Lamp Limiters

[Rubberfingers]

In addition to fireglow/oven lamps, incandescents will remain available for vivariums etc, from pet shops, as the heat is needed.

[John10b]

Interesting, I’ve not really thought much about the “bog standard”bulb over the years but now of course with the changing technology perhaps I need to gen up a bit.
So in terms of the construction, I take it we have among the different types e.g.
1. Filament, vacuum. This I presume is the “bog standard “ Incandescent bulb.
2. Filament, gas (Halogen etc).
3. Etc, Etc...
4. LED
Etc etc
So now I need to understand what the different filaments are made of, and critically what the Resistance is in relation to the Lamp Limiters under discussion.
Finally what could we use if we did not have the incandescent bulbs, which would give us a visual like the bulb.
Cheers
John

[hamid_1]

I don't think we need to worry about running out of incandescent lamps for the forseeable future. Billions and billions have been made. Even if only a tiny proportion survive, that's still a lot of bulbs.

Old stock filament bulbs turn up all the time in car boot sales, sometimes in odd shapes and sizes, like golf ball or candle bulbs with SBC bases, but perfectly usable. Often these old bulbs were made by once famous names like GEC, Osram and Mazda. Maybe one day they'll become collectors' items. At the moment, they're worth very little. Now is a good time to buy them if you come across them. Light bulbs have an indefinite shelf life. You can easily stockpile enough bulbs to last a lifetime.

Another type of filament bulb available new in the shops, as well as the Fireglow ones, are the so called "Antique" bulbs. These seem to have escaped the filament bulb ban for now. I mentioned these a while ago.

https://www.vintage-radio.net/forum/...11&postcount=3

They are sometimes found in pound shops for £1, and DIY stores for several pounds each. I got lucky when Poundworld recently closed down. I bought several "antique" filament bulbs reduced to 30 pence each. They are of course modern reproductions of early 20th century light bulbs, not real antiques. They actually give out less light than traditional bulbs of the same wattage. Quality may be a bit variable, too. I tested all the Poundworld bulbs after buying them. One went bang and took a 3 amp fuse with it. Luckily Poundworld were still open and had some more bulbs left; they exchanged the faulty one without question.

There's a new type of bulb called LED Filament bulb. These have strings of miniature LEDs arranged to look like a traditional incandescent bulb. The effect is quite good, and there's a lot less power consumption and heat. Of course these are not suitable as lamp limiters.

[broadgage]

Originally Posted by John10b

Interesting, I’ve not really thought much about the “bog standard”bulb over the years but now of course with the changing technology perhaps I need to gen up a bit.
So in terms of the construction, I take it we have among the different types e.g.
1. Filament, vacuum. This I presume is the “bog standard “ Incandescent bulb.
2. Filament, gas (Halogen etc).
3. Etc, Etc...
4. LED
Etc etc
So now I need to understand what the different filaments are made of, and critically what the Resistance is in relation to the Lamp Limiters under discussion.

Virtually all true incandescent lamps sold today use a tungsten filament, the great majority are gas filled, some lower wattage types are vacuum filled, and some contain a halogen mixture.
All are 3 types of tungsten filament lamp are interchangeable for use in lamp limiters.

True carbon filament lamps still exist but are very rare and expensive, they are less suited for use in lamp limiters.
Most so called carbon filament bulbs sold on line are NOT in fact carbon filaments at all, but are vintage style tungsten filament lamps, these are suitable for lamp limiters.
"carbon filament" seems to have become the on line term for anything vintage style and no longer refers to the actual filament material.

[martin.m]

Most supermarkets haven't stocked filament bulbs for years. "Cheap" shops like Home Bargains still have plenty of them (up to 60W) with ES and BC bases. They are also available on Ebay but prices have gone up a little compared with a couple of years ago. I found someone selling 10 packs of 60W clear B22 size for £7.50 including postage.

[arjoll]

They're widely available here. Most stores try to direct you to energy saving bulbs, but you can still buy 25-100w for less than NZD1.00 in most supermarkets and hardware stores. I bought a 60w from Mitre 10 for 99c last week to replace one in a wall washer on a dimmer in a bedroom - one of the last fittings I use them in, and mainly because the illumination pattern from a dimmable LED doesn't fit.

[suebutcher]

And there's as yet no problem finding 240V halogen bulbs in Australia. (As long as you ask for a halogen "globe". I've been here 48 years and I still say "bulb"!)

[paulsherwin]

The EU Commission and the UK government have both been pretty gung ho about reducing domestic electricity consumption. Banning incandescent lamps is just the most obvious example - there's a fairly low 900W limit on vacuum cleaner power, for example. The government forced energy suppliers to send out huge numbers of CFLs to their customers FOC, and most of us will have a big box of the things somewhere.

Whether these measures are effective is arguable - the switch to LCD TVs probably had a greater impact than enforced changes in lighting technology (some of which would have happened anyway).

No discussion of the EU or Brexit please.

[broadgage]

Incandescent electric lighting is about to go the way of oil lamps, gas lighting and carbon arc lamps.
All of which are still used today, but only in very limited numbers and not for general illumination of most homes or workplaces.
I can remember when gas and oil lamps were in widespread use and most local hardware shops stocked at least the more popular types of gas mantles, oil lamp wicks and replacement glasses.
Such articles are still available, but only from a handful of specialist suppliers, and not normally from the local shop.

I predict that in decades to come, that incandescent electric lamps will still be available, but at relatively high prices and only from limited numbers of specialist outlets, and not be a low priced commodity sold in every local shop.

I also expect that the choice of incandescent lamps will reduce to a shrinking number of the most popular types. (just as some of the more obscure spares for oil lamps are no longer made)

This has already started, with many rather odd incandescents no longer available.
100 volt GLS
200 volt GLS
70 volt GLS with 3 pin BC cap
12 volt 15 watt BC GLS
10.3 volt twin filament*
240 volt "3 way" bulbs
277 volt GLS are almost extinct, even in America
Series street lighting lamps, ditto.

Are all now almost unobtainable, and tend to be very expensive if located.
*there are several wattages of these on ebay right now, but I suspect a "one of" sale of surplus stock rather than continuing availability.

[Refugee]

I agree.
Some of the power saving measures can never work.
I also agree that LEDs are a big improvement over CFLs. LEDs are even getting better than full size strip lights these days.
Reducing the power of vacuum cleaners will just result in overloaded motors and more waste as well as making the tedious job take longer.

[julie_m]

Limiting the power consumption of vacuum cleaners actually doesn't sound such a bad idea. Manufacturers were boasting of higher and higher power motors, but have a feel of the exhaust air ..... ! It's clear that a fair amount of that energy was going into heating the stream of air, not just moving it. We were all being ripped off with inefficient motors.

The old Hoover Junior managed to clean a house on about 400W (judging by the size of the motor; I haven't got an actual one to hand to check the ratings plate).

[G8HQP Dave]

Power is the wrong thing to limit; it is energy which matters. If your vacuum takes half the power, but needs three times as long to clean the carpet then you have increased energy consumption by 50%. However, power is easier to measure and easier to limit.

Like many here, I have a stock of incandescent bulbs which should be enough to see me out for lamp limiter use. Lighting is almost all LED and CFL.

[paulsherwin]

I still have a few incandescents in use, because they are only used occasionally and for short periods, have good colour rendition, and are instant-on. There's absolutely no point in paying £5 each to replace them with LEDs just for the sake of it, though obviously it will happen eventually.

[PsychMan]

Aren't "Daylight" bulbs (designed for craft purposes) also filament bulbs that would be ok for this application? Available in 100w also

While lower on energy consumption, I haven't found CFL bulbs, or LED for that matter to have much better life spans, as inevitably the cheap electronics in the ballast / driver circuitry fails and renders it useless. I know they're repairable in theory..

[broadgage]

Most "daylight" bulbs are tungsten filament lamps with a light blue glass bulb, they are entirely suitable for use as lamp limiters.
They come in various wattages but 60 watt and 100 watt are common.

A minority of daylight lamps are CFLs with a daylight phosphor, or LEDs designed to mimic daylight, these less common types are not suitable for lamp limiters.

[paulsherwin]

The only drawback with daylight bulbs for lamp limiter use is that they are a bit pricey, though still cheaper than a good LED. They are relatively high quality so should have a long life.

People use tungsten daylight bulbs for crafting and sewing because their colour resolution is as good as you can get, though LEDs have become a lot better in that respect and are now giving them a close run.

The sun is incandescent, I wonder when that will be converted to LED. Joking aside that is why "daylight" incandescents will be around for quite a while.

[julie_m]

I had a friend once who was quite upset to learn that Solar power is actually nuclear power .....

Tungsten filament lamps are approximately black body radiation sources, as is the Sun. The usual type of "daylight simulation" lamp such as you might find in places such as sewing shops is a tungsten filament type, with a clear glass globe and just a thin coat of blue lacquer to simulate the filtering effect of the atmosphere. This produces a continuous spectrum, with every possible wavelength present; as opposed to the discrete wavelengths emitted from monochromatic sources or single phosphors.

That being said, there were some very good compact fluorescent lamps made using a fancy blend of phosphors which produced a very good spectrum with few gaps. (You can shine the light from a source through a prism to separate the wavelengths properly, or just look at the playable side of a CD for a rough impression.) So it's definitely possible to make a low-energy daylight simulation lamp with blended phosphors and perhaps multiple excitations; whether it's economically worth it is another question.

I suppose even if they stopped making tungsten filament lamps altogether, it would be possible to build a PWM current-limiting power supply that would measure the load and adjust its duty cycle so as to do exactly the same job as a lamp limiter! (All the bits exist already, in grid-synchronous inverters as used on solar arrays. The box in my loft is keeping track of exactly what the "real" mains is doing, and making sure it's always pushing energy out through its own mains connection, whatever is coming into it from the solar panels.)

So you could have an energy regulator without using a lamp limiter. It could even incorporate direct (manual or programmable) adjustment (just like a variac), and simulate higher-wattage lamps for heavier loads.

It would be supremely ironic, though, if such a piece of test equipment wound up using more energy than the traditional lamp limiter .....

[John10b]

Thanks Julie it certainly would be much more complex than the “bog standard “ bulb, but I asked the question and got an answer, many thanks. Just a small observation, you won’t have that instant visual warning, as with a bulb, or I’m I misunderstanding?
Cheers
John

[G6Tanuki]

If mains-incandescents go the way of the dodo there is an alternative 'limiter' approach.

Wire the primary of a suitable transformer in series with the load, and attach 12V/24V car bulbs to the secondary of the transformer.

With no bulb-loads the series transformer behaves like a choke, and only the magnetisation-current will flow through the primary. Consuming power from the secondary increases the primary-current accordingly.

A range of bulbs will give easy control over maximum current, from the dual-filament 6/21Watt side/brakelight bulbs up to H4 dual-filament 60/55-Watt headlamp bulbs. I use H4 bulbs for current-limiting in 12V applications, the local garage occasionally gives me a load of 'one filament failed' ones they've replaced.