We would also like to see at least stiil photos of the ones that were used at the two coverter stations of the Pacific DC Intertie prior to their replacement by thyristors.
@oracle2world Actually, one of these did appear in at least one Frankenstein film. The company that made them had a demonstration rig which used to sit on their stand at the Electrical Engineering Exhibition back in the 50's/60's and this was used at least once in a film. The factory was quite near to Shepperton Studios and also Walton Studio.
Brilliant, I have not seen one of these working since I worked as an Electrician for London Country Buses / Green Line Coaches (formerly London Transport). Every garage used to have one of these (some had two) and they were used as as battery chargers. We could charge many batteries at the same time and could adjust the output voltage and current independently .
When we used to have have groups of school children visit the garage, I use to fire it up. It is now in the LT Depot Museum in Acton.
they do definitely look like alien brains. love em. I also love the comment at the top about using a transformer in place of a rectifier 8P enhanced by the fact they both rely on or perform polar (tee hee hee) opposite tasks.
I wonder if there are any other Mercury Arc Rectifiers in any other UK rail substations? Perhaps on the Southern Region? I believe rotary converters were in use at some substations on the Southern.
a Mercury Arc Produces alot of UV Radiation...so i imagine it might be bad for your eyes to be staring at that thing directly for an extended period of time.
@joeylawn36111 The Glass Does indeed Block Most of the UV Rays...but Enough of it Still gets through that Prolonged exposure would cause some irritation to the Eyes and maybe to the skin.....
well. AC is altenating current that simply moves back and forth. You are acutally using it right now and all other stuff in your house does use AC and you know that because it will make a buzzing sound if you hear correctly. But for DC this current moves only in one direction just like in batteries thats why they put on DC as a sticker on the side
xXxmidgexXx nailed it. They had to use these big things mainly for subways because smaller, less dramatic alternatives just can't (or couldn't) put out enough voltage to be useful for that type of thing.
Small follow-up having read other comments. Yes, this does give off UV, but any lightning storm coming by is giving you a much higher dose. Also, do not trust anything you see in Wikipedia about tubes. Articles written for Wikipedia by Tube Collector Association members - a Yahoo group of Ham experts, engineers, etc. have all been mangled by those who know very little and think highly of displying that to the world.
I can't speak to the efficiency question, but these tubes were not hooked up to vacuum pumps, so emissions from pumps was a non-issue. They are permanently sealed units just like all vacuum tubes, mine is 90 years old and functions just fine. However breaking one releases about 1 pound of mercury.
Hi all. For information, I would like to add that the larger MAR's (500A +) did/do have vacuum pumps to counteract the small losses associated with seals (which the smaller MAR's do not have).
Ive heard that these are no longer used because they are not as efficient as their newer solid-state (SCR?) counterparts, and because the vacuum pumps necessary to keep the inside of the bulb airtight continually released mercury vapour into the air.
Ive just seen one of these still operating today at MOTAT, Auckland , NZ . I was watching it with fascination , and arc up real bright when the trams where running . Ive never seen one before today , Now im finding out as much as possible .
Its like something outa flash gordon , bloody awesome. go there , see it working ..
right but a transformer on a small appliance (such as a cordless phone base, cell phone charger, etc) have diodes in them to switch to AC after the voltage is stepped down.
Those sparkly dots moving around at the bottom are the arcs from the multiple (six, in this case) electrodes, moving around atop the mercury pool. And to think these things were once in fairly common use. I really want to see one on display in a museum, running, inside a big glass case in a dimly-lit room.
VERY spooky. This is scary and beautiful. I've seen these before, but never in operation - this is amazing. They're big and contain a huge pool of mercury. And yeah, if you laid your weiner on this, I'm not sure what would get it first - burns or electric shock.
What is the physical size of it? I also wonder why those constant arcs don't heat it up to the point of failure? It does not look like there is any cooling system.
Iv worked with a couple of those devices in other countries and they are still in use and still work very well but they do create a strong EMF field when there started up or theres a Surge in the Phase connecting line, and which can damage components near it.
The reason why a Mercury Arc Rectifier uses a Pool of Mercury on the bottom is because mercury Only passes Electricity one way as like Direct Current Goes one way so It changes AC to DC buy passing the current between to anodes, and the anodes sit in the pool of mercury on the bottom.
Well if you worked on it you still sound like you dont know what you're talking about. Current doesnt flow *between* the two anodes. Its set up as a pair of common cathode diodes with the anodes as the input and cathode as the output. Mercury conducts in both directions, but the carbon anodes cannot emmit electrons and so rectifying action occurs as electrons can only flow from the mercury pool cathode to the anodes. I think it may be you who is drunk. :-)
Mercury-arc rectifiers until recently were the primary means of converting very large amounts of AC power into DC because they could work with large amounts of power that solid-state rectifiers couldn't even begin to handle.
There used to be working in The Science Museum in London. Fascinating to watch. I believe it has now been replaced by a full wave solid state rectifier. Very nostalgic video. Thanks.
It converts AC (Alternating Current) electricity into DC (Direct Current) electricity. Since the 1960s diodes have been used to do this in much smaller installations....
My Father used to talk about these, he used to work with radar and klystrons, I guess they need a lot of DC power. I've never seen one in action, until now. Looks like something out of a 50s sci-fi flick.
They have one of these in Auckland, New Zealand. It is live and powers a tramline for excursions at the MOTAT (Museum Of Transport And Technology) in Western Springs. Used to enchant me as a child, and still does to this day :)
Send me a message and I can get around to grabbing a video of it if you wish.
Turns AC (alternating current) into DC (direct current) at very high voltages (125,000V)
A description of AC from wikipedia:
"An alternating current (AC) is an electrical current whose magnitude and direction vary cyclically, as opposed to direct current, whose direction remains constant. The usual waveform of an AC power circuit is a sine wave, as this results in the most efficient transmission of energy."
We would also like to see at least stiil photos of the ones that were used at the two coverter stations of the Pacific DC Intertie prior to their replacement by thyristors.
rsp196607 2 months ago
ABB
rsp196607 2 months ago
Asea Brown Boveri
avenged06x 4 months ago
@oracle2world Actually, one of these did appear in at least one Frankenstein film. The company that made them had a demonstration rig which used to sit on their stand at the Electrical Engineering Exhibition back in the 50's/60's and this was used at least once in a film. The factory was quite near to Shepperton Studios and also Walton Studio.
ericperic66 5 months ago
How much power is that thing dissipating?
rsp196607 7 months ago
How come these never appeared in Frankenstein films and the such? Great audio and video presentation. I mean, if you want a mad scientist ambience.
oracle2world 8 months ago
Brilliant, I have not seen one of these working since I worked as an Electrician for London Country Buses / Green Line Coaches (formerly London Transport). Every garage used to have one of these (some had two) and they were used as as battery chargers. We could charge many batteries at the same time and could adjust the output voltage and current independently .
When we used to have have groups of school children visit the garage, I use to fire it up. It is now in the LT Depot Museum in Acton.
fartingvicar 8 months ago
I still have 6 of these in service. 700 KW each. Made by Brown Boveri in 1964 powering the DC engines of a steel rolling mill.
DutchFord86 1 year ago
talk about out dated technology...its old school
Amoorsable 1 year ago
very interesting video and great info, thanks for uploading.
dhymers 1 year ago
they do definitely look like alien brains. love em. I also love the comment at the top about using a transformer in place of a rectifier 8P enhanced by the fact they both rely on or perform polar (tee hee hee) opposite tasks.
lexichronicle 1 year ago
I wonder if there are any other Mercury Arc Rectifiers in any other UK rail substations? Perhaps on the Southern Region? I believe rotary converters were in use at some substations on the Southern.
G0IMB 2 years ago
I Want it for my collection,... Shame, they are rare..
Sergi762 2 years ago
lol
matgoro26 2 years ago
a Mercury Arc Produces alot of UV Radiation...so i imagine it might be bad for your eyes to be staring at that thing directly for an extended period of time.
form109 2 years ago 4
Glass blocks most of the UV rays.
joeylawn36111 2 years ago
@joeylawn36111 The Glass Does indeed Block Most of the UV Rays...but Enough of it Still gets through that Prolonged exposure would cause some irritation to the Eyes and maybe to the skin.....
form109 2 years ago
I can listen to that thing buzz allday lol xD
xXxmidgexXx 2 years ago 2
i know im an idiot but...what's that thing? what does it do?
Hallucination01 2 years ago
These things basically invert AC into DC for the trams operating from them
xXxmidgexXx 2 years ago 2
Comment removed
Hallucination01 2 years ago
well. AC is altenating current that simply moves back and forth. You are acutally using it right now and all other stuff in your house does use AC and you know that because it will make a buzzing sound if you hear correctly. But for DC this current moves only in one direction just like in batteries thats why they put on DC as a sticker on the side
xXxmidgexXx 2 years ago 2
oh...cool...:D...thnx..i know it now xD
Hallucination01 2 years ago
xXxmidgexXx nailed it. They had to use these big things mainly for subways because smaller, less dramatic alternatives just can't (or couldn't) put out enough voltage to be useful for that type of thing.
12stmushroom 2 years ago 2
current*
NutsandGuts 2 years ago
Comment removed
12stmushroom 2 years ago
how much mercury is in that thing?
form109 3 years ago
Enough to make fillings for all of New York's hobos.
jizzmonger 3 years ago 7
It looks like an alien brain calculating how much is 1+1.
peterban1234 3 years ago 10
trippy...
azngangstr0 3 years ago
Its so Beautiful!!!
Inuyasha44320 3 years ago
Small follow-up having read other comments. Yes, this does give off UV, but any lightning storm coming by is giving you a much higher dose. Also, do not trust anything you see in Wikipedia about tubes. Articles written for Wikipedia by Tube Collector Association members - a Yahoo group of Ham experts, engineers, etc. have all been mangled by those who know very little and think highly of displying that to the world.
SudoNimh 3 years ago 3
I can't speak to the efficiency question, but these tubes were not hooked up to vacuum pumps, so emissions from pumps was a non-issue. They are permanently sealed units just like all vacuum tubes, mine is 90 years old and functions just fine. However breaking one releases about 1 pound of mercury.
SudoNimh 3 years ago 4
Hi all. For information, I would like to add that the larger MAR's (500A +) did/do have vacuum pumps to counteract the small losses associated with seals (which the smaller MAR's do not have).
mowerofdoom 3 years ago
Ive heard that these are no longer used because they are not as efficient as their newer solid-state (SCR?) counterparts, and because the vacuum pumps necessary to keep the inside of the bulb airtight continually released mercury vapour into the air.
Sushi4breakfast 3 years ago
Ive just seen one of these still operating today at MOTAT, Auckland , NZ . I was watching it with fascination , and arc up real bright when the trams where running . Ive never seen one before today , Now im finding out as much as possible .
Its like something outa flash gordon , bloody awesome. go there , see it working ..
ricardorocker 3 years ago
Don't mercury arcs give off UV rays?
BenHutchinson1 3 years ago
Are these what change AC power to DC?
Pommit 4 years ago
Yes, that what rectifiers do.
soundseeker63 4 years ago
you can also use a transformer, this is just one of the things that do it
genesis1357 2 years ago
No, a transformer changes the voltage. A rectifier changes AC to DC.
bodnet 2 years ago
right but a transformer on a small appliance (such as a cordless phone base, cell phone charger, etc) have diodes in them to switch to AC after the voltage is stepped down.
genesis1357 2 years ago
@genesis1357 The more accurate term would be power supply since the transformer and rectifier combine to make up the power supply.
lasdlt 2 years ago
Those sparkly dots moving around at the bottom are the arcs from the multiple (six, in this case) electrodes, moving around atop the mercury pool. And to think these things were once in fairly common use. I really want to see one on display in a museum, running, inside a big glass case in a dimly-lit room.
JonasClark 4 years ago
VERY spooky. This is scary and beautiful. I've seen these before, but never in operation - this is amazing. They're big and contain a huge pool of mercury. And yeah, if you laid your weiner on this, I'm not sure what would get it first - burns or electric shock.
JonasClark 4 years ago
In his case he would end up with a Li'l Smokie.
jizzmonger 3 years ago
So if i laid my weiner on that would it hurt?
heresyournametagmark 4 years ago 6
looks like an uber-trippy bong
Playbenny 4 years ago 6
Looks like Casper the ghost!
jigsaw1984 4 years ago
why need a fan.
xXxmidgexXx 4 years ago
prolly in case any mercury vapor escapes. you wouldn't want it lingering around.
genesis1357 2 years ago
Beautiful / wicked cool
augsteyr 4 years ago
Now that you pointed it out, I do see the fan. Thanks for posting that.
scarecrow7771w 4 years ago
What is the physical size of it? I also wonder why those constant arcs don't heat it up to the point of failure? It does not look like there is any cooling system.
scarecrow7771w 4 years ago
If you look at the distance shot again, you can see a fan underneath it, so it is being cooled. I don't know how big it is though...
tapewolf 4 years ago
About 15 inches tall, quite big, and spooky when at first you don't realize what it is
Downmaster 4 years ago
tried to buy one on ebay no success could stare at it for hours and get a nice tan to boot don't think my wife would like it in the lounge!.
ballores 4 years ago
Gives off much X-rays and UV radiation.
Rohmell 4 years ago
cool video. I work in a cinema and we hav a old mercury rectifier to change ac to dc for the lamp houses.
graeme4302 4 years ago
one word: wow!!!!!!!!!!
awsomehighvoltage 4 years ago
Iv worked with a couple of those devices in other countries and they are still in use and still work very well but they do create a strong EMF field when there started up or theres a Surge in the Phase connecting line, and which can damage components near it.
nineaclock 4 years ago
The reason why a Mercury Arc Rectifier uses a Pool of Mercury on the bottom is because mercury Only passes Electricity one way as like Direct Current Goes one way so It changes AC to DC buy passing the current between to anodes, and the anodes sit in the pool of mercury on the bottom.
nineaclock 4 years ago
Thats totally incorrect. See wikipedia 'Mercury arc valve'.
robotbugs 4 years ago
Ya, well Wikipedia are a bunch of drunks who put stuff up on how they THINK it works, take from an person that has worked on them before thanks :)
nineaclock 3 years ago
Well if you worked on it you still sound like you dont know what you're talking about. Current doesnt flow *between* the two anodes. Its set up as a pair of common cathode diodes with the anodes as the input and cathode as the output. Mercury conducts in both directions, but the carbon anodes cannot emmit electrons and so rectifying action occurs as electrons can only flow from the mercury pool cathode to the anodes. I think it may be you who is drunk. :-)
robotbugs 3 years ago 4
Now that is some great information to check out, thank you for the post.
Dishfarm 4 years ago
I checked it out on wikipedia, very interresting information.
Dishfarm 4 years ago
Mercury-arc rectifiers until recently were the primary means of converting very large amounts of AC power into DC because they could work with large amounts of power that solid-state rectifiers couldn't even begin to handle.
douro20 4 years ago 3
lmao, it looks diabolical :)
Z0DI4C 4 years ago 3
There used to be working in The Science Museum in London. Fascinating to watch. I believe it has now been replaced by a full wave solid state rectifier. Very nostalgic video. Thanks.
102trafalgar 4 years ago
? what is its purpose ? reply me .
thexrealxASK1 4 years ago
It converts AC (Alternating Current) electricity into DC (Direct Current) electricity. Since the 1960s diodes have been used to do this in much smaller installations....
bodnet 4 years ago
How does it work I didnt no that it converted ac to dc but inew that they didnt have diodes back them then thanks for the video!
Atomic101Heli 4 years ago
@bodnet It does not convert DC into AC; it converts good into evil. Only the devil himself could design something so beautiful.
SteveTheCart 1 year ago
My Father used to talk about these, he used to work with radar and klystrons, I guess they need a lot of DC power. I've never seen one in action, until now. Looks like something out of a 50s sci-fi flick.
cpmisalive 4 years ago
They have one of these in Auckland, New Zealand. It is live and powers a tramline for excursions at the MOTAT (Museum Of Transport And Technology) in Western Springs. Used to enchant me as a child, and still does to this day :)
Send me a message and I can get around to grabbing a video of it if you wish.
N4CR5 4 years ago
What exactly does a mercury arc rectifier do?
EnkiduPDX 4 years ago
Turns AC (alternating current) into DC (direct current) at very high voltages (125,000V)
A description of AC from wikipedia:
"An alternating current (AC) is an electrical current whose magnitude and direction vary cyclically, as opposed to direct current, whose direction remains constant. The usual waveform of an AC power circuit is a sine wave, as this results in the most efficient transmission of energy."
cpmisalive 4 years ago
Fasinating! Wat is the vintage of the device? What are the operating parameters -- V , A?
burali7 4 years ago
As far as I can tell - it was installed in 1935, is rated at 200kW, and operates at 550V. Video information text now updated with more stuff!
bodnet 4 years ago
Use to see these when my dad use to take me to work with him (British Telecom engineer) back in the mid 80's
BT was Refitting exchanges with Solid-State at the time meant the doom for Mercury arc valves used in the big exchanges.
Impressive to see them working in person.
hitechguy18 4 years ago
cute
WDX7770243546 4 years ago
that is the coolest sound.
thewelderdude 4 years ago
ditto, seeing one live is quite cool.
lukosrage 4 years ago
Impressive... I've also seen it only in books.
rawiinyo 4 years ago
Tx for posting this.
Aeryk333 4 years ago
I've only seen pictures of this before. It's very cool to see one "live"
JonFinnerud 4 years ago