Nernst lamps

[SPBrewer]

You need to use a fine capillary tube on the glass bulb, pull down to a full vacuum to remove all traces of Oxygen, then fill the bulb with pure Hydrogen. The tube can then be capped and heat sealed without risk.
An alternative method if a full vacuum cannot be drawn (lack of suitable pump etc), is to pull as much vacuum as possible then fill with Hydrogen - repeat several times to remove air molecules and replace with pure Hydrogen, then seal as above.....

Be sure to video tape the first time you attempt to use, just in case you don't get all the Oxygen out! 

[Shadow Of The Tower]

Personally I still prefer the idea of a constant current source for the glower - it's just easier to build. 

Tell me how

[Siliconous Skumins]

Personally I still prefer the idea of a constant current source for the glower - it's just easier to build. 

Tell me how

Constant current mode SMPS circuit...   

SS

[Shadow Of The Tower]

Constant current mode SMPS circuit...

LOL, if I use that I may as well just keep using a lightbulb as thermistor. The device would be equally as pointless and much simpler to make.

 It would be like running a steam engine by using an air compressor. Not much point in building a low tech alternative to modern technology if it only works by use of electronics.

[Siliconous Skumins]

Constant current mode SMPS circuit...

LOL, if I use that I may as well just keep using a lightbulb as thermistor. The device would be equally as pointless and much simpler to make.

 It would be like running a steam engine by using an air compressor. Not much point in building a low tech alternative to modern technology if it only works by use of electronics.

Heh, true - but it's not the only way. 

No, my still favored way is to use an inductive ballast, which would still be steampunky-old-technology (it's a lump of Iron with a coil of copper wire...). It's not really 'constant current', but close enough, and perfectly suited to negative resistance loads (same as a fluorescent lamp). Best part is that it would be somewhat more efficient than a barretter. That means cheaper electricity bills!

Construction is the easy part - doing the maths to work out the reactance needed for the lamp.... that's the "fun" part. 

SS

[Shadow Of The Tower]

No, my still favored way is to use an inductive ballast, which would still be steampunky-old-technology (it's a lump of Iron with a coil of copper wire...). It's not really 'constant current', but close enough, and perfectly suited to negative resistance loads (same as a fluorescent lamp). Best part is that it would be somewhat more efficient than a barretter. That means cheaper electricity bills!

Construction is the easy part - doing the maths to work out the reactance needed for the lamp.... that's the "fun" part.  

When you figure it out make a few of them...I'd buy one or two

Would this help?

http://www.66pacific.com/calculators/coil_calc.aspx

http://www.vishay.com/inductors/calculator-home-list/

[Siliconous Skumins]

No, my still favored way is to use an inductive ballast, which would still be steampunky-old-technology (it's a lump of Iron with a coil of copper wire...). It's not really 'constant current', but close enough, and perfectly suited to negative resistance loads (same as a fluorescent lamp). Best part is that it would be somewhat more efficient than a barretter. That means cheaper electricity bills!

Construction is the easy part - doing the maths to work out the reactance needed for the lamp.... that's the "fun" part.  

When you figure it out make a few of them...I'd buy one or two

Would this help?

http://www.66pacific.com/calculators/coil_calc.aspx

http://www.vishay.com/inductors/calculator-home-list/

Don't look at me - I have Dyscalculia!   (no really - I do...)


First you need to know the voltage and current required for the Nernst glower - I don't fully recall, but I think it was something like 120V @ 300mA for the potato peeler. You also need to know the mains input voltage, and frequency. Mix and then add the incantation...  So the exact specs will depend on where you are in the world, and the dimensions of the glower bar.

It's a bit like black magic really... 

I can do it, takes me a while with maths, but the problem is I don't have anything to test it with yet.  First I need to get some construction materials and build one or two, see what needs tweaked etc. However it should be fairly straight forward to build and test.



Some pages back on this thread I had an alternative idea, however I don't believe anyone actually tried it before ignoring it...  You can use a single capacitor in series with the load (the glower) as a ballast. It's sometimes done with Fluorescent light tubes, it's not exactly efficient, but certainly no worse than the barretter - probably a lot better in fact.

As I recall, I worked out it was a 8.5uF capacitor for a mains voltage of 230V (European mains voltage), and the glower made by Consciousflesh. A common 'motor start' capacitor would work nicely. The capacitance value (uF) is different for different voltages, I gave the formula to work it out - dig back through the thread if your interested.

SS

[SPBrewer]

Thanks !

With the 15 mm glower the lamp operates at about 118 V drawing 0.3 to 0.4 A . The current has to be limited because of the negative current-voltage characteristics of the ceramic rod. In my tests I'm using a regulated DC power supply and a 100W light bulb in series with the rod as the limiter.  Higher current caused the ceramic to melt and bend

Mr. Consciousflesh,
   What do you consider "Higher Current" in the above statement?  I'm looking at a Baretter on ebay (Item # 350449367771) that's listed as a 1B10 17.  Looking at the specs, it appears to be 1 Amp at 100-170 volts.  If the ceramic material melts above .4A I sure don't want to use a 1.0 Amp Baretter! 

   I remember seeing little space heaters being advertised as "Ceramic Heater"'s.  I've always assumed that they meant they used ceramics as an insulator.  I wonder if they didn't mean ceramics as a heating element?  If so, they should contain a current limiter of some source.

[Siliconous Skumins]

   I remember seeing little space heaters being advertised as "Ceramic Heater"'s.  I've always assumed that they meant they used ceramics as an insulator.  I wonder if they didn't mean ceramics as a heating element?  If so, they should contain a current limiter of some source.

Nope - they generate heat by passing electricity through heating wires embedded in ceramic plates. It's basically to extend the life of the heating element, but is also used to directly heat a convection unit to transfer the heat into the air flowing through, which is driven by a fan. Effectively it's the same thing as a standard fan heater.


Mr. Consciousflesh has not been on the forum much at all, and hasn't been logged in for months. You would be better sending him a PM, depending on his profile, he should get an email alerting him to the PM.

SS

[Shadow Of The Tower]

Don't look at me - I have Dyscalculia!

Yeah me too. Which is why I want someone else to do it.

[SPBrewer]

There is an original Nernst Glower on ebay.
See:
http://www.ebay.com/itm/160929309359?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

[SPBrewer]

That Nernst Glower on ebay sold for $305.00 !

[SPBrewer]

I'm considering the use of the XB1 for my Nernst lamp.  I see it limits current to 300mA and has a voltage drop of 9 to 16 volts per:
http://www.r-type.org/exhib/aai0180.htm

My question, does anybody know what the maximum voltage is that this barretter can handle?
I'd hate to get it and watch it fry because I used too much voltage (110 volt @ 60 Hz).

[Mr. Consciousflesh]

There should be no problems with this barretter since it will be working with only a fraction of voltage from the mains . It should be connected in series with the glower , so the biggest voltage drop will be on the glower  , not on the barretter.  The specification says it should work with a voltage drop from 9 to 16 volt - it means that you should set the length of the glower to achieve this value in normal operating conditions. When experimenting please remember that the wire inside the barretter shouldn't be glowing , it wont die instantly but it will fail eventually .

[SPBrewer]

Thanks Mr. Conscious Flesh.  Can you imagine a Barretter in circuit being pushed to it's limits then the glass enclosure breaking?  As my buddy Marvin, the Martian, would say, "There's going to be a BIG KABOOM!"

[SPBrewer]

Did anybody here bid on these Nernst Lamp Brochures on ebay?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170987322264&ssPageName=ADME:B:WNA:US:1123

I can see that I'm sure not the only one interested in Nernst lamps!   

[Sasquach]

Hey all,

My first post here but I found the topic of Nernst lamps pretty interesting....

Anyhow, for those of you looking for iron wire, there is a very common cheap source I didn't see mentioned anywhere in the thread: J-type thermocouple wire. A J-type is thermocouple is made up of wires of dissimilar metals (in this case, iron and constantan)….temperatures are read by looking at the potential difference between the wires and referencing a lookup chart to tell you temperature (most readers do this automatically).
Anyhow, you can buy the stuff darn near anywhere and for cheap, and in a variety of gages (as thin as 40)....Omega Engineering has a lot of good options as well.

[ricksbulbs]

Hi, all! I am the fellow who was inthe video clip showing how an old Nernst lamp is built. (Rick "C-6" Delair), and just wanted to say, I want to make a potato peeler Nernst lamp myself! Also, I wonder if there is a way to make the original Nernst glowers? We have a few at the Edison Tech center, and I REALLY want to get one going again! Any suggestions are welcome, and out site is www.edisontechcenter.org so check it out. I collect light bulbs, and the Nernst lamps belong to the owner and founder of the Edison Tech Center, John Harnden, bit I am kind of the "caretaker" of then so to speak. John had put a GE NE-35 neon lamp in one saying these just glowed very dimly, with a weak orange glow like the neon lamp, but I know this is untrue. What John saw as a kid, was the heater glowing in a Nernst lamp with a failed glower. Alot of heater failures were due to dead glowers running constantly. The iron wire ballasts had a limited life span as well. One of the Nernst lamps at The Edison has a burned out heater. This is a VERY COOL technology, and is really 'high tech' even today---amazing it was made over 100 years ago! I also love early fluorescent lighting---pre-World War 2 stuff and stuff made during the war, as well as immediate post-war fluorescent stuff is GOLD to us collectors. Collectors tell me as far as they know, I am the only person to have 4 working fluorescent desk lamps, all different makes, from April 38, 1938 (fluorescents were introduced on the market in USA on April 21, 1938!) to about July 1939 era, with the now rare GE (and 2 other makes licensed to GE's patents, Garfield and Dongan Electric) "Thermal Auxiliary" ballasts with a built-in thermal-switch starter. I also have an equally rare January 1939 Westinghouse "Glow Switch Auxiliary" ballast with one of the first glow switch starters, which are ubiquitous starters in most ole fluorescent fittings in the US and UK, etc. I am still looking for GE's other early ballast, same era as the Thermal Auxiliary ballasts, called "Magnetic Auxiliary" that uses a magnetic vibrator or "buzzer" switch starter, also built-in. I made a working replica using a regular choke type ballast and a 24 volt AC coil relay from a rooftop air conditioner unit, installed in a gutted-out old case from ballast for 2 F96T12 slimline lamps that was bad. It works exactly like the original, so kind of MY "Nernst replica" in a way! I hope to find a Magnetic Auxiliary ballast equipped desk lamp or early fixture soon. This old stuff is cool and often difficult to find. Anyway, any reply would be appreciated! Cheers! Rick "C-6" Delair! 

[J. Wilhelm]

Glad to see this thread come back to life.  One of the more interesting Tactile topics and hands-on execises...

[von Corax]

Photos, my dear fellow, photos!

[Barney]

Dear all, first time poster here.

I am currently writing my undergraduate masters thesis on zirconia processing using electricity and have spent almost a year researching and experimenting with the critical conditions for the ignition conditions of what are essentially Nernst Lamps.

I would be very happy to discuss lamp design with anyone still trying to build their own Nernst lamps.

If you're still interested then resurrect this thread with me.
Barney

[SPBrewer]

Mr. Barney,
   Yes we do need to get this thread going again.  I can't remember the supplier for the zirconium oxide - yttrium oxide.   It seems like it was a Chinese Potato peeler.  I can't remember.  I think I have one in my desk, but the center drawer has about 37lbs of other junk on and in it.  It will take me a day or two to read the old messages to get caught up, and to clean out the desk drawer where I suspect my sample of zirconium oxide - yttrium oxide is located.  Will get back to you soon.  Good news, now I have some money to throw into this project. 

Thanks for getting this restarted,
Stan er The Sky Pirate

[Barney]

Hi, again.
I've been looking around the web for 3molar%Yttria stabilised zirconia bars or rods but have not had any success with consumer websites. However there are some nice looking pieces for nice prices on alibaba if you know anyone with import logistics already worked out. http://m.alibaba.com/trade/search?SearchText=ZrO2+rod

I work mostly making samples from powder by slip casting and then solidifying them them using electrical heating. If you want to give that a go this is my ceramic supplier http://www.tosoh.com/our-products/advanced-materials/zirconia-powders

The powders were already in our lab when I started my project so I'm afraid I don't know how much they cost. You might be able to request a 50g sample if you're lucky.

On the subject of filament design I think that the greatest challenge I can foresee is oxidation at the hot ceramic-electrode contact. A solution may be to reduce the zirconia cross section in the center of the filement-bar to cause localisation of heating away from the filament ends.

I hope this gives you some food for thought and I look forward to further discussion.
Barney

[SPBrewer]

I've recently purchased a biography about Nernst.  There was an interesting quote from him about his light.  He said many found it interesting that this was an electric lamp that you could start with a match and put out by blowing on it. 
Stan