115/230V voltage switch key for transformer?

The classic term used in Marshall and other Audio Amps is voltage selector plug.

Somebody decided they should be removed from the electrical code. Your left with the voltage selecting fuseholders. try schurter.

Steve

Ouch, ouch, ouch ... really? So they are gone for good?

Those are all way too expensive plus this has to fit onto a circuit board. The fuse holders are large panel mount devices but we'll have no panel.

I could cook up an electronic auto-selector but that would probably blow the cost target as well.

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

| The classic term used in Marshall and other Audio Amps is voltage | selector plug. | | Somebody decided they should be removed from the electrical code. Your | left with the voltage selecting fuseholders. try schurter. | | Steve |

FAIK that old method does not meet current EU safety regulations anymore. So that selectors became obsolete.

Why a slide switch will not do? You can find voltage selector slide switches in which the slider is burried so deeply it can only be operated by a small screwdriver or something like that. Sliding it accidentaly seems next to impossible.

petrus bitbyter

The cost is driven up on the fuse holders because the main use is medical.

Go here:

Page 174 for a triac autoswitcher that will probably come in a little less then the fuseholder, but not much.

Rant Mode: If your angry about this:

Then admonish all the folks who voted for the EU a decade or two ago that y'all got us into this mess of changing regulations from Brussels messing up the electronics industry status quo. I being a USian, had no say in the matter. I like 60 hz center tapped transformers, I like

60/40 and I like incandescent bulbs in my machine shop for safety reasons. I'm now told I can't have any of the above. And worse, now I need 5,000$ worth of testing for a battery pack in a month, plus . I have send them 26 battery packs at 200$ a pack for the test. I have a special place in my heart for that bastard said lead leaches. Well, so does everything else. END RANT MODE.

Jumper?

Good Luck! Rich

Yup.

That's quite a ghastly solution. It requires an additional control transformer and its miscellanea to feed the detectors, plus it requires one of the primary halves to be strong enough to stomach the whole input current when at 115V. Which most transformers can't do.

One of my clients decided to just cut the EU market off many years ago, at least for a while. Seriously. It is also one reason why stuff is often so much more expensive over there because bureaucratic hurdle costs get factored into the price.

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

Not that easy anymore. Slide switches often don't have the respective agency ratings and since they are primary side they must. Also, it is very hard to find any that are rated 260V which is required for countries such as the UK.

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

Very much against code, usually. Unless it's a wire jumper but my client wants to avoid having to open the units every time an order comes in for the "wrong" voltage.

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

On a sunny day (Wed, 25 Nov 2009 08:54:06 -0800) it happened Joerg wrote in :

Solution: Pyrotechnics. Use several wire jumpers, and have 2 hidden set of contacts to blow the right ones before shipping.

:-)

Yeah, the ON circuit is crude, and the SCRs in series are a failure point. But its a start. And from a safety point of view, its got to be more of a hazard then a properly made jumper. Kinda my point.

I take it this is on a linear for noise or cost reasons?

Steve

Two reasons. The cost of transformers is remarkably low, around five bucks for 10-15VA. Can't beat that with a switcher, even considering your own PWM stuff behind it because that only adds a buck or two.

Then, temperature. Beats me but all the places I've called won't endorse more than 50C or 60C for their switcher modules and that's just not going to fly. For some reason my own designs never had such limits but I can't justify the NRE for all the agency testing on this one if we rolled our own mains-connected switcher.

The only 250V-rated selectors I see are panel mount and insanely expensive, such as this one:

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

How about a wall wart? You should be able to find something like that for $10-$15.

The only way to get one in would be to snip the end off a two-prong Christmas extension code, solder it in and strap the whole kludge down with cable ties. Any fire marshall would blow a gasket ;-)

Plus I think wall warts don't like to bake in there.

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

Don't PC power supplies have these? If so, then _somebody_ is making millions of them, and they can't be terribly expensive.

Another thing - if it's inside the case, (i.e., soldered to the PCB), couldn't you put a "No User-Sericeable Parts Inside" sticker, and just set an ordinary slide switch or jumper at the factory?

I once worked at a battery charger manufacturer, and the boss had "designed" a circuit that would automatically switch, depending on what you plugged it into. - a relay, a diode, a cap and a couple of resistors. If you plugged it into 120, the relay didn't pull in, but if you plugged it into 240, the relay pulled in and switched the primaries.

But that's a little parts-intensive, and you're not expecting pathological operating conditions, right?

Thanks, Rich

What exactly is it you're trying to produce? You've given several different conflicting scenarios here. Is the user supposed to be responsible for selecting the voltage? Does it get set at the factory? What code are you trying to satisfy?

Please, Joerg, tell us the "big picture" here.

BTW, how do you pronounce "Joerg?" :-)

Thanks, Rich

Ok, big picture follows:

Unit in fields, outdoors, think farm. The sun is pelting it brutally all day long and the electric stuff sits inside an enclosure, no vents big enough to write home about. No choice, it has to be that way and it works fine in a 120V version.

Client wants users to be able to ideally just plug it into 120 or 240, and not worry about a thing. That ain't going to fly because SMPS modules seem to not be that great. Maybe cheap electrolytics, I don't know, but mfgs don't want to endorse >60C and it sure does get hotter than that in there. Just by the sun.

So, the next best avenue would be a configurable 120/240 transformer because then we can have our own (better) switcher behind that. Unfortunately the cheap voltage selectors have become pariahs.

Configuring at the factory would be ok but it has to be simple, like flicking a hidden switch or reversing an insert. But it (meaning also that switching element) must be code-compliant, in this case UL as well as VDE (CE) plus later some others, maybe Japan. Up to now it was only UL.

Cost is critical. Adding a buck in total is ok, adding five bucks is not.

It's o-umlaut, pronounced just like Archie Bunker and many New Yorkers say "poifect" or "point".

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

Have a dual 120V primaries xfrmer with a relay switched series/parallel connection. The relay rest position is connecting the xfrmer in 240V mode, then you have all the time you need to decide what to do with the relay. Cost: one relay and 10c parts.

But I'm confident you'll find something that won't fit ;-)

--
Thanks,
Fred.

Yeah, two things :-(

One, a primary side relay adds more than those 10 cents. The other is that a brown-out situation would cause the relay to partially let go ... bzzz ... phssss ... *PHOOMP*

Of course I could make a brown-out detector and all that. But things would need to go fast because the transformer is without power during the switch-over.

Did you decide which theremin to build with your daughter?

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.

Yes, sometimes, but as usual, integrated into the IEC connector. Can't use that, no space.

Well, there will be sluggish brown-outs and the like.

--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
Use another domain or send PM.