Tango XE20S voltage rating?

[tonitze]

Tango XE20S

Just wanna confirm with you guys whether this output trafo suitable for DRD 300B. I've been warned that the opt. insulation of this trafo might not be able to take higher voltage of B+. May be you guys have different opinion on this. Thanks.

Toni.

 

[dhaen]

Toni,

I can see why you're worried, 700V is high.
Tango seem to have gone out of business, so I can't find a datasheet - cue for everyone to prove me wrong...
I presume this is the design you are contemplating?
DRD300

 

[dhaen]

I just had an idea:

The idea is to elevate the transformer cores to 200v or so, and enclose the cases so that no one can touch them.
But presumably these transformers look pretty? And you want them on show?
How about enclosing them in transparrent acrylic? It could make for a unique "glassy" design.

May be you think I'm mad? But it would work as long as you leave some distance between the acrylic and valves.

 

[GaryB]

Re: Tango XE20S

Just wanna confirm with you guys whether this output trafo suitable for DRD 300B. I've been warned that the opt. insulation of this trafo might not be able to take higher voltage of B+. May be you guys have different opinion on this. Thanks.

Toni.

Well the Tango XE20S can certainly handle the voltages but it is not designed for use in DRD applications. Its a gapped single ended transformer which can handle quite a bit of DC current. A copy of the datasheet can be found here:

http://www.pmillett.com/images/Tango_XE20S.PDF

Since its designed to run with a lot of DC current, its inductance is somewhat limited and its also physically larger than needed. In the DRD application there is no DC current in the primary so you don't need the same airgap and you can have a lot more inductance.

If I had a pair of XE20S transformer then I'd probably build a more conventional singled ended 300B amplifier and get rid of that DRD capacitor, but thats just me.

---Gary

 

[tonitze]

Dhaen and Gary, thanks a lot for the info.Seems that I have to abundant the DRD 300B project then untill I get the proper trafo and choke from Electra Print.

Dhaen,

Correct!! That the DRD 300B that I would like to try but with the 6AN4.


Toni

 

[ThorstenL]

Re: Re: Tango XE20S

Konnichiwa,

In the DRD application there is no DC current in the primary so you don't need the same airgap and you can have a lot more inductance.

I would like to note that you are quite mistaken. In the DRD application around 90mA standing DC current flow in the primary. I would STRONGLY advise against using a transformer without airgap there, as would Jack Elliano, if he where to read this....

Sayonara

 

[Bas Horneman]

Gary B, I think you are thinking of a Parafeed setup

DRD is a different cup of tea ofcourse.

 

[GaryB]

Gary B, I think you are thinking of a Parafeed setup

DRD is a different cup of tea ofcourse.

Mea culpa - thanks to Bas and Thorsten for pointing out my error. It was early Monday morning and I must not have had enough coffee .

For the DRD circuit it looks like the XE20S would work fine.
Thanks,
---Gary

 

[tonitze]

So, that mean I can use the Tango XE20S safely on my DRD 300B PROJECT isn't it?

Toni.

 

[Bas Horneman]

Yes I would think so. Since the cathode resistor with the 2k2 resistor forms a voltage divider as well..in other words there is not the full 700V across the transformer but probably closer to 500volts.

However I don't know what the voltage spec is for the Tango. But I guess it would be higher than 500V.

 

[tonitze]

Thanks Bas Horneman.In case it doesn't work, what is the worst I would expect. The output trans Kaput?

Toni

 

[Bas Horneman]

Hi Toni,

As far as I know...it won't go out with a bang...but I would not even worry about it being to withstand those voltages...I'm pretty sure that it will do fine...

The worst case would be you touching the transformer and you or someone else being electrocuted!

Regards,
Bas

 

[dhaen]

An important issue in transformer voltage ratings is the potential between any winding and the core/case. It will have been flash-tested at a much higher voltage (maybe 2KV or 3KV) than the rated voltage. However continued use can cause breakdown as the insulation can deteriorate under stress and time.
This is why I agreed with Toni's caution until the transformer's rating was known, and suggested a way to get round the problem if it was insufficient.

The bottom line is: Find the Tango spec. and act accordingly.

NB The peak voltage (with respect to chassis) of this system will exceed 1400V. If Tango say 700V is OK then they will have accommodated for this.

 

[Bas Horneman]

The bottom line is: Find the Tango spec. and act accordingly.

That is very good advice John. But I've never seen a voltage rating on a transformer dataheet (apart from Lundahl)

My transformers are pretty unique in that they have a datasheet. (One Electron) but there is no voltage rating declared. Luckily one can email John Atwood

Best thing to do I think is to post another thread with the heading : "Tango XE20S voltage rating?"

someone out there must know...??

Assumptions have led to many a disaster. However is it not safe to assume that Tango (one of the premier transformer companies on the face of the planet) ...have built this tranny for the 300B which typically has b+ of 400-480Vdc? (and is that not the effective voltage across this transformer, even in the DRD circuit?)

I'm not challenging your way of looking at it John....that is the safest way.....I'm trying to have you guys have a look at my assumptions .

 

[dhaen]

Bas,

I take your points. If this was AE or another live manufacturer, we could simply phone/email and ask. They might say.."don't go above Xvolts.."

Since this thread is all about Tango XE20S voltage rating, why don't we just rename it:
Tango XE20S voltage rating ?

 

[dhaen]

Thread renamed and bumped.

 

[tonitze]

Thanks Dhaen for renaming the thread. More appropriate that way I guess.
Still waiting for somebody replying that they've done it with XE20S. Only then i got peace of mind.

Toni

 

[pmillett]

XE-20 data sheet

Tango is still around. They were re-organized as "ISO / New Tango" a couple of years ago. The only place I know of that sells them is Noguchi Transformers in Tokyo, and EIFL Export (somewhere in Japan).

Unless you speak Japanese, though, I doubt that you can get any info from Tango directly.

Here's the XE20S datasheet:

http://www.pmillett.com/images/Tango_XE20S.PDF

Unfortunately no mention of voltage rating.

Pete

 

[tonitze]

Re: XE-20 data sheet

Tango is still around. They were re-organized as "ISO / New Tango" a couple of years ago. The only place I know of that sells them is Noguchi Transformers in Tokyo, and EIFL Export (somewhere in Japan).

Unless you speak Japanese, though, I doubt that you can get any info from Tango directly.

Here's the XE20S datasheet:

http://www.pmillett.com/images/Tango_XE20S.PDF

Unfortunately no mention of voltage rating.

Pete

That's the problem. Anyway, I'll still continue the project using the XE20S despite the risk involved. If the trafo kaput then that's it.

 

[massimo]

Re: XE-20 data sheet

Tango is still around. They were re-organized as "ISO / New Tango" a couple of years ago. The only place I know of that sells them is Noguchi Transformers in Tokyo, and EIFL Export (somewhere in Japan).

There's a third address in Japan, but you should buy a certain quantity, not just a pair of transformer.
Prices are quite good. Perfect for a gruop buy.

Massimo