Saw these on eBay.
http://www.ebay.com/itm/200602992870
They say 50 Hz. If so, why were they imported to the US with an incompatible ballast? Another auction has some that clearly have GE US markings on.

Are they foreign-made lights? The construction looks pretty American to me. It's possible they were made in the US for export use but never exported.

Are they foreign-made lights? The construction looks pretty American to me. It's possible they were made in the US for export use but never exported.

Probably true, but i have never seen anything like that.
Is it 220/240 volt? If not, it would likely work on 60Hz.

It will work with 60 Hz, but if supplied with 240V, it will underdrive the lamp at somewhere under 5/6ths (50/60) of its rated power

The math is, the ballast impedance for 60 Hz is 6/5 times the impedance for 50 Hz, but the lower current means lower pressure for the HPS lamp, so lower arc voltage - Then the power will be lower than 5/6ths. Dont know by how much exactly, i think it will be about 100W..110W

You can overcome this if you step up the input voltage. 277V would likely be pretty close for proper working. But remove the PFC capacitor



Other question is, where you get the S56 HPS lamp. That is the standard (and only) 150W HPS lamp used in the 240V/50Hz hemisphere, but i understand it is not common in the US

A 150W Pulse MH may be a good substitute

You can still get the S56 lamps. See here.

Well, in the other half of the world this is the standard 150W HPS lamp, so obviously no problem getting it from an international website. I was thinking locally when i asked

That is a US website, but I don't think S56 lamps are available in most stores here.

1000bulbs.com has them.  I had to get one a few years ago as a replacement for the still working Westy lamp that came with a General Electric floodlight.

The S56 westy can be found on ebay for 10 bucks.
  I have a costar Westy  S56 lamp with a clear arc tube.

Also the other day i saw GE 250  230 volt 50Hz heyhibay units.  Prolly only reason is that we have a older 240 volt 3 phase delta system in the US.

Quote from: nicksfans on December 17, 2015, 01:17:53 AM

Are they foreign-made lights? The construction looks pretty American to me. It's possible they were made in the US for export use but never exported.

Probably true, but i have never seen anything like that.
Is it 220/240 volt? If not, it would likely work on 60Hz.

The ballast looks like just a single choke reactor (with tap for ignitor), HX ballast needs two windings, separated by magnetic shunts, I do not see anything like this here.
And because the S56 needs at least 200V OCV, the series choke means at least 200V mains.

And even if it is 120V/50Hz, it may well be intended for some region, where this is still in use (at least till recently the 120V/50Hz was quite frequent here...).

By the way isn't the 50Hz mains common in Mexico or South America (quite plausible "target" for an US made fixture)?

Medved did your part of the world have 127/220 volt supply's I know Russia had it in places I'm curious power supply's in other country's always fascinated me

Medved did your part of the world have 127/220 volt supply's I know Russia had it in places I'm curious power supply's in other country's always fascinated me

The old pre-WW2 installation was 120V/50Hz, it was between phases of a 3-phase system. The "Neutral" was grounded at the distribution transformer, but not used to connect any load. The system then used 2 fuses for single phase home connection. Originally it haven't used the PE wire, it had relied on the 70V phase to Ground voltage to be low enough to be considered as "still safe" in the early 20'th century, when this system was born.

After WW2 this system was getting gradually replaced by the 3x220/380V, which later became the present 3x230/400V with Neutral grounded and used for single phase loads.

Still around 2000 few places at least in Prague and maybe even Brno (old housing) had still the 120V in use, how that evolved till today I do not know. Very likely it was already replaced by the 3x230/400 or just diminished, as the old houses were either torn down or completely overhauled.

I would guess it is similar story as with few DC delivery points in the US - as far as I noticed, around 2000 these customers (as far as I know just power connections for some high speed elevator machinery in older skyscrapers were connected to DC) were switched to AC delivery, with the rectifier becoming property of the customer.

Interesting I never knew there was a 70/120 volts system its amazing how many different odd voltages there were. Here in Weymouth  we originally had 230/460 DC as well as 230/400 later uprated to 240/415 which is still what we have now. the DC system was switched off in 1966 a year before I was born

The "3x240V" in the system designation indicates the single phase loads are supposed to be connected between the phase and Neutral.
But the 70V between the phase and ground was never used to power anything, all loads were always connected across the 120V between two phase wires (after all there was no Neutral wire or so, just the three phase wires).
So the correct designation is just "3 phase 120V" and not "3x70V/120V".

It is interesting there were DC mains systems with as high as 230V or so (I expect the "460V" was just 2x230V around a common Neutral), I would seriously doubt their safety for domestic use (mainly arcing problems - switches, failing lamps, fuses,...), I'm quite surprised these were dismantled as late as in 60's...

There were a a lot of DC and non standard AC system in use in the UK. City's like London had more than 20 power company's all giving there own different voltage and frequency in some areas there was 250/500 volt DC the lowevoltage for lamps and small loads the higher voltage for commercial/industrial loads such as motors etc. If you look at vintage UK radios and TVs you will see a voltage adjuster market usually 200 220 230 240 250 volts to cater for all that was available. Although 50c/s was common there was 40 60 83 and 100 c/s too! Oh and also 25c/s