165v for halogen light - Is this normal voltage for halogen and how do I get 165?

BR-549

Joined Sep 22, 2013
4,928
Have you ever started a fire with a magnifying glass? Oil can do the same thing. It can concentrate heat and light.
 

GopherT

Joined Nov 23, 2012
8,009
Have you ever started a fire with a magnifying glass? Oil can do the same thing. It can concentrate heat and light.
Maybe it can, but do you have evidence or can you point to any science. I'm open to believing it, I just haven't seen anything that makes it more than a wives tale to this point.
 

SLK001

Joined Nov 29, 2011
1,549
No wives tail? You just recited something that makes no sense to me. A mineral glass, quartz, etched by skin oil? I would like to see that experiment. Interesting that there is no solid science anywhere on this.
You want to experiment? Okay, do this:

1) Apply a fingerprint to a quartz bulb.
2) Turn on said bulb for two hours at max output.
3) Observe the fingerprint, now etched into the glass.
4) Confirm etching by trying to remove said fingerprints with various cleaning agents.

Here's a picture of a fingerprint etched in a quartz bulb.

failure14.gif.jpg

Fingerprint: Oils from fingerprints and other contaminations
on quartz bulbs causes a divitrification chemical reaction when
bulb is heated. Quartz glass crystallizes becoming brittle causing
premature glass failure (bulb could explode.) Remove all
contamination from glass before installing.
 

Thread Starter

RogueRose

Joined Oct 10, 2014
375
So since the bulb has a 165v rating on it, would the best advice be to rectify 120vac to DC which would give about 170vdc? Or can it run on 240vac?

DC current should be alright for a halogen, correct?
 

Phil-S

Joined Dec 4, 2015
238
Most well known reputable halogen lamp manufacturers advise handling the lamp with cotton gloves or even provide a paper tag to do it with.
Having had one of these blow apart in front of my face, I now have a healthy respect for these things. Not only would I not touch them with a finger, but a ten foot barge pole as well. There are few reasons to use these for lighting now. The downlighter (MR16 or GU10) types over 20-W get dangerously hot in my opinion.
 

Vague

Joined Jun 1, 2011
2
Most well known reputable halogen lamp manufacturers advise handling the lamp with cotton gloves or even provide a paper tag to do it with.
Having had one of these blow apart in front of my face, I now have a healthy respect for these things. Not only would I not touch them with a finger, but a ten foot barge pole as well. There are few reasons to use these for lighting now. The downlighter (MR16 or GU10) types over 20-W get dangerously hot in my opinion.
You want to experiment? Okay, do this:

1) Apply a fingerprint to a quartz bulb.
2) Turn on said bulb for two hours at max output.
3) Observe the fingerprint, now etched into the glass.
4) Confirm etching by trying to remove said fingerprints with various cleaning agents.

Here's a picture of a fingerprint etched in a quartz bulb.

View attachment 109202

Fingerprint: Oils from fingerprints and other contaminations
on quartz bulbs causes a divitrification chemical reaction when
bulb is heated. Quartz glass crystallizes becoming brittle causing
premature glass failure (bulb could explode.) Remove all
contamination from glass before installing.
I believe the reason fingerprints are bad on a quartz bulb are the sodium and potassium ions from your sweat react with the silicon dioxide of the quartz to form sodium silicate which is ordinary glass with a much lower melting point than quartz.
 

Parkera

Joined May 3, 2016
106
I've worked with quartz glass pressure transducers. These are known for their incredible stability over time and virtually no hysteresis. You are cautioned to NEVER touch the glass with bare fingers. If you do, it's characteristics will taken a sudden shift, requiring re-calibration of the instrument. This shift is measureable with a calibration setup.

Pressure transducers measure pressure by measuring the amount of deflection (usually at the end or tip) caused by applying a physical force (pressure) to the transducer. This implies that touching the glass with bare hands changes the physical properties in some manner, be it thickness, composition or hardness. While I'm not a chemist, I can tell you it is NO WIVES TALE.
 

ronsoy2

Joined Sep 25, 2013
71
It has more to do with the skin oil turning opaque with the exposure to the high temperature. This opaque spot then becomes even hotter causing a hot spot. This hot spot gets even hotter causing the fail. I don't think this is a problem on this particular type of lamp. The skin oil fail is more of a problem on the high pressure arc lamps like are used in video projectors. The pressure in these lamps can be hundreds of psi at operating temperature! In any case you shouldn't have any problems if you handle the lamp by the ends.
 
I've worked with and even designed halogen lamps and controllers for 10 + years. If this is what it looks like, here's what you need to know.
Halogen is used to displace oxygen inside the lamp tube as a shielding gas. It serves several purposes from preventing the filament from being consumed to controlling the temperature of the outer envelope.
Fingerprints are ok, but only if the quartz glass is properly cleaned (alcohol and non abrasive wipe) before it is heated. Oils from skin contact will devitrify the tube, creating a surface which will absorb radiant energy, then overheat and potentially lead to catastrophic failure at that point. Good practice is clean handling, such as cotton gloves.
There is no harm in running these under the rated voltage whatsoever. Life expectancy is inversely related to the supply voltage. The output wavelength will be longer than the specified wavelength. Shorter lengths will result in more visible light, or apparent brightness. At some point below the design voltage, these will emit medium wavelengths which will appear as an orange glow. Since these are typically designed for radiant heating applications, this may be less desirable because the lamps themselves will run hotter and will not transfer energy to the target efficiently. Thus is the toaster oven scenario.
Most cannot be mounted vertically unless they have wound standoffs around the filament to keep it from 'slumping' and contacting the inside wall of the quartz tube.
Another consideration is to be sure these are never mounted rigidly in a fixture as the TCE of fixture materials is generally much greater than the lamp's. As the fixture expands and contracts, a lamp that can't 'float' in it's mount WILL break.
If tour application is for heating, I'd snag these for that price and find a way to use them. They can work in a lighting application only if this was the intent of that particular design. Is there a laser engraved part number on these? I can probably help identify exactly what these were designed for...
 
BTW, these present as an almost completely resistive load, so even low cost dimmers will control them well as long as they are rated appropriately for power. Powering them via a transformer to get a specific voltage makes this into a load with a considerable inductive component and is not for the faint of heart.
 

Thread Starter

RogueRose

Joined Oct 10, 2014
375
BTW, these present as an almost completely resistive load, so even low cost dimmers will control them well as long as they are rated appropriately for power. Powering them via a transformer to get a specific voltage makes this into a load with a considerable inductive component and is not for the faint of heart.
Are you talking about the bulbs I posted or something else?
 
No wives tail? You just recited something that makes no sense to me. A mineral glass, quartz, etched by skin oil? I would like to see that experiment. Interesting that there is no solid science anywhere on this.

Similar halogen quartz lights can be found at a Home Depot or Lowes, etc. I forget the reasoning behind NOT touching the lamp bare handed, but I have had two physically blow up (literally - one even exploded out the front safety glass...I was impressed) while lit. (No, I didn't knock the light over while plugged in.)

These days, it's something of a moot point with the halogen work and flood lights as you can purchase LED fixtures that provide light. And consume far less energy.
 
Bulb - looks just about exactly like this one:


But instead of them being $5-14 each, I found them for $.20 each.... and they have cases of broken ones and I was wondering what the inner metal part is and if it could be used in custom glass blown bulbs like back in the Edison days when bulbs never died...

I was wondering if this could be run on rectified DC from 120AC. Isn't there something like a 1.4141 conversion rate from AC to DC rectification? 120 * 1.4141 would give just above 165v
No small print text on the ceramic end? No model number of manufacturer?
 
Are you talking about the bulbs I posted or something else?
Yes. The photo and description fits perfectly. As far as controlling them, it's most common to use phase angle controllers to control AC. Theoretically, DC should work, but is not a common practice. Depending on what you want to use these for, you may be pleasantly surprised at how well 165 v lamps will work on 120v - no controller needed.
 
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