Already doing that. Now people will start running mercury lamps on mh ballasts.

Can this be done without any other "adjustments"? If so, maybe things aren't that bad after all (as far as MV goes...)

From what I understand, under 175 watts, if you match the current of the ballast to the arc tube as close as possible and remove the ignitor, like on a pulse start ballast, it will work. It's funny because the idiots banned MV ballasts but you can still run them on MH ballasts in most cases. So the ban then is basically totally pointless which is not surprising since it takes stupid people to do stupid things. There are always ways around things and this asinine ban is no different.

I agree they should be available for hobbyists, just like leaded gas is available for off-road use. 

why don't they try to improve the efficiency of the already proven magnetic ballast technology? I mean really, 30-40 years? You can't touch that!

Because, they can't.  They already have to the extent that's commercially & realistically feasible. The bottleneck is in the lamps now.

Lamp efficacy increases by over 10%(for 4', more for shorter, less for longer) from high frequency drive, because the cathode loss is reduced. I believe this is the most important reason HF is being used. This was known as far back as 1970s, but back then, creating HF energy couldn't be done efficiently. 

NEMA premium efficiency electronic ballasts are already 90%+ efficient and I think the GE's Ultra Max-H 6 lamp ballast is 95%+. 

0.92(ballast electrical efficiency) x 1.1(lamp efficacy gain factor from using high freq) =101.2%, so even if they can make a magnetic ballast with zero loss, they still can't keep up. 

See page 7 on http://www.lrc.rpi.edu/programs/NLPIP/PDF/VIEW/SREB2.pdf

They're already stretching the practical limits of efficiency on things that still run on line frequency like induction motors and pad mount transformers. 

Since energy is the greatest expense in lighting (for lights themselves + heat they impose on A/C) users have interest in cutting overhead. 

Unlike your computer power supply, you can't upgrade substations and transmission wires whenever you feel like it, so utilities want to squeeze the most out of existing infrastructure.  When they say "there isn't enough electricity", they actually mean that the capacity of distribution system can not keep up, so not using electricity at all in January won't make any difference in shortage in August, because you can't "stock up". 

@Luminire: This is valid only for low pressure lamps. High pressure ones need to be fed by low frequency anyway, so there the magnetic still keep up well in terms of efficiency.
But what magnetic ballast are lacking behind high-end electronic ones is the "intelligence": Ability to feed the lamp by stable setup till more progressed wear (mainly HPS),
ability to reliably detect and shut down lamp at it's end of life before it become a danger (important mainly for QMH),
wear the lamp less (lower crest factor, more stable operating temperature,... - all types),
modify the actual lamp power so, the lamp over it's life deliver constant luminous flux (so save energy during the more efficient part of it's lifetime)
and other features improving the system operating economy, safety or increasing the lighting quality.

Medved: I never knew that electronic ballasts for HID lamps can prevent the arctubes of metal halide lamps from exploding. I only knew of preventing phenomenons of EOL (Like cycling or DC), no flickering, no color shift of the lamp, etc...

@Luminire: This is valid only for low pressure lamps. High pressure ones need to be fed by low frequency anyway, so there the magnetic still keep up well in terms of efficiency.
But what magnetic ballast are lacking behind high-end electronic ones is the "intelligence": Ability to feed the lamp by stable setup till more progressed wear (mainly HPS),
ability to reliably detect and shut down lamp at it's end of life before it become a danger (important mainly for QMH),
wear the lamp less (lower crest factor, more stable operating temperature,... - all types),
modify the actual lamp power so, the lamp over it's life deliver constant luminous flux (so save energy during the more efficient part of it's lifetime)
and other features improving the system operating economy, safety or increasing the lighting quality.

As you said, high-end electronic ballasts.  The cheap POS electronic ballasts that are often come OEM, at least in residential and lower end commercial fixtures lack many of these features, the only real difference between these and magnetic ballasts is poor reliability.  Tough, you can't beat the energy savings of a non-functional fixture with a dead electronic ballast 

I would not say directly "prevent", but reduce the probability, so proper mechanical protection measures have to be still followed. Because MH's have still their potential to explode violently due to other reasons then normal aging detectable electrcally - like undiscovered manufacturing defect in the quartz material structure.

The protection sense the lamp voltage and when it rise too much, or show other abnormal behavior (rectifying,...), the ballast shut down.
It is based on the fact, then both cycling and arctube explosion are preceded by severe arctube overheat, what yield to arc voltage rise due to increased pressure.
The overheat is caused by extra power dissipation in the lamp, namely light absorption of blackened arctube wall and increased cathode fall on worn out electrode. On MH this overheating accelerate the quartz aging, so beside the elevated pressure and temperature, it become less strong, so then explode.

On magnetic ballast (nearly constant current source in the operating range) this usually lead to fatal thermal runaway due to positive feedback: Increased temperature -> Increased pressure -> Increased arc voltage -> Increased arctube input power -> Further temperature increase -> and so on.
On electronic ballasts this feedback is interrupted (constant power regulation), or even suppressed (constant temperature). Beside of this, electronic ballast prolong the time, before the lamp reach such condition.

It is possible to sense such overheat (voltage) in the ignitor (the only component with possible intelligence in it in the magnetic ballast system), but there is no means to shut the burning arc in the faulty lamp down in the safe manner (shorting the lamp is not usable, as it might start ballast fire) and without introducing high power dissipation in normal operation (interrupting the lamp current by series triac switch - it would dissipate; Relay would be not much reliable, as the circuit is highly inductive). So ignitors limit their functionality to not restart the detected faulty lamp, after it extinguish by itself - good for solving HPS annoying cycling, but too late for MH explosion prevention.

the only real difference between these and magnetic ballasts is poor reliability.  Tough, you can't beat the energy savings of a non-functional fixture with a dead electronic ballast 

I second that, having just had yet another e-ballast fixture go 'kaput' I think the energy cost savings from a slightly more efficient ballast are totally wiped out by the cost of replacing the fixture every two years!

I completely agree that the energy savings are not worth the unreliability of most electronic ballasts. Besides the electric consumption, you have to consider the energy that is consumed by manufacturing these ballasts, transporting them, and installing them every few years when they fail. In addition, replacing the ballasts more often generates more waste. So, if you are faced with the argument of "going green" by saving electricity, point out the additional environmental impact of an unreliable product!

-Nelson

Well, magnetic ballasts have been officially banned up here in Canada according to here started two months ago. Most of the big box stores here have already stopped selling magnetic ballasts and sell only electronic ballasts now but some still have the old magnetic ballasts in stock but there being marked down/cleared out now. I guess that in around a year or so to only place to get a magnetic ballast is to find a NOS one at a store or to pull one out from a salvaged fixture.

As for the electronic ballasts I noticed that they tend to fail after a few years of operation, even faster for some if a dead lamp is left in for too long. I myself prefer a properly working magnetic as they seem to be more robust and durable. I also noticed at my local home centre that the older magnetic fixtures came with Advance/Universal ballasts but the newer electrnic ballasted fixtures came with Keystone or Accupro ballasts.

Electronic HID ballasts drive the lamp at low frequency (under 400Hz), but they also provide the same flicker-free operation of HF fluorescent ballast. 

The output stage is driven by a low-frequency inverter that drives the lamp in alternating squarewave, so, the drive-frequency modulation is almost non-existent in light output.  Same can not be said about sinewave line frequency driven ballasts. 

petitiononline is a good site for petition hosting. Someone needs to write up a professional and well thought out petition like I did for MV lamps and once we do I'll do what I can to sign it and spread the word.

I completely agree that the energy savings are not worth the unreliability of most electronic ballasts. Besides the electric consumption, you have to consider the energy that is consumed by manufacturing these ballasts, transporting them, and installing them every few years when they fail. In addition, replacing the ballasts more often generates more waste. So, if you are faced with the argument of "going green" by saving electricity, point out the additional environmental impact of an unreliable product!

-Nelson

Same applies with those hyped up "hybrid" cars.  They use less fuel, but they leave a HUGE environmental footprint because of those batteries with a finite life.  People would be better off buying equally as efficient diesels.  They last longer, so there is less waste too.
Same principal with magnetic ballasts.  They last longer so less end up in the trash.

This is to pave the way for the newer instant start electronic ballasts. If electronic ballasts are so much better then why is it necessary to ban magnetic ones? Let the market decide which ones are better. I personally like magnetic ballasts better because they last longer and lamps last longer because of the gentle startup cycle. And there's the awesome blinking of preheat start up and the awesome startup flicker of rapid starts. Tell the government to keep out of the lighting industry!

There will always be the lowest bid contractor cutting every corner possible.

These legislation mainly affect commercial users and instant start is just fine for their purpose since the lamps usually stay on at least 8 hours a day and seldom cycled. 

Energy accounts for over 80% of lighting cost in commercial world so cutting power usage is more important than having the ballast last decades.

NEMA Premium electronic T8 IS is 30% more efficient than an Advance Mark III F32T8 RS. 

Residential use ballasts with PF <0.9 are exempt.  Power factor correction isn't necessary for residential ballast and ballast factor(the output) is not dependent on power factor.

I'm not sure if they actually cause more maintenance.  For each lamp that goes out, two lamps go out in a series wired RS.  IS ballasts are parallel wired, so the only lamp that goes out is the one that failed.  This can lengthen the group-relamp interval and reduces the frequency of spot re-lamping even though there maybe more ballast failures, but major manufacturers warrant the ballast for 5 years and some include free service calls. 


SYLVANIA sends out its service crew and provide ballast replacement including labor for 5 years with its Quick60+ program.   

now i know why a local parts house dumped their stock of 175w mv lamps at $1 ea.
i bought a case of them as i maintain several yard lights.
i suspect there will be plenty of lamps and ballasts around for a long time.by the time they are extinct we wont care anymore.1000 lm/w led's will have become mainstream.