Wednesday 30 September 2020

Redefining Fluorescent HID Mercury Lamps


OPEN SOURCE EVERYTHING QUESTION EVERYTHING


Q and A - Researchment Proposal, Questions and Expectations



Depiction of experimental mercury lamps


Q - Let start to be more clear, to have a better understanding. In a previous post you claim that the mercury lamps as a whole represent a mature technology.  What do you try to redefine, which might be the goal of the proposed research?
A - Yes, that is! But the mercury lamps, as a whole, as well as other technologies, have grown and developed their maturity from a commercial point of view. From other points of view, as the interest resulting from discussion in our posts, there is still a room for other developments.

Q - Now it seems to come out the 'non-commercial' interest, esoterics, rainbow colors, and so on... Isn't it!
A - For sure it is! We try to exploit the 'uncharted' side of the high pressure mercury lamps, either those used for lighting, and for UV as well. More exactly we head into the mercury HIDs for using more 'fluorescence' to achieve more 'colors' in their light.

Q - Let we also look back to a previous post and try a comparative description with the fluorescent medium pressure mercury lamp?
A - Yes, here it is: https://lightcommunitylighting.blogspot.com/2020/08/blog-post.html.

Q - What is it intended to be, how to look like?
A - What it is in fact! A high pressure mercury lamp, in a form of a HID lamp, shaped as an ED/BT fluorescent coated bulb with an E39/40 screw cap, or even the E33 size for ED23.5 and ED28 bulbs.

Q - Then what the difference from what is known nowadays as a lamp of this kind?
A - It will have a greater amount of UV in order to bring in more visible light due to fluorescence, or, as case may be, a colored glass too.

Q - And the fluorescent coating?
A - For sure will it be of the type used in high pressure mercury lamp, heat resistant.

Q - Would you expect a variety of colors of light as in the supposed case of the fluorescent medium pressure mercury lamp?
A - No! It will be rather a variety of 'Deluxe' colors, and some few more soft colors. The heat resistant fluorescent powders that convert near UV into visible are very few comparative to those sensitive for 254nm.

Q - Then, what does the constructive difference consist in, if we look at the standard coated high pressure mercury lamps?
A - The experiments are headed for some special constructions of these lamps. Some will be considered to be underdriven and others to be overdriven.

Q - But does not seem strange, if you propose into research to work HID mercury lamps with missmatching ballasts?
A - We do not propose the commercially usage of missmatching lamps with ballasts. If you question something, you have to draw your own conclusion. Lamps will have special construction, as case, for underdriving or overdriving, as well.

Q - What kind of lamps are proposed to be underdriven in the experiment?
A - There will be, on one hand, the common arc tubes used in manufacturing of high pressure mercury lamps for lighting, of medium power. On the other hand, there will be the high pressure mercury UV lamps or even medium pressure ones, of low power. But all have to be mounted inside a vacuum outer bulb of a smaller size than that corresponding for a certain power of lamp.

Q - What are the lamps shown in the depiction on top?
A - The left one is a medium pressure mercury UV lamp of 1000W (as an arc-tube, 145V/7.5A-130V/8.6A) inside a vacuum BT37/BT120 outer bulb. That on right is a high pressure mercury arc-tube of 1000W (7.5A, for general lighting) in a vacuum outer bulb of ED37/ED120 size. There are intended to be run for measurements on magnetic ballasts of 700W (5.4A, for mercury lamps) and on that of 600W (5.5-5.8-6.2A, for sodium lamps), or, even on that for 400W lamps (4.6A).

Q - OK! Let's go into details. How need to be the lamps for underdriving experiments?
A - As an example, you will have a lamp with an ED28/ED90 (outer bulb that usually corresponds to 175-250W bulbs) encapsulating an arc tube used for 400W (3.25A), but in vacuum. Heat reflective coatings are also needed on the ends of the arc-tube. And you will burn it on a sodium/MH ballast (a magnetic one, for the experiment) of 250W (3.00A), a mercury ballast of 250W (2.15A) or even a sodium/MH ballast of 150W (1.80A).
For sure, you will search for if the underdriven arc tube works however at a reasonable high temperature. You expect that the vacuum and the smaller outer bulb will prevent the heat loss of the underdriven arc tube, and this might lead to an arc tube working sufficiently hot, but also with some higher UV emission, at least in the near UV. So, to have at disposal a greater amount of UV for fluorescent conversion.
Consider the second image for them.

Q - How need to be the lamps for overdriving experiments?
A - As an example, you will have a lamp with an ED37/ED120 (outer bulb that usually corresponds to the 400W bulbs) encapsulating an arc tube used for 250W (2.15A), but in an atmosphere of a heat conductive gas which prevents arcing. And you will burn it on a mercury ballast (a magnetic one, for the experiment) of 400W, 3.25A, or on a sodium/MH ballast of 250W, 3.00A.
In this case, you will search if the overdriven arc tube works however at a reasonable temperature, not too hot. You expect that the gas filling and the larger outer bulb will prevent the overheating of the overdriven arc tube, and this might lead to an arc tube working not excessively hot, but also with some higher visible light emission, thus possible not so much UV. So, you have at disposal a greater amount of visible light.
The need of this experiment is for only the case you intend to use a colored glass for the outer bulb, beside of the fluorescent coating.
The third image resambles these at best, but getter is not needed.

Q - And, why do you need to overdrive arc-tubes for the case of bulbs using colored glass?
A - It is expected a broader visible light spectrum from the arc-tube (solely,  no due to fluorescence), so you suppose to have at disposal more wavelengths to be filtered by the colored glass.

Q - Will be also a case of experimenting arc tubes, as there are designed to work, not overdriven or underdriven?
A - Yes, the case will be with only high pressure UV lamps, but not the case of arc tubes used for lighting.

Q - Yes! That ones for lighting are already in use as a mature technology. But what do you look for with those lamps used for UV?
A - Experimental bulbs (in form of ED/BT, outer bulb) need to be build with high pressure UV lamps used as arc tubes inside the ED/BT outer bulbs, either in vacuum or with filling gas.
You need to find out the behavior of the UV lamp (now as an arc tube inside an outer bulb) comparative with the parameters of that UV lamp solely.

Q - So, again would you need the experimental uncoated ED/BT bulbs, as in the case of the experiments with medium pressure mercury UV lamps?
http://lightcommunitylighting.blogspot.com/2020/08/blog-post.html
A - Exactly! For each of particular experiment there is the need of a clear (uncoated lamp).

 


more content to come...



Image of high pressure fluorescent coated colored mercury lamp of 400W with BT37/BT120 outer bulb: www.lamptech.co.uk









Image of Deluxe high pressure mercury lamps
[only for illustration and educative purpose]



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