fluorescent light question

In old style long fluorescent tubes, you had the tube plus the starter & the choke/ballast.
What's happened to the starter & the choke/ballast in the
current compact models?
Also I had heard that the old style tubes were more efficient than regular bulbs. But if you frequently turn on & off then they are no longer efficient because the starter takes a lot of electricity while starting the light. Because of this it was not advised to use these in places like toilets etc, where you don't keep them on for long periods after turning them on. Is this still true for the CFL's?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You've gotten some mixed information. Here's the situation with regard to current fluorescent lamps --
- Starter, choke/ballasts (electromagnetic ballasts) have been replaced by electronic ballasts that operate the lamps on high-frequency power (typically 25 kHz and higher). That makes the lamps more efficient by a few per cent and allows the ballasts to be small in size and low cost. Compact fluorescent lamps (CFLs) with integral ballasts, which are the kind designed to screw into standard medium base sockets, are a good example of an electronic ballast application that takes advantage of the small size and low cost.
- Frequent starting used to make a difference in fluorescent lamp life; but it's no longer a big factor. Electronic ballasts are designed with starting circuits which carefully start the lamp plus fluorescent lamps have longer rated lives anyway. CFLs are typically rated for 10,000 hours; linear lamps for 20,000 hours or more.
- It's a myth that any type of electric lamp draws significant power when it's turned on. Incandescent lamps draw a higher current for a fraction of a second; but there's not enough power in that pulse to make a difference in anyone's electric bill even with a hundred lamps in the house.
As a lighting designer, I now treat fluorescent lamps as I treat incandescent lamps. If the light is not needed, turn them off for both cost and energy savings. A house which was built new four years ago and for which I designed the lighting has 75 fluorescent lamps -- most are used for indirect room lighting on gloomy days. But I put fluorescent lamps in the bathrooms, closets and other areas where the lamps are turned off and on numerous times each day. There have been no lamp failures of either the linear or CFL types to date.
TKM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
<snip>

Whats the current technology for linear flourescents? My Dad put in linear single tube fluorescents all the way around the living room in an alcove. These lamps have the twist in starters. The wiring has deteriorated (brittle) and I'd like to either rewire these or replace them if the technology has moved on. I suspect it was these old fluorescents that were known for the sizable turn on surge.
Jeff

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The current technologies for linear flourescents vary widely by country. The OP and first response look like they are from different continents with completely different mains voltages, where usage of the technologies are consequently quite different. You need to qualify such questions and responses by the country, or you're talking at cross purposes.

No fluorescents have ever had a sizable switch on surge. It's an often quoted myth.
--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 3/21/07 11:15 AM, in article 0DeMh.16044$ snipped-for-privacy@newsread3.news.pas.earthlink.net, "Jeff"

I believe you to be mistaken. The ballast limits the current flow so that even if there were a short between the ends of the tubes, there would be a high current alright but not a stupendous one. I am not an expert on this, but I would be surprise if such current would be mo9re than three times that of operating current.
If there is anything that could be called a surge, It occurs when the starter contacts open up. The interruption of current flowing in the ballast produces a voltage spike that strikes the discharge through the tube.
Bill -- Fermez le Bush--about two years to go.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Actually, with a plain reactor type ballast, current draw is barely more. At least this is what I found testing a 5 - 9 watt CFL ballast shorted. The problem is all the voltage drop is over the ballast and it heats up quick. An electronic ballast may not take to shorting at all.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

He probably has T12 magnetic ballest fixtures. The easiest replacement is T8's. You can get replacement T8 electronic ballests that you wire in the existing fixtures. The bulbs have a smaller diameter (8/8" vs the T12's 12/8" diameter) they have the same length and same connectors as T12's. If you are worried of the condition of your existing fixtures, you can get new fixtures that will accommodate T8's right out of the box. T8's with electronic ballests are more efficient and put out better light than T12s, and I believe the bulbs also have less mercury (better for the environment).
The absolute leading edge would be T5s, however there are other concerns with them, you must replace the fixtures (different length tubes) and the equipment isn't as run of the mill as T8's.
The turn on surge is negligible in any light. Turning them off for 5 seconds would save energy. However restarting a fluorescent light is hard on the lamp's life.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I thought I read somewhere that T5s are actually less efficient than T8 bulbs.
I know that electric utilities are generally no longer offering incentives to install T8 fixtures in commercial buildings as T8s are the default for new buildings and remodeling.
Brian Elfert
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

On electronic control gear, there's no difference. T8's on magnetic control gear are around 10% less efficient. (The T5HE and T5HO tubes only run on electronic control gear.)
T5 tubes, having a thinner light source, enables luminaire optics to be designed to direct the light more accurately, which can mean less wasted in spillage and reabsorbtion into the tube. This can make T5 luminaires more efficient even when the tubes themselves are the same. T5 tubes are still more expensive and tend to have a rather more limited range of colour temperatures and CRIs available, so unless the thinner tube size is an advantage to you, T8's are probably a better choice at the moment.

In the UK, T12 luminaires haven't been available for around 25 years now. T12 tubes are available for old luminaires, but they are low volume products, and many stores no longer stock them. Almost all our T12 luminaires can take T8 tubes anyway (this is only true in 230V countries, and not in 120V countries).
--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Andrew Gabriel wrote:

What about in the US and 120v (autotransformer ballasts)? Can I put a T8 tube in an old T12 fixture (with starter)? I see that there are energy savings by going to T8, even with using a magnetic ballast. Are starters dead, and everything instant start now? In my home I've gone totally CF and hadn't even thought about linear fluorescents.
Jeff

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
writes:

No, you can't put a T8 tube in a fixture powered with a T12 ballast and starter. The voltage and current values that the ballast provides are different and T8 lamps are not designed for starter circuits.
You could replace the ballast with one designed to operate T8, remove the starter and put a T8 lamp into the fixture though since the lamp length and sockets are compatible.
Starter circuits are virtually gone along with magnetic ballasts since electronic ballasts which are now smaller, lighter, more efficient and less expensive don't need starters. They can be designed to start fluorescent lamps in either instant start or rapid start mode.
TKM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I don't know for sure, but I don't think so. T8's in 230V countries were designed for exactly this. They are reduced power but same light output as the original T12.
On US 120V supplies, control gear is more complex and there are more different designs available, and I suspect it wasn't possible to design a lower power tube which would retrofit into these different control gear designs are work safely and reliably. The US T8 tubes are even lower power than those used in 230V countries and hence produce less light than the T12's of the same length. That may be why T12's are still popular in the US, but very rarely seen in the UK nowadays.

Starters still very common on 230V supplies. There is an EU directive requiring improvements to control gear efficiency over a number of years, and originally it was though this would render magnetic ballasts obsolete. However, manufacturers just made them more efficient so they continue to meet the specs. Given they are much cheaper and more reliable than electronic control gear (and from what I hear, much more reliable than US magnetic ballasts which are inevitably more complex due to lower mains voltage), they continue to be used. Magnetic ballast instant start has never existed in the UK, and I don't recall seeing it anywhere else other than the US.
--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Wow. Time to upgrade that system. I can imagine how the lamps must blink, flash and flicker at turn-on. But upgrading is relatively easy and a new system will be 20-30 per cent more efficient. For the following, I assume you now have 4-foot lamps and simple strip or channel fixtures. You can choose to keep the existing strip fixtures; but I would recommend replacing them so you have new lamp sockets too. A good replacement lamp is the 32 watt T8 which is also a 4-foot lamp. That lamp is easy to find, relatively inexpensive, rated for 20,000 hours life and is available in a warm color (3000K, CRI+ is best for home use in my view).
Power the lamp with an electronic instant-start ballast. You can use either a single-lamp or a two-lamp ballast, but the wiring with the two-lamp ballast is a little more complicated since there is a ballast just in ever other strip fixture. However, that's the cheaper solution. I've used the Universal electronic ballast B2321120 RH-A quite a bit. Google that catalog number and you'll get the technical specifications, wiring diagram and some sources of supply.
No, there was no turn-on power surge with your old system -- just a few current pulses as the starters operated.
TKM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
TKM wrote:

I think so. Installed back in the 40's.
I can imagine how the lamps must blink,

A mix of lengths as the cornice goes around corners. Mostly 4' and perhaps the other was 18". Dad liked fluorescents and used them throughout the house. Sometimes as auxillary lighting (as in the cornice lights, boy did the room light up when they were on!) and other places as the primary.
You can

Thanks.

I'll do that next time I'm back there. I'm striking out on googling that number, or part of it. I did find one on Ebay for $28.00. Is that the going rate? The one ballast for two fixtures is sounding reasonable!
Google that catalog

I remember a lot of flickering.
I wonder where that rumour came from.
Jeff

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
| As a lighting designer, I now treat fluorescent lamps as I treat | incandescent lamps. If the light is not needed, turn them off for both cost | and energy savings. A house which was built new four years ago and for | which I designed the lighting has 75 fluorescent lamps -- most are used for | indirect room lighting on gloomy days. But I put fluorescent lamps in the | bathrooms, closets and other areas where the lamps are turned off and on | numerous times each day. There have been no lamp failures of either the | linear or CFL types to date.
It's good that *FL lamps today have quick start and none are wasting power or lifetime for frequent starts. Even I would use *FL in certain places like bathrooms where it isn't a long duty task light. But where eye strain can be an issue, like the shop or kitchen, I'll put in a token FL lamp for area lighting, plus many low voltage halogen spot lights to give real light to where I need to work.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

While it was ineffecient in many applications, that myth of inefficiency due to electricity-on-start was debunked long ago -
It was actually the total efficiency considering the cost of labor and materials for replacing bulb and ballast and switch using the old style ballasts, bulbs, and switches - in short, the old ballasts and bulbs only had so many starts in them, not by design, but by typical application and limits of materials. I have seen two studies addressing efficieny in fluorescents - One study had four hours use run time between starts or shut it off, another three hours for maximum efficiency (not electrical efficiency).
We used the three hour criterion for many years - but wide-spread use of electronic ballasts and better bulbs have pretty much removed the "stay-on-time" program for equipment put in in the past decade . If you hire an electrican to change your old-style ballasts, you are probably still in that two hour range -- but that leave-it-on-for-efficiency has a bit more to it.
A fluorescent light can be very inefficient and costly if the total package is considered in certain applications - e.g., put fluorescents in your dining room instead of incandescent, and the $5000 fine-wood table finish embrittles and the color fades in the higher-UV light. Net energy saving from bulb-to-bulb swap for 5 years - $ 50 a year saved. Net efficiency over 5 years - $ 50 saved from electricity, $ 5000 lost due to table damage, net efficiency is a loss of $4950.
Draperies, silk lamp shades, and some plastic shades absolutely also do not like fluorescent lights, nor does fine art - and many things in bathrooms are plastic and will yellow in fluorescent light.
Use of those bulbs around that kind of bulb results in a loss far greater than any savings from a smaller light bill.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Hello, and while I can't comment on the above, I can say the only thing stopping me from exclusively using fluorescent fixtures in my home is that my eyes quickly get fatigued while reading under artificial electric light other than incandescent. Sincerely,
John Wood (Code 5550) e-mail: snipped-for-privacy@itd.nrl.navy.mil Naval Research Laboratory 4555 Overlook Avenue, SW Washington, DC 20375-5337
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
|> Draperies, silk lamp shades, and some plastic shades absolutely also do |> not like fluorescent lights, nor does fine art - and many things in |> bathrooms are plastic and will yellow in fluorescent light. |> | Hello, and while I can't comment on the above, I can say the only thing | stopping me from exclusively using fluorescent fixtures in my home is that | my eyes quickly get fatigued while reading under artificial electric light | other than incandescent. Sincerely,
That happens to me, too. This has been said to be due to things like poor color and flicker. But what I believe is the true cause is continuity of the spectrum (specifically, lack thereof). FL light has 2 narrow and 1 wide spike in the spectrum, with a gap in between. Eyes (and especially when corrective lenses are applied) do not focus all colors uniformly and will tend to focus somewhere in the middle of the nornally continuous white light spectrum. However, a spikey spectrum creates a situation where there are 2 or even 3 distinct focal zones, and the eye wants to jump between them. This happens with sharp edges of black on white where the boundary is present in all the spiek wavelengths. What the eye sees is disjoint boundaries, and thus it tends to jump in focus. The fatigue is from the eyes doing a lot more focusing work (including opening and closing the iris more to try to find a consistent focus).
If you can't have broad continuous white light, then what you need is to confine the spectrum to a single color, red or green. Red is actually best, but green works reasonably well. A true monochromatic yellow would also work (e.g. not a yellow made from mixing red and green). One way to get such light is a deep color gel over a FL light source. Another is using single color LEDs (all the same color).
I have hypothesized that a mix of a sufficient number of single wavelengths would approximate a continuous spectrum well enough for the eyes to no longer have this problem. A future project plan is to build a light box made up of a large number of different LED chips. I've found at least 22 distinct wavelengths I could get some LEDs in. Then I'll need to balance them to achieve some approximation of white.
I experienced the above problem with a light source based on a white LED powered directly with DC. So I know flicker is not the issue (despite the fact that I can see it in virtually all FL lighting). I also experience it with CRT screens where I have addressed the issue with selective colors for the text so that the boundary between text and background is only in a single color (remaining colors are then at a uniform level and present no edges at the text). I can have red text on black, or I can have yellow text on green and it's the same red edge. Cyan text on white presents a red edge in reverse (but that's too much light for the available contrast). Magenta text on white (green edging) almost works. I end up using orange on dim green most often.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
| A fluorescent light can be very inefficient and costly if the total | package is considered in certain applications - e.g., put fluorescents in | your dining room instead of incandescent, and the $5000 fine-wood table | finish embrittles and the color fades in the higher-UV light. | Net energy saving from bulb-to-bulb swap for 5 years - $ 50 a year saved. | Net efficiency over 5 years - $ 50 saved from electricity, $ 5000 lost | due to table damage, net efficiency is a loss of $4950. | | Draperies, silk lamp shades, and some plastic shades absolutely also do | not like fluorescent lights, nor does fine art - and many things in | bathrooms are plastic and will yellow in fluorescent light.
I was under the impression that FL light blocked UV down to the level of IN light. Is this a wrong impression? If so, then maybe we need to add more UV blocking or restrict these lights more so in certain places.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
|

|------------------------------------/-------------------------------------|
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.