assume that if I put the knob at 120V it's obviously not going to output a constant 120v because the output voltage is dependent upon what the variac is being fed from the line.

    So, the question is, what exactly is the use of the notations on the top dial then?

    Well, even if it isn't entirely accurate it still gives you a reference point. I don't even look at it. My Kill-a-watt shows me what my outgoing (from variac) voltage. It's made in China. Keep expectations low.
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    deepee99

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by deepee99 on Fri Jul 28, 2017 12:45 pm

    monkuboy wrote:Another question here... I plugged in the Variac and then plugged the ST-120 into the Variac.  When I turned on the ST-120, the voltage in the Variac dropped from 120.0V to 119.3V.  Isn't the voltage supposed to remain the same?   Same thing with trying the TV - there was a slight drop in voltage when turning it on, and an even slighter drop when just plugging in the TV without turning it on (it was in a ready state with the LED light on showing it was plugged in).  Shouldn't the Variac keep the voltage constant?

    A Variac's VAC output rides up and down with the input voltage. In other words, its output is not any more constant than your line voltage. They're great on the test bench when you're bringing a long dis-used amp back to life, because you can start with 70-80-volts to slowly goose the caps and tubes back into action as you bring them back to 117 VAC or so, but I would never rely on one to protect my system. If you get a line-voltage spike, the Variac's output will jump by the same volts. Plus, the volt-meters on the Chinese Variacs are notoriously inaccurate and indeed, they come assembled with built-in ground faults or polarity reversals. Only thing is, being basically just a transformer, they do put out sine-wave, which is good for tubes and s/s.
    Bite the bullet, get a studio-grade Furman. They have some solid-state internals but basically are just a great big multi-tapped autoformer and your gear will see a pure sine wave, clamped at 121 VAC regardless of line voltage. Plug it into a manual-reset GFCI and run all your gear off of it. Cheapest insurance on the planet.
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    Peter W.

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by Peter W. on Fri Jul 28, 2017 12:52 pm

    deepee99 wrote: >>SNIPPAGE<<
    Bite the bullet, get a studio-grade Furman. They have some solid-state internals but basically are just a great big multi-tapped autoformer and your gear will see a pure sine wave, clamped at 121 VAC regardless of line voltage. Plug it into a manual-reset GFCI and run all your gear off of it. Cheapest insurance on the planet.

    Yep.
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    slate1

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by slate1 on Fri Jul 28, 2017 1:17 pm

    Peter W. wrote:
    deepee99 wrote:  >>SNIPPAGE<<
    Bite the bullet, get a studio-grade Furman. They have some solid-state internals but basically are just a great big multi-tapped autoformer and your gear will see a pure sine wave, clamped at 121 VAC regardless of line voltage. Plug it into a manual-reset GFCI and run all your gear off of it. Cheapest insurance on the planet.

    Yep.

    Just to be clear - the Furman units, like the P1800 regulate to approximately 120v +/-5v as long as the input voltage is between 100-140v - it's not until you get to the $3,000+ units that you get +/-1v regulation.  The APC H15 Conditioner (which I own and has been very reliable) provides close to the same level of regulation as the P1800 (120v +/- 5% between 102-132v) at a fraction of the cost.  Neither of the devices, however, will keep me consistently under the 123v I'm trying to achieve with the APC providing potentially up to 127v.

    I understand and appreciate the lack of surge protection, but in the end though, the variac seems like it would be a better choice for accurate voltage regulation, although requiring more "maintenance" - I'm wondering if I shouldn't just plug a kill-a-watt P4400 meter into the variac to get a better quality reading than the analog sweep meter?  (you'll have to google it - won't let me post a link because I haven't been a member for 7 days)

    Simply set the variac to 117v before powering up the amp and I believe  I'm set.  Also wondering if I should just plug the variac into the APC H15, providing surge protection, or just straight into the wall which, granted, would leave me exposed to spikes.
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    deepee99

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by deepee99 on Fri Jul 28, 2017 1:39 pm

    slate1 wrote:
    Peter W. wrote:
    deepee99 wrote:  >>SNIPPAGE<<
    Bite the bullet, get a studio-grade Furman. They have some solid-state internals but basically are just a great big multi-tapped autoformer and your gear will see a pure sine wave, clamped at 121 VAC regardless of line voltage. Plug it into a manual-reset GFCI and run all your gear off of it. Cheapest insurance on the planet.

    Yep.

    Just to be clear - the Furman units, like the P1800 regulate to approximately 120v +/-5v as long as the input voltage is between 100-140v.  The APC H15 Conditioner (which I own and has been very reliable) provides close to the same level of regulation (120v +/- 5% between 102-132v) at a fraction of the cost.  Neither of the devices, however, will keep me consistently under the 123v I'm trying to achieve with the APC providing potentially up to 127v.

    I understand and appreciate the lack of surge protection, but in the end though, the variac seems like it would be a better choice for accurate voltage regulation, although requiring more "maintenance" - I'm wondering if I shouldn't just plug a kill-a-watt P4400 meter into the variac to get a better quality reading than the analog sweep meter?  (you'll have to google it - won't let me post a link because I haven't been a member for 7 days)

    Simply set the variac to 117v before powering up the amp and I believe  I'm set.  Also wondering if I should just plug the variac into the APC H15, providing surge protection, or just straight into the wall which, granted, would leave me exposed to spikes.

    The cheaper Furmans, like the 1800 models, do indeed have a 5-volt slop factor, which is still pretty good. I use an 1800 in the den to protect a combination of tube pre-amp and s/s amp.  Furman's studio grades, such as the SPR-20i I use in my all-tube main system have a 1-volt variation (off 121) within the input voltage range you mentioned. Believe me, I spent hours with their English-as-first-language-speaking tekkies before dropping 2 large on it. All I can say again, the sumbitch does its job.
    If you're going to drop $30 on a kill-a-watt, why not add another $70 and get a Fluke, which will give you far greater accuracy and utility. And again, you can "set" your Variac to 117 VAC (based on 120 VAC line voltage at the time) if your line voltage has a momentary spike to 130, the Variac will be right behind it at 127 VAC.
    And to preach to the choir, if you don't have a manual-reset GFCI plugged into your wall outlet, nothing will save you from spikes, up or down.
    BTW, Welcome to the board. I'm one of the noisier ones here, so take whatever I say with a grain of salt.
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    bluemeanies

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    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by bluemeanies on Sat Jul 29, 2017 9:47 am

    I have a STACO VARIAC. I must admit it is a bit of overkill for my system but I was able to purchase it for $100.00 on e-bay. They were asking $150.00. It IS INDUSTRIAL STRENGTH. It came with a 22amp fuse. I connected a Kil-O-Watt to the the Variac and my m125's to the kil-O -watt.
    My house readings with my Fluke read from the low of 117 to highs of 125.
    Not good for tube life.
    I kept blowing a circuit. I thought the breaker could be bad but after talking to a tech the 22amp fuse I found was to much and dangerous for the house. Thankfully the breaker was doing its job. I replaced the22amp fuse with a 10 amp and that solved the problem.
    Now each time I turn on the tubes I regulate the Variac to 119.8 or there abouts and I also introduced a couple of ground fault line interruptors (manual)
    Have not had any issues in over a year.
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    Tubes4ever

    Posts : 107
    Join date : 2015-07-14
    Location : Star, Idaho

    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by Tubes4ever on Sat Jul 29, 2017 1:40 pm

    Speaking of Kill O Watts, I noticed that mine shows the voltage as almost 2 volts below what I measure with both of my Fluke Meters. I was wondering what others who own a Kill O Watt have observed as far as voltage accuracy? I realize that 2 volts isn't that big of a deal, but with a display that shows tenths of a volt, I would expect better accuracy.
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    deepee99

    Posts : 1759
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Variac's on sale right now at Circuit Specialists in AZ

    Post by deepee99 on Sat Jul 29, 2017 1:47 pm

    Tubes4ever wrote:Speaking of Kill O Watts, I noticed that mine shows the voltage as almost 2 volts below what I measure with both of my Fluke Meters.  I was wondering what others who own a Kill O Watt have observed as far as voltage accuracy?  I realize that 2 volts isn't that big of a deal, but with a display that shows tenths of a volt, I would expect better accuracy.
    Fluke is the gold standard of all electrical measuring. I actually knew old John and his culture of perfection prevails, according to the people who've worked for him since. Miserable perfectionist and not a particularly congenial guy, but let me give you an analogy. If you're in Switzerland and your train is a minute or two late or early, there's something wrong with your watch.

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    Re: Variac's on sale right now at Circuit Specialists in AZ

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