Equi=Tech 'Q' tranny based DIY balanced power project

[ThomasW]

Glen's DIY project piqued my curiosity about the 'blem' transformers-in-a-box offered by Equi=Tech. So I ordered a few.... :wink:

My oh my, these are indeed the holy grail of transformers ... 8O 8O 8O 8O 8O 8O

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This is the 1.5kVA unit. Now it may not appear all that large until it's compared to the 'higher capacity' 2.0kVA unit from Plitron.

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Approx 70lbs for the Equi=tech and 35lbs for the Plitron. Price difference about +$70.00US delivered more for the Equi=Tech product.

There are a couple more comparison pictures:

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Since I'm in the process of moving all my power amps to the basement, each Equi=Tech unit will be hardwired with a single outlet. Then remotely triggered using a sequencer from Furman.

If anyone has an interest in these Equi=Tech transformers buy now! They sold out of the 2.0kVA units, and there aren't very many 1.5kVA units left. And once they're gone that's it ...... :E

BTW, these are the transformers used in their $$$$$ Model Q1.5 devices.

[Saurav]

It's good to see pictures. I wish my stereo fund wasn't at $0 right now I'd thought about picking one of these up months ago, but I wasn't too clear about what the final thing would look like, what parts I would need to add to it, and so on.

So this has nothing wired up, correct? You'll need to add outlets, fuse, and any soft start and/or filtering circuitry?

A sequencer would be good too... I might be able to get my wife to use the stereo if I could give her a "hit this switch and everything will turn on". User-friendliness hasn't been a design goal for me so far

[ThomasW]

What you see is what you get, a transformer mounted in a utility box. They claim that the design is inherently soft-starting, we'll see... since the Piltron's certainly aren't.

Glen mounted his in a fancy Par-Metal chassis, then, added all sorts of goodies.

My plan is to do a cutout for a one hospital grade duplex outlet per transformer and hardwire the AC in. Probably won't bother with any filtration since that's included in the Furman.

[jdybnis]

My oh my, these are indeed the holy grail of transformers ... 8O 8O 8O 8O 8O 8O

This is the 1.5kVA unit. Now it may not appear all that large until it's compared to the 'higher capacity' 2.0kVA unit from Plitron.

Approx 70lbs for the Equi=tech and 35lbs for the Plitron. Price difference about +$70.00US delivered more for the Equi=Tech product.

I don't know squat about transformers. I know the equi=tech devices have a real good reputation, but bigger isn't always better. You put 'higher capacity' in quotes. Is the equi=tech underrated at 1.5kVA? All else being equal, more power in a smaller package makes my back happy.

[JonMarsh]

Transformer ratings are like anything else; you have to check the rating conditions. Usually, it's based on percentage of regulation no load to full load, and maximum allowable core temperature rise. This is specced normally under conditions that aren't often encountered in the real world- such as true sine wave power draw, and something close to unity gain power factor.

In the real world, with conventional power amps, which only draw at the top of the AC waveform, and power lines with offset voltage between one phase and neutral, the stress on the transformer can be higher than expected, and come from sources other than conventional power transfer. A larger transformer like the Equitech, all things being equal (similar core steel material), will have a greater energy storage and saturation level than a smaller transformer- it can handle more abusive conditions. Now, that may not be always necessary, but it's a measure of "over building" to meet the outer envelope of the requirements, and the true spirit of the spec, not just the letter, which is too often missing in this day and age of $50 DVD players and paring costs and performance to the minimum, in order to make a buck.

With 50/60 Hz transformers, toroidal or not, you get what you pay for, and copper and iron cost money...

Just my 0.02.

[ThomasW]

Stuff is stuff as they say, and with regard to transformers bigger certainly is better. The reason for this is that they are limited by heating. So it takes a lot longer to heat up 70lbs compared to 35lbs.

There is the text from a paper included with each Equi=Tech transformer, it says.........

This 2.0kVA (20 amp) transformer was designed to be derated for use as a 1.5kVA (15 amp) transformer where only about 12.5 amps continuous duty are necessary, and for use where 14 gauge wire with a single 15 amp 2 pole feeder breaker may already be in place. However, it can be used at it's full rating of 16.7 amps continuous, but after about 4-6hrs at full load it may begin to run at temperatures above it's rating of 44 degrees C. This is why it's recommended for use as and is sold as only a 15 amp tramsformer. If using at 20 amps, be sure to use proper circuitry

No such information was provided with the 2.0kVA (20 amp) unit from Plitron. I plan on checking their website to see what their specs say.

I find it hard to imagine that normal HT situation where anyone would be needing 16.7 amps continuous for 4-6hrs, given the transient nature of audio signals.

I bought these to be hardwired in the basement, not to be used as portable units. So dragging them once from the front porch to the basement, was my only task.

Besides I can't wimp out now since they were hand carried from the FedEX truck to my porch by a little blonde woman about 5'6". She declined my offer of assistance, and said it was too much hassle to use her handtruck .. :wink:

[Saurav]

Man, 70 lbs. I hadn't stopped to think about that. What are the physical dimensions of teh transformer/box? It's hard to get an idea of that from the photos, especially since I have no idea how big the Plitron transformer is.

For my specific system, I feel like I could get by with a much smaller transformer. My SS amp puts out ~ 25WPC, so it probably doesn't draw more than 100W from the wall? My tube amp puts out ~ 3.5WPC, and I know it draws about 60W or so (how's that for efficiency ). There's a 100W plate amp for the sub. All the rest are 'small things' - CD player, turntabe motor, phono stage, active XO. So something like 500VA should take care of my entire system, I would think.

[ThomasW]

The box is 21" long X 14" wide X 4" high. The Equi=Tech transformer is ~12" diameter

It's not the output of power of the amps that's important. It's the max amount of current they can draw from the wall. Multiply the amp's current draw times the voltage to determine it's VA draw. Sometimes a units max current draw is listed on the label. It's important to have some headroom.

VA = voltage (120) times amperage draw. For example, if a power amp has a max draw of 6 amps, then the VA needed is 720 just for that single device.

I wouldn't use any power amps with a small transformer that's why I'm buying all these BIG transformers.

The small 800VA transformers from PE are fine for a TV, preamp, DVD/CDP, etc, etc where the power draw is fixed. Power amps and receivers are a dynamic load, so one needs to be careful sizing them to a transformer.

[Saurav]

Power amps and receivers are a dynamic load, so one needs to be careful sizing them to a transformer.

Understood, but I'm running much lower powered amps than most people. I should have added that as a cautionary note in my post, I guess. You make a very good point about peak current draw vs. average power consumption for an amp.

[goskers]

I just ordered one of these beasts today. Close to 80lbs is the shipping weight :E

From what I have read and the knowledge gained from the poobahs here, balanced power is a great way to go.

goskers

[ThomasW]

Good going!

Wait until you see the shipping box ..... 8O

[goskers]

To finish one of these properly should I just follow the cheapskate or is there a different method that should be used in this instance?

thanks

[ThomasW]

How do you want to use it?

[goskers]

I would like to use it to power up to 4 devices. A class d amp, DEQX PDC2.6 and a transport. Aside from that, I would like to do it right the first time around. If there is anything that would make a major difference then I might as well throw it in there.

Thanks

[ThomasW]

It's technically stout enough to provide up to 20 amps of intermittent current if the wiring is thick enough. That means you could hardwire it into a dedicated circuit and plug a TON of gear into it.

You could chop up the box and put some receptacles and filters inside it. But the box is so heavy that it's really designed to be hardwired on a dedicated circuit.

For one of mine, the plan is as follows. Install a single Hospital grade outlet in the chassis. Then plug in one of these...FURMAN PM-PRO II SMP CONDITIONER/MONITOR 20A

[goskers]

Is there any reason that the 15A model of the Furman gear would not work well for someone on a budget? I can justify the 150$ or so but another 300$ just isn't in the plans. All the features except for the 1.5+/- accuracy, which would be 2+-, and a fancy digital display which would become dimmable LED's.


Thanks

[Glen B]

What you see is what you get, a transformer mounted in a utility box. They claim that the design is inherently soft-starting, we'll see... since the Piltron's certainly aren't.

The Equi=Tech Q transformer design is indeed soft starting. :T The no-load inrush current of the 2kVA model measured with my Fluke meter was 2.4 amps.

[ThomasW]

The lower cost unit will be fine. Just don't hook up several big class A monoblocks to it, or you'll pop the internal breaker ... :wink:

[goskers]

Have not received my transformer yet but did get my Furman Series II Plus D. Thankfully, PE was offering free shipping!!

The big boy should arrive anyday now.

goskers

[ThomasW]

I found Equi=Tech to be slow processing and shipping orders. And I didn't receive any tracking info unless I harrassed them on the phone.

My Furman PS-Pro Series II sequencer arrived today, now I need to build a remote trigger to use it...

[goskers]

Well, I arrived home from work today to find a large white box on the front porch. When I tried to move it with my foot I realized that I would have to get the back brace to move this beast.

The trannie and the box seem to be of very high quality. Pictures just didn't do justice to how big this thing really is. I can't wait to get it hooked up with the Furman conditioner.

goskers

[Eric S]

Hi Guys,

Just got off the phone with Joe from Equi=Tech - my 1.5kVA transformer in a box should arrive by the end of the week. I'm planning on using it to run various parts of my system (don't think its enough to power the entire system) in the near future.

Anyhow, I have a question about wiring it to the house AC mains. The wiring diagram shows that the center tap of the 60-0-60 should be connected to service ground, much like the diagram below. Wouldn't this re-introduce harmful currents that may be lurking in the ground (and that balanced power is supposed to remove)?

Would it be better to place a diode (use a 600v 35A diode bridge) between the center tap and the service ground? This way, if necessary, current would flow from the equipment to ground, but not from the ground into the equipment...

Any thoughts?
Thanks!
Eric

[Glen B]

There is no current flow at the center tap (hence the (60V-0-60V) and therefore no harmful currents to be introduced/reintroduced. Connect the center tap and shields directly to ground. Grounding also helps to stabilize the output of the secondary.

[Eric S]

Thanks, Glen!

Looking at the information posted in the various balanced power threads here, it looks like a good margin of safety and headroom would limit the power demands plugged into this 1.5kVA transformer to about 700-800VA. Is this correct?

If so, I think I'll use it to power my amps for L-C-R channels (Marantz MA500s - 125 watts each), RPTV (275 watts), preamp, and all of my source components (~150 watts total). I'll power the surround channel amps and sub amp separately. Is this a reasonable load for a transformer of this size?

Thanks!

[Glen B]

Thanks, Glen!

Looking at the information posted in the various balanced power threads here, it looks like a good margin of safety and headroom would limit the power demands plugged into this 1.5kVA transformer to about 700-800VA. Is this correct?

If so, I think I'll use it to power my amps for L-C-R channels (Marantz MA500s - 125 watts each), RPTV (275 watts), preamp, and all of my source components (~150 watts total). I'll power the surround channel amps and sub amp separately. Is this a reasonable load for a transformer of this size?

Thanks!

I would go to as much as 1,000VA and not give it a second thought. Total up the maximum power consumption of the components you will be using with the transformer, not their rated output power (in the case of amplifiers). I have been powering my 300 watt-per-channel amp (1.5kW max. power consumption) from the 2kVA Equi=Tech transformer without problem.

[ThomasW]

Is this a reasonable load for a transformer of this size?

Eric, I think you can plug all your amps (including surround and sub) into one transformer if you want......

In the real world these are 2kVA transformers. Equi=Tech just derates them for use with 14 gauge wire. They can easily supply supply 20 amps intermittently up to the point where the transformer itself heats up. (Heating the core is the limiting factor for all these transformers. And according to Equi=Tech they can run 4-6 hrs at max load before reaching the thermal limits of the core). I doubt that there are many situations with audio/HT where 20 amps is being pulled continuously for hours on end. (We're not talking Arc welding here folks ...:wink: )

I plan on plugging in a Aragon 8008BB, a Ayre V-5 and a Adcom 555 all into a single transformer and don't anticipate any problems at all. These 3 amps were previously run by a single BPT device before I bought the Equi=Tech.

[Eric S]

Thanks Glen & Thomas! It would be great to run the entire system through the one transformer - I didn't really want to have to buy another one! My surround amps are MA500s as well and the sub amp is an Adcom GFA545ii. Since its all class B amplification, the draw is not continuous (and with 2 small kids in the house, the system rarely runs at refernce levels).

Would there be any problem with plugging my Panamax 1000+ power filter into the transformer and then plugging the transformer into the wall outlet? (It seems fairly similar to your intended power filter, Thomas) It would be pretty easy to just add a plug on one end of the transformer and an outlet on the other end...

Thanks!

[ThomasW]

Yeap just don't exceed the rating of the Panamax, get a second Panamax or wire in another outlet.

I wall mounted and hardwired one tranny this morning, and have the Furman plugged into it.

Now I need to create a low voltage trigger to cycle the Furman. My old hand-me-down audio gear is used it the family room, and none of it has triggering circuits.

I bought a low-buck variable output DC power supply from PE. Now I just need to run a switch that cycles the DC on and off, to trigger the Furman Sequencer...... :wink:

[Glen B]

What you see is what you get, a transformer mounted in a utility box. They claim that the design is inherently soft-starting, we'll see... since the Piltron's certainly aren't.

Glen mounted his in a fancy Par-Metal chassis, then, added all sorts of goodies.

I removed a couple of the "goodies" -- the GFCIs -- and made a new rear panel. I found my system to have greater transparency and better bass definition without the GFCIs in the circuit. Inside the GFCIs, current from the line terminals passes through ordinary, thin PCB traces and two sets of switching contact points per pole on to the load terminals. That's a total of four contact points per 60-volt leg. All of the available GFCI brands have this same basic construction. I tried obtaining alternative earth leakage circuit breakers which are suitable for mounting in the chassis but those were very difficult to get.

before and after pics/GFCI internal pics:

[cdwitmer]

Toroidal transformers suitable for balanced power are much more readily available in the USA than where I live (Tokyo). In Tokyo, the power is 100V/50Hz. Depending on which country you take as your reference, this is either a 20% difference or a 16.67% difference, but in either case, both the voltage and the frequency differ by exactly the same percentage.

My question is: since there is an identical percentage difference between BOTH the voltage and the frequency of commercial mains power in the USA and Tokyo, shouldn't it be possible to take a balanced power unit designed for the USA market and use it in Tokyo without any modification? My belief (perhaps naive) is that the only difference would be the kVA rating of the unit.

Specifically,

American voltage (120V) and frequency (60Hz) versus
Tokyo voltage (100V) and frequency (50Hz).

I know from experience that if you take an electrical generator designed for the American market, you can use it in Tokyo simply by decreasing the rotation speed of the rotor by 16.67%. Ditto for an electrical generator designed for use in Tokyo: you could use it in the USA simply by increasing the rotation speed of the rotor by 20%.

Since the toroidal transformers used in balanced power units are basically passive components, why wouldn't a model designed to split 120V/60Hz power also split 100V/50Hz power just as well, seeing as the *relationship* between voltage and frequency is constant in both cases?

Thanks for putting up with my "newbie" questions!

Christopher Witmer
Tokyo

[Dennis H]

Christopher, I think you're making it too hard. This isn't like a generator. The 120V unit should work fine because your 100 volts doesn't exceed its rated capacity. Frequency in = frequency out, 50Hz or 60Hz or whatever. Voltage in = voltage out except the output is +V/2, -V/2 instead of +V, 0.

[cdwitmer]

Thanks, Dennis. That was what I thought too, but I made the mistake of asking the tech support staff of two different manufacturers. One replied that I could use the USA models in Tokyo "as is," (except that the kVA rating would change a bit). The other told me I could not, and I would have to get a model designed for Tokyo's power. So then I figured, "When all else fails, ask at the HTGuide Forum!"

[cdwitmer]

Hmm, I think I may now be getting closer to the reason why two different tech support departments each gave me different answers. Avel-Lindberg's website says that a toroidal transformer designed for use at 50Hz will also work at 60Hz, but not vice-versa. (The lower-frequency transformer will be slightly larger.) Avel-Lindberg rates their Y23 series trannies as 50/60Hz units, but the other company I contacted distinguishes between 50Hz and 60Hz models in the product list.

[cdwitmer]

Balanced power: okay to connect two toroids?

In building a balanced power system, I'm thinking of taking two Avel 1000VA toroids with 30+30V outputs and connecting them: the primary side inputs connected in parallel and the secondary side outputs in series. I'm hoping that would give me the functional equivalent of a 2000VA toroidal transformer. I'm aware that if either of the two toroids fails, the whole system will cease to function, but that seems like a risk I can live with. What I want to know is, from the perspective of performance as a balanced power system, is this a "bad idea"? The efficiency whereby phase-differential components are cancelled out depends on the precision of the matching between the two halves of the transformer's windings, but I can't see how connecting two transformers together would make any difference in this regard. However, if I'm overlooking anything important, somebody please point it out to me! THANKS!

[cdwitmer]

Sorry, let me rephrase that last question; if I want to double current handling I need to be connecting two identical transformers entirely in PARALLEL . . . at least, that's the idea in a perfect world. What I want to know is, in real-life application, would it be okay to connect a pair of 1000VA toroids in parallel to handle 2000VA in a balanced power system? Thanks!

[ThomasW]

I want to know is, in real-life application, would it be okay to connect a pair of 1000VA toroids in parallel to handle 2000VA in a balanced power system?

I'm not certain but I don't think that's going to do what you want. I think that still means there are still 2 small transformers not a single big one, given that the output of the trannys is limited by the heating of the core/cores.

I suggest saving up for either the DIY Plitron or the Equi=Tech "Q" in a box. Although more $pendy than a pair of smaller tranny's, these are literally a 'once-in-a-lifetime' investments, well worth saving up for...

[ThomasW]

I just ask Jon and he said it's a no go...He listed a bunch of reasons that were beyond my technical understanding.

[cdwitmer]

Many thanks to both of you! At least now I can stop barking up the wrong tree.

[cdwitmer]

Are these Bryston 4B trannies particularly appealing?

In my search for a balanced power solution, I came upon some surplus Bryston 4B trannies (500VA) that could probably be used to make balanced power systems, although I have concluded that their relatively low efficiency (91%) and relatively high price compared with Avel-Lindberg ($65) makes them less than ideal. But maybe someone more knowledgeable would be a better judge of these than I am. I'd be grateful if someone would check out the linked image and give me their opinion.



My understanding is that Bryston 4B amps used a pair of these trannies, so I suspect there was some sort of power balancing going on inside the amplifier itself. I suppose that in a transformer, conversion efficiency isn't everything; perhaps these trannies have some properties that make them especially appealing? My feeling is that it makes more sense to spend an extra $4 for the Avel-Lindberg 800VA units, or special order the 1000VA units.

[ThomasW]

For the difference in price I think the 800Va are the way to go. A primary issue is that after buying several of these you reach the price of the Plitron, and don't have the ability to power big/hungery receivers or amps.

[DIY_newbie]

Is there any particular reason why people don't use 4 of the avel torioids (8VA ~6.6Amps) each to drive a single outlet with its own filter?? I was thinking that would be the best possible isolation between the digital components and power amps???

I'm really intrigued by buildig a balanced power box for my equipment. I recently started on my first DIY speaker project using Fountek Ribbons and PR170s. I noticed that when I power up my system I have alot of "hum". I think its probably the much higher sensativities of my new speakers ~96db vs 88db for my old speakers making the noise much more audible..

From what I've read on this thread a balanced power system would reduce this hum? I still don't understand exactly how this is going to help. If the interference has already been picked up on the Hot AC before the outlet, how does converting to balanced power correct this problem? I can see how running balanced power to my components will remove the noise picked up from the wall to the component in the same way that balanced signal cables eliminate common noise picked up between the source and destination. Is the argument that most of the noise will be picked up between the wall and the components themselves? I would think that the extremly long distance between the powerplant and my home would pickup alot more interference than the short cable between my wall and the amplifiers? Do you add low pass filters to the AC line? do you shunt the high frequency noise to ground for both + and - in a blanced powersupply?

Should I have started a new thread of my own? If so, would a moderator please split this topic for me

Thanks inadvance,

--Chris

[ThomasW]

I could split the thread, but why don't you take a look at these threads then start your own.

https://www.htguide.com/forum/showthread.php?t=8227

https://www.htguide.com/forum/showthread.php?t=9373

https://www.htguide.com/forum/showthread.php?t=3584

[cdwitmer]

I received a very interesting reply from Avel-Lindberg tech support. I had clearly explained my intention to use one or more of their toroidal transformers in a balanced AC power system, and asked them if multiple Y23 transformers could be connected together to increase the current rating of the system. Their tech support replied that many Avel-Lindberg customers use two, three, or even four units connected in series or parallel and it is not a problem. So the kVA rating could be doubled, tripled, or even quadrupled over the case where a single Y23 transformer is used . . . or so they claim. As a novice I am reluctant to second-guess Jon in such matters, but I wonder why the Avel-Lindberg tech support gave came up with a different answer . . . one caveat, however: I did not explain to them that the balanced AC power system would be used with hi-fi audio . . .

[ThomasW]

When I ask Jon initially he started talking about using multiple transformers for various audio project power supplies. When I specifically mentioned balanced power then he said no.

Jon has seen one of my "Q" transformers and has said yes you could use one of those for 100V/50Hz were it derated for heat.

The other option is to do what everyone did before the existance of the 'net'. Buy the parts, build your idea and plug it in. If it blows up, then you know it wasn't supposed to be used that way .... :wink:

[cdwitmer]

LOL

I took that approach in a previous life as an amateur fireworks manufacturer . . . and I still have most of my appendages. But I think I'll not push my luck too far . . .