Fluorescent lights

[Boac]

Seeking an electrical whiz who can tell me roughly what the consumption of a 15W under-unit kitchen fluorescent striplight would be. (Answers of '15W' are declared null and void....)

I am debating whether it is worth replacing mine with LED tubes. I have been plagued with tube failures - I have been turning the lights on and off as required, but my local electrical shop said better to leave them on all day as they "only use 15W" and it would be cheaper than blowing tubes. This, of course, only works if the ballast resistor does not eat too much.

[19downbubble]

For an old-school T12 with magnetic ballast, for 40W tubes the ballast adds around 16W (but one ballast can handle more than one tube). Newer-school T8s paired with electronic ballasts are way more efficient. I don't know if the ballast consumption scales with tube power.

[Boac]

Thanks, 19 - how do I find out if my 15W fittings are 'new' or not? Are the ballasts easily identified?

Assuming a 16W load on each of 4 fittings, then, my '60W' becomes 120W and makes LED a little more attractive. I understand the change primarily just needs the ballast cutting out of the circuit? Anyone made the change?

[500N]

BOAC

I did some research on the various types of lights and costs of running them and all other associated
cost of ownership about 6 - 8 months ago.

Some good info on the internet if you manipulate google with your searches.


I have managed to work out exactly how much it costs to run the lights / electricity in my house per day.

[19downbubble]

Sorry not to be clearer. T12 is the traditional 1.5-inch diameter tubes. T8 are the one-inch diameter tubes. T5 are the 5/8-inch diameter tubes. For all the farting around going from a T12 to a T8 tube, as you note you're probably better off going to LEDs and ignoring the ballast. I only ever replaced circular flourescents with LEDs, so the ballast came out with the tubes. So I can't help you. I do know there are direct replacement LED tubes that work with old magnetic and new transistorized ballast. Others need the ballast to be taken out of circuit. Also, in some jurisdictions you must label the light fitting to indicate that it will no longer work with the tubes it was designed for.

Finally, you may need to know whether you have an instant-start ballast, hence a shunted connection: many "direct replacement" units don't like them either.

So I'd probably replace the fitting at the same time, to stop my head exploding.

Incidentally, my LEDs can dim and change color temperature: I thought it was a pointless feature, but actually I use it all the time.

[unifoxos]

What to you use the colour change for?

[19downbubble]

3500K when I need to work with colors accurately. 5500K during the day and when cooking. 2700K in the evenings.

[Boac]

Great stuff, all, thanks. Next task is to try and work out which sort of ballast I have and which of the three LED choices ('a/b or c' I gather) I should make - if at all - it might work out cheaper short-term to just 'go with the flow'.

[OFSO]

Changing to LED's - one factor is what colour of light is available where you live. France seems to lead Europe (shock horror consternation) selling LEDs giving colours ranging from hard blue actinic to mild yellowy colour. I have changed 90% of our internal lighting (and a lot of the outdoor lighting) to LEDS. Even the sculpture studio has brilliant LED floodlights which are neutral in colour - essential for painting which is also done there.

[jimtherev]

Interesting, OFSO. Do you mean that the lamps give a good approximation to a true broad-sprectrum 'white' light, or just have a clever mix of fluorescers (?sp) so as to appear to give that impression?

[OFSO]

Don't ask me what I mean, I'm half way down my usual single malt whiskey before going to bed. However I'd advise anyone buying any kind of light source to go into a large DIY store and check them out when lit. And the range of LED 'temperatures' these days is quite large, from blue-white to yellow.

See living room below for old picture of mix of LED's and eco-flourescents. the latter have now been changed: we are all LED.

[500N]

OFSO

"And the range of LED 'temperatures' these days is quite large, from blue-white to yellow."

Yes, noticed that as well. It is good, sometimes even I like a Warm, yellow light, other times
like work areas and outside I like a Bright WHITE Light.

[OFSO]

I designed the lamp bases also (smirk) although they were made by a cabinet maker. All on an auto-switched network: between 07:00 and 24:00 they turn on once the exterior light level falls below a pre-determined threshold.

[OFSO]

The pyramidical base designs are copied from a 25th dynasty wall-painting made probably during the reign of Ashurbanipal, and which was found on the house walls of the physician Up a-Ur Asole, (approx 662 BC) who was believed to be the first doctor to compound medicines in suppository form. Although they were somewhat smaller.