Neon Sign Transformer

[Wildfuzz]

Have any forumites got any working knowledge of very high voltage transformers. I need advice on one which although new has no output. I am not using it for a neon sign so if you have a good working knowledge of this subject please PM me for further details and my questions.

 

S.

[TheQ]

I reckon he's making his own tazer.....

 

Either that or he's going to put a cattle fence round the broads to keep all the Hullabaloos out.

 

PS I've used High Voltage transformers in various bits of Radar and  CRT displays, so if you don't get a better offer then give me a call...

 

[Wildfuzz]

42 minutes ago, TheQ said:

I reckon he's making his own tazer.....

 

Either that or he's going to put a cattle fence round the broads to keep all the Hullabaloos out.

 

PS I've used High Voltage transformers in various bits of Radar and  CRT displays, so if you don't get a better offer then give me a call...

 

Not quite.......

 

And thanks I will.

 

S.

[grendel]

I dont reckon the high voltage transformers I am used to will help, anything up to 132,000 volts, even 265,000 volts, the problem is they cost a bit and top out at about 20 ton plus. I am of course talking about electricity distribution transformers

[BroadScot]

I think the one Stuart means is the boxed choke/capacitor type?

[FairTmiddlin]

Just Google Neon sign Ballast Transformer

E.G   https://uk.proflamps.com/en/Products/Applications/Ballast-&-Transformer/p/50000301779116/?gclid=CjwKEAjwmMS-BRCm5dn51JLbp1wSJACc61tF_o1wKx9zEMRDe5rILaHUHgGrCld9MqhKT_VZdoMOBBoCKnnw_wcB

[Wildfuzz]

The one I have is below, I am using it (or trying to) for fractal pyrography, no lectures on safety please, but having set it up last night, the transformer is working (humming) but there is no output to the two leads, now I think this is due to some sort of internal safety circuit, but having trawled the internet and you tube on similar arrangements all the other users have a direct output. Due to the high voltage and inherent risks I have no wish to fiddle so hence the question for advice. I cannot go to the supplier as it is not being used as intended! So stuck

[riyadhcrew]

Hi Stuart,

Maybe the ''open circuit protection'' is preventing the output from turning on.

[Wildfuzz]

30 minutes ago, riyadhcrew said:

Hi Stuart,

Maybe the ''open circuit protection'' is preventing the output from turning on.

That was my thinking, does this mean that it is a "no go" with this transformer?

[riyadhcrew]

That I don't know Stuart. Maybe Iain or Alan can answer that.

[BroadScot]

From what I can see Stuart that is possibly the reason. If that is the unit it looks like it has overheated on the right hand side. Time to spend pennies I think.

Iain

[TheQ]

I'd agree the " comprehensive safety protection" is likely to be doing it's stuff and shutting the output off. Making this unit unsuitable for your task

[Viking23]

The unit has a constant current output, which means there has to be a minimum resistance so that this current can flow.

With constant current, the output voltage will increase until this current is met, as the current hasn't got to the limit, the open circuit over voltage circuit protection will shut the unit down.

What are you trying to do? there are other ways of generating high voltage, so what voltage do you need, does it need to be constant? what current capability etc?

 

I designed and built a mains powered taser once  but field trials wern't that good, as they couldn't find a socket on the street to plug it in, and if they did, the offendant just moves back until it unplugs it's self lol...

 

Richard

[Viking23]

Had to look it up..

see :-  http://makezine.com/2015/06/10/burn-fractal-patterns-plywood/

You need two microwave transformers... see above.

This is extremely dangerous if left unattended, an earth leakage trip on the supply will not give you any personal protection if you touch the output. 

 

Richard

[BroadScot]

2 minutes ago, Viking23 said:

Had to look it up..

see :-  http://makezine.com/2015/06/10/burn-fractal-patterns-plywood/

You need two microwave transformers... see above.

This is extremely dangerous if left unattended, an earth leakage trip on the supply will not give you any personal protection if you touch the output. 

 

Richard

Death by misadventure comes to mind,Richard!! Steady laddie you'll scare Stuart alf to death !

[grendel]

I would suggest an insulated case inside which it can perform its marvels, how about a transformer from an older 'vintage' neon light, that does not have the modern safety protection (and rubber boots and HV live jointers gloves)

[BroadScot]

6 minutes ago, grendel said:

I would suggest an insulated case inside which it can perform its marvels, how about a transformer from an older 'vintage' neon light, that does not have the modern safety protection (and rubber boots and HV live jointers gloves)

Some of those old neon boxes had a lead glass link (similar to the ones inside old storage heaters) that melted if the choke overheated!

[Islander]

Stuart, please be aware that should you go down the microwave transformer route that salvaging them from scrap microwave ovens can be deadly!!! Having worked on Panasonic and Sharp ovens most failures were caused by diode shorts causing fuses to blow. This more often than not left the large capacitor in the high volt circuit fully charged. This can be lethal if it discharges through you. This capacitor can hold its charge for weeks in some ovens so please be very careful. We don't want a fried fuzz on the forum!

my qualifications will now be out of date but then only commercial ovens get repaired these days where as scrapped ovens were put through our workshop and made safe before sending for scrap, most now are dumped or taken to recycling centres.

I must admit this method will be amazing to watch and with care I'm sure you will succeed. 

Colin

[TheQ]

Having serviced the commercial microwaves used in Tesco Cafes and staff diners I'd agree with everything Islander says..

[Wildfuzz]

Thanks for the advice, yes I decided not to touch the microwave transformers for obvious reasons, the neon transformers are the way to go as they are relatively safer to use, what I hadn't considered was the circuitry protection as mentioned above and my research had not brought this up prior to purchasing.

 

The voltage required for the fractal pyrography is the 10,000 volts maximum as allowed in the Uk as wood is not a good conductor. So I purchased the unit shown and have been thwarted by the HSE.... perhaps rightly so! I guess I will have to scour for an older type of transformer as definitely not touching the microwave types.

 

Anyone who has not see this in action have a look on "the tube" some of the practitioners are very "Heath Robinson" and I have a very healthy respect for "electrickery" so am attempting to make this a safe as possible, hence the problems.

 

Again my thanks.

 

S.

[ranworthbreeze]

Hi Stuart,

Could you use a HT coil out of a car or an HT coil out of an old TV? 

Regards

Alan

[MauriceMynah]

53 minutes ago, Wildfuzz said:

So I purchased the unit shown and have been thwarted by the HSE.... perhaps rightly so!

Yes indeed, It's the thwart that counts.

[BroadScot]

39 minutes ago, MauriceMynah said:

Yes indeed, It's the thwart that counts.

I see your repaired PC didn't install a spell checker,MM

[Jim]

I bought a similar transformer as an emergency replacement for a 24Vac IR lamp. It would output no voltage until it detected a load 

[Wildfuzz]

1 hour ago, Jim said:

I bought a similar transformer as an emergency replacement for a 24Vac IR lamp. It would output no voltage until it detected a load 

Yes this seems to be the problem, there is no load as the patterns are created by the high voltage in an almost dead short across the wood. There are no older type transformers around that I can find, and I know of no way to circumvent the open circuit protection........