[bjski]

Any help would be appreciated seeing that I'm not EE. I purchased a Torus RM 2.5 for use with source components in my home theater. I plugged an Onkyo 5508 preamp and a Sony TV into it. After about 20 minutes the unit shut down. I reset the unit and tried just the TV or the Onkyo plugged into the Torus with another 2 shutdowns. I waited and let the Torus rest another 24 hours. I plugged just the Onkyo into the Torus with the Torus up on block's. In about 2 hours another shut down. The Torus was extremely hot and I assume a thermal shut down. I wouldn't think the Onkyo or TV would draw to much current to cause the unit to shut down. Any thought's seeing how I have another day before I can complain.

I do have Bryston Bit-20 [Torus] for my 2 channel system and it doesn't even get warm.
Thanks,BJ

[Folsom]

Onkyo 5508 = 1.2a

It can handle 2.5a, the Torus

What is the TV rated at?

It should NOT be heating up. However if it ran at too high amperage it may have melted some insulation and it sounds like it has either thermal or current protection that is being activated.

A short in it somewhere could be the problem. I'd check the TV ampere rating (probably written on the back, or if it has watts for the whole unit divide by 120, like 600/120=a) and see if you were exceeding anything.

It might just be a bad transformer.

[bjski]

Thanks for getting back to me. The TV is rated a 300 watts so both units combined can be causing it to shut down. What I find interesting is when I just use the Onkyo by itself the unit still shuts down in about 2 hours. The same happens when it's just the TV and by the formula that demands more than 2 amps. I'm thinking that something is wrong however originally I was using more than 2.5 amps.

[Folsom]

Without knowing all the parts inside...

I'd be afraid that it's simply faulty. I can't tell you if it's before or after using both, however.

Again, the small wires inside the transformer can, with heat, lose insulation and begin to touch and cause a short; or excessive current draw anyway.

It'd be nice to see how much current it's drawing with nothing plugged into it, because then we'd know if something in the transformer is likely faulty.

What happens if you plug it in without anything, does it heat up? That would also tell us there is something faulty within it, since it shouldn't be doing anything at all without a load.

I assume if the heat is noticeable, then it's a pattern that is somewhat large as opposed to heat from a small piece of it. The only large thing in it, would be the transformer.

[bjski]

The unit does not heat up with no load on it. Turned it on and let it operate with no load. I'm guessing the load from the Onkyo is a little much for the Torus.

[drummermitchell]

Didn't you say on the bryston page that the box that it came in was destroyed.
Sounds like it was tossed around pretty good to have the box destroyed.
Could only imagine what's going on inside the Torus.

[Folsom]

Unless it generates a lot of DC, something is wrong. It's possible it isn't the Torus.

Try the TV alone. If it doesn't cause heat in the Torus, then the reciever has a problem. The TV is right at the rating for the Torus, but it shouldn't cause heat. I am sure the Torus has minor room for difference.

At least we know the Torus isn't shorted. But it may still have problems. Feel free to post pictures of inside if it doesn't void warrenty.

[One and a half]

The RM2.5 is a transformer after all, so the rating of 2.5A x 120V = 300VA. Note the VA, not watts. To equate watts the formal is V x I x pf (power factor).

If your load was only a 300W filament lamp, the transformer would run quite happily all day. The power factor of the load in that case is 1. TVs and amplifiers always draw a non sinusoidal current, at a power factor that's less than 1, the numbers can vary, but based on past experiences, a number of 0.6 of power factor is a safe margin to allow for derating (this figure used for inverter outputs driving rectifier loads, SMPS etc.). The source, in our case the Torus, must provide for these losses, it doesn't have much of a choice.

If we apply that into our formula, the available VA is still 300VA, but the pf is now 0.6 not 1 anymore. So our torus 300VA transformer is now only capable of 0.6 x 300VA = 180VA or 180/120V = 1.5A.

The TV's figure of 300W at 120V = 2.5A at pf of 1. We are already overloading the Torus.

The Torus is working fine, and protecting itself against excessive loads. That's why it's getting hot and shutting down. If you can't return the Torus, nothing's lost, you can use the Torus for source components, e.g. computer, BD player, Tuners without a problem. For amplifiers and TV the story is very different.

Add up all the Watts and VA numbers from the nameplates and divide by 0.6. This will give you the figure in VA. Divide by 120V and select the nearest higher value Torus. Add any more if you plan to upgrades.

TV 300W
Amplifier 600W (guessing)

Total 900W / 0.6 = 1500VA / 120V = 12.5A that would be a Torus RM15. Big jump in price.

Improving the power factor to be 1 is a lot more complex to engineer out, when it comes to non linear loads. It is far more desirable to select a higher power device instead and cop the losses.

[One and a half]

The BIT20 can deliver 20A of current. it is therefore quite capable of a reasonably powerful amplifier system.

[Folsom]

OAAH, what makes you assume they didn't figure the Torus rating that way to begin with?

Also the receiver on it's own won't exceed the limitations with your power factor correction, yet the Torus will overheat.

[bjski]

The BIT20 can deliver 20A of current. it is therefore quite capable of a reasonably powerful amplifier system.

I have 2 Bryston 7BSSST/2,Bryston BHA-1, BDC-1, BDA-2 and a Bat 32 SE plugged into the Bryston Bit-20 no problems. The Bit never gets warm.

 

[bjski]

Unless it generates a lot of DC, something is wrong. It's possible it isn't the Torus.

Try the TV alone. If it doesn't cause heat in the Torus, then the reciever has a problem. The TV is right at the rating for the Torus, but it shouldn't cause heat. I am sure the Torus has minor room for difference.

At least we know the Torus isn't shorted. But it may still have problems. Feel free to post pictures of inside if it doesn't void warrenty.
[/quote

Torus sent me some interesting information on TV's today. We seem to sort everything out for the moment so I'll see how it goes.

Thanks for your help.

[bjski]

Difference between True Power and Volt-Amp (VA)
By Brutech
Torus sent me a word document.

[bjski]

The Torus is working fine, and protecting itself against excessive loads. That's why it's getting hot and shutting down. If you can't return the Torus, nothing's lost, you can use the Torus for source components, e.g. computer, BD player, Tuners without a problem. For amplifiers and TV the story is very different.

One and half,
I'm using the Torus 2.5 as you suggested as just a source power conditioner. So far all is well. I guess why I was upset was the store I purchased from advertised it for source components or TV use. I do believe all is well now and thanks for your help. The Bit-20 is an amazing product.

[One and a half]

I'm using the Torus 2.5 as you suggested as just a source power conditioner. So far all is well. I guess why I was upset was the store I purchased from advertised it for source components or TV use. I do believe all is well now and thanks for your help. The Bit-20 is an amazing product.

That's good news and a great result for the RM 2.5.

The BIT-20 is a little thin on information from the manual to download, but I see it is a Plitron based device. Plitron have a very good reputation for their technology in taming the toroidal transformer, and OEM to several manufacturers including Bryston, BPT, Equitech. Maybe I should dig a little more around the traps to find out what type of transformer is inside, at 20A, the BIT-20 must be one of those items that you dread moving.

[One and a half]

OAAH, what makes you assume they didn't figure the Torus rating that way to begin with?

Also the receiver on it's own won't exceed the limitations with your power factor correction, yet the Torus will overheat.

As far as I know, all transformers are rated in VA, always have and always will. Static losses can be in watts, since the losses are mainly resistive and are at fixed frequency. The transformer manufacturer has no idea what type of load will be applied, whether it's a lamp or an SMPS. I doubt the rating would include allowance for pulsed waveforms, unless the conditioner has an inverter type output.

[Folsom]

The only rating the Torus has is 2.5a  no VA in the PDF that comes up.

[bjski]

That's good news and a great result for the RM 2.5.

The BIT-20 is a little thin on information from the manual to download, but I see it is a Plitron based device. Plitron have a very good reputation for their technology in taming the toroidal transformer, and OEM to several manufacturers including Bryston, BPT, Equitech. Maybe I should dig a little more around the traps to find out what type of transformer is inside, at 20A, the BIT-20 must be one of those items that you dread moving.

You got tha right.....90lbs .....I was sucking wind when I installed it.

[One and a half]

The only rating the Torus has is 2.5a  no VA in the PDF that comes up.

The torus has a transformer built in.

[Folsom]

The torus has a transformer built in.

And?