Control Gear for Osram Endura

Topics relating to lighting control gear, including magnetic & high frequency ballast and ancilliary devices such as starters, ignitors and switchgear.
User avatar
Globe Collector
Posts: 73
Joined: Tue Apr 24, 2012 12:37 pm
Favourite Manufacturer: General Electric Company of England
Area of interest: High Intensity Discharge Lamps_ Lamp Chemistry_Spe
Location: Hobart, Tasmania

Control Gear for Osram Endura

Postby Globe Collector » Mon May 28, 2012 7:15 am

Hello Everybody,
Went to Melbourne last week and managed to pick up some Osram Endura control gear, but unfortunately, no lamps as yet.
I procured enough units to strip some and extract the circuit. They consist of a two stage R.F.I. filter, followed by a bridge rectifier and a 470nF H.F. bypass cap. The next stage is a continuous-mode, boost architecture, crest factor corrector based around ST's L6561 chip and an Infeion 11C60S5, 600v, 11A M.O.S.F.E.T. The filter capacitors are two 150uF 250v units in series with discharge resistors. At the cold end there is a 1 watt, 100 ohm resistor to limit the inrush. When the boost converter starts, rectified A.C. from an overwind on the boost inductor switches on a Fairchild 12N60C3, 600v, 24A I.G.B.T. to short out the resistor.
All this guf drives the oscillator, a totem-pole, steering transformer driven design using two more 12N60C3s. The design is
very similar to that used in a myriad of cheap GLS lamps and alike, to reduce power consumption. A range of fittings followed which only took compact fluorescent lamps, which could be fitted where historically tungsten lamps would have been used as the source. For example, PL downlighters.">Compact Fluorescent Lamp impedance converters. The output, taken from the node between the two stacked 12N60C3s is coupled by a 150nF film cap (to block the D.C. component) directly to the choke, a ferrite cored, litz wire wound affair. After this there is a series resonant cap to deck of 3n3 at 2Kv, one of those red European WIMA things. The lamp driving primary windings are connected in parallel with this cap. Two, series connected ceramic capacitors of 220pF and 1nF connect the output back to the primary of the steering transformer driving the gates of the two 12N60C3s to complete the feedback loop.
Like in a compact fluoro, the oscillator is started by a diac connected to the gate of the lower 12N60C3. P.N.P. transistors fitted between the steering transformer secondries and 12C60C3 gates chop off the negative going excursions from the secondries.
An SCR, also hanging from the gate of the lower 12C60C3 to deck is triggered if the lamp is broken or removed and the series LC circuit on the output approaches resonance. (Note that a series LC circuit at resonance is a dead short and the voltage on the node between the L and C becomes excessively great, the loading of the lamp across the C element maintains a low "Q" and prevents it running away). Some of the H.F. from the output terminal is "sniffed" off between the two series connected ceramic caps in the feedback path and clipped by two series, back-to-back 33v zeners loading a 470 ohm resistor. The voltage across this 470 ohm resistor is capacitively coupled to a "radio-ham's" rectifier (one inverse diode to deck, one foward diode out to the load), by a 1nF ceramic cap. This is fed through 500K of resistors to charge up 1.2uF of capacitors. The voltage on these caps triggers a second diac, (20v) going into the gate of the SCR, so the response of the SCR is quite slow.
A 1 megohm resistor extends from the cold end of the 150nF output coupling capacitor up to the 350v D.C. rail. The small D.C. current from this goes straight through the litz choke and the lamp primaries maintaining no DC component at the output. The gate of another MOSFET, a small 1A drain current one, is coupled to this same node by 500K of series resistance and another "ham" rectifier, but not capacitively coupled. Two 1n2 capacitors, before and after the "ham" rectifier act as hash filters. The square wave output is rectified by this "ham" rectifier and turns the MOSFET on, its drain is connected to the oscillator starting diac and its RC circuit, discharging C and preventing the diac firing after the oscillator starts. If the lamp is removed the windings driving it go open circuit and the current from the 1Meg resistor is now free to keep that MOSFET on, preventing the oscillator from being started after the SCR has killed it.
Considering that the Endura lamp itself is designed to run fo between 5 and 800,000 hours, seeing this gear is an eye-opener as to an electrical engineer's challenge to design a circuit to last this long. The inrush 100 ohm being shorted by an IGBT is novel and reduces stress on all upwind components exposed to this surge. The bridge rectifier diodes are quite solid for a 150 watt unit and a single 275v varistor has been retrofitted under one of the line filter bucking inductors. Thw oscillator transistors are really solid overkill, 600v Vcgo, 24A collector current, when compared to the MJE13007s often seen in larger compact fluoros, (3A, 500v). All the housekeeping stuff, extra small MOSFET and SCR, is something that would definitely mot be considered in a compact fluoro.
The thing did have a weakness though, the RoHS, lead-free solder used. This stuff is almost pure Tin, with a little copper dissolved in it. It was noticeably "crystalline", sort of in the way molten Bismuth freezes. In the centres of vias one could see the crystal grains and flexing the board bought fourth a lit of little "creaks and squeaks" so common of metals like indium, tin and bismuth. I swear this is why it had failed, something had come adrift when the solder cracked! Note that tin has two common allotropes, white, or metallic tin, stable above 16.5*C, and grey tin, a grey, less metallic form which slowly forms if tin is kept at below 16.5*C.
I have seen shots taken in Mawson's Hut, in Antarctica. The food cans are still stacked there 70 years later, but they are all grey and dusty looking from the tin plating being so cold for so long! I'm sure the small copper content alters this process, bit the RoHS solder has a long way to go before it attains the reliability of the old 60-40, Tin-Lead eutectic grade.
I have taken photos, created the circuit and written a prasie of how it works, so can somome tell me how to upload them so everybody can see, in detail, how it works.
I have also got some electronic gear to run a HQI-TS 70W, but I have not drawn its circuit yet.
Andrew


P.S. Anyone want to see photographs, at close range of an XBO-4000 (200A D.C. at 20v arc drop), super high pressure xenon lamp in operation!?

User avatar
MetalHalideHater
Posts: 162
Joined: Sat Jul 02, 2011 6:31 pm
Contact:

Re: Control Gear for Osram Endura

Postby MetalHalideHater » Mon May 28, 2012 7:33 am

Fantastic explanation. Yes, I would love to see a close up of Xenon in operation.

User avatar
Globe Collector
Posts: 73
Joined: Tue Apr 24, 2012 12:37 pm
Favourite Manufacturer: General Electric Company of England
Area of interest: High Intensity Discharge Lamps_ Lamp Chemistry_Spe
Location: Hobart, Tasmania

Re: Control Gear for Osram Endura

Postby Globe Collector » Tue May 29, 2012 4:06 am

Tried to upload the Xenon and Endura Gear Circuit images, came up with error message, "A valid form token could not be found", does anyone know what this means? Its far to cryptic for me to work out.

User avatar
Globe Collector
Posts: 73
Joined: Tue Apr 24, 2012 12:37 pm
Favourite Manufacturer: General Electric Company of England
Area of interest: High Intensity Discharge Lamps_ Lamp Chemistry_Spe
Location: Hobart, Tasmania

Re: Control Gear for Osram Endura

Postby Globe Collector » Tue May 29, 2012 5:10 am

I know its a little off topic, but finally got the xenon to go up, now I'm going to try and attach it to this post, if it works, I'll get back to the Endura Circuit.Image

O.K. cant get the image tags to work, but the image has been placed in the gallery, under "other types of discharge lamps" at
http://allthingslighting.co.uk/atl/displayimage.php?pid=8011;

Kev somehow attached an image of stuffed H.F. gear to one of his posts, but I can't find out how he did it, and without the ability to pick the code of his post to bits, i.e. use the "edit" function to look at the code of someone else's post to see how they did it. I won't post the image of the Endura Circuit until I solve the problem of how to attach the image to the relevant post because to describe how a circuit works, one must have an immediate and ready reference to the relevant circuit image.

Thanks Colin and Close9, now everybody should be able to see it, it was a very impressive thing, even through two sheets of glass the U.V. content of the beam could be felt of one poked one's hand into it.

I have another shot of it, taken just 250ms after the arc was shut off and the anode was still incandescing at 1600 centigrade.
It took ages for the anode to cool. I kept photographing it as it cooled, it took the camera about 10 sec to recycle for the next shot, after 14 odd shots the anode was still at around 1000 centigrade. Goes to show what a crappy conductor a high atomic mass gas, such as xenon is, even at 30 odd atmospheres pressure. Ill tack the hot anode picture to a new post and then the endura gear circuits to further posts after that. Oh, B.T.W. I had said in a previous post about a month back that I have seen Endura gear at Osram with huge laser trimmed capacitors in it, considering I now have genuine Endura gear, the gear I saw must have been for much larger lamps, maybe even the HQI-T 2000s at the M.C.G.
Attachments
CSX_4000_Operating_02.jpg
CSX 4000 Equivalent operating at St. Kilda Film Festeval, Melbourne, Australia, 22nd May, 2012
Last edited by Globe Collector on Thu Jun 07, 2012 7:53 am, edited 3 times in total.

User avatar
sailormoon01uk
Posts: 315
Joined: Wed Feb 16, 2011 11:40 pm

Re: Control Gear for Osram Endura

Postby sailormoon01uk » Tue May 29, 2012 6:58 am

You need to add the photo as a attachment, by scrolling down and then click on Upload Attachment Click in the Browse Button, add your photo, then typr in the details in the File Comment box then Click on Add the File button, once all don and you have typed your message Clock on Submit

I have attached a Photo of my Degassed Osram 2000w XBO Xenon DIscharge Lamp, as was used for Cimema Projectors and Nightsun Searchlights on Police Helicopters.

Hope this helps

All the Best

Colin
Attachments
Osram-2kw-XBO-Lamp.jpg
Degassed Osram 2000w XBO Xenon Discharge Lamp

User avatar
Paul
ATL Admin
Posts: 1303
Joined: Sun Jan 02, 2011 7:19 pm
Favourite Manufacturer: Thorn
Area of interest: Fluorescent battens and Thorn Vintage
Oldest item: 1890's Carbon Lamp
Location: Oxfordshire
Contact:

Re: Control Gear for Osram Endura

Postby Paul » Tue May 29, 2012 8:23 am

Valid form token usually means that the security token for your session has expired before you completed the process. It's to prevent man-in-the middle attacks.

User avatar
Globe Collector
Posts: 73
Joined: Tue Apr 24, 2012 12:37 pm
Favourite Manufacturer: General Electric Company of England
Area of interest: High Intensity Discharge Lamps_ Lamp Chemistry_Spe
Location: Hobart, Tasmania

Re: Control Gear for Osram Endura

Postby Globe Collector » Tue May 29, 2012 1:48 pm

Here's the one of the same lamp as above 250ms after shutoff.... (I had to turn it on its side so the blog site would accept it!)
Attachments
CSX_4000_Just_Shut_Off_02R.jpg
Anode of CSX 4000 Equivalent incandescing at 1600*C, 250ms after the arc was shut off.

User avatar
Globe Collector
Posts: 73
Joined: Tue Apr 24, 2012 12:37 pm
Favourite Manufacturer: General Electric Company of England
Area of interest: High Intensity Discharge Lamps_ Lamp Chemistry_Spe
Location: Hobart, Tasmania

Re: Control Gear for Osram Endura

Postby Globe Collector » Tue May 29, 2012 1:51 pm

O.K. back to the topic of impedance converters, specifically the one for the Osram Endura 150w. Here's the circuit for the line filter, rectifier and crest factor corrector half.....
Attachments
Endura-PSU1C1R.jpg
Osram Endura 150w Gear, Rectifier and CFC section

User avatar
Globe Collector
Posts: 73
Joined: Tue Apr 24, 2012 12:37 pm
Favourite Manufacturer: General Electric Company of England
Area of interest: High Intensity Discharge Lamps_ Lamp Chemistry_Spe
Location: Hobart, Tasmania

Re: Control Gear for Osram Endura

Postby Globe Collector » Tue May 29, 2012 1:56 pm

And here's the other, more interesting, oscillator half and the series resonant impedance match to the lamp!
Attachments
Endura-C1R.jpg
Osram Endura Gear, Oscillator and Impedance Match Half

User avatar
Globe Collector
Posts: 73
Joined: Tue Apr 24, 2012 12:37 pm
Favourite Manufacturer: General Electric Company of England
Area of interest: High Intensity Discharge Lamps_ Lamp Chemistry_Spe
Location: Hobart, Tasmania

Re: Control Gear for Osram Endura

Postby Globe Collector » Tue May 29, 2012 2:21 pm

Please use these in conjunction with the description at the top, It should all now be a lot clearer. I have photographs of the gear too, if you are interested I can post them too, with the major components labeled.
I have some other electronic gear here too, I think I have read one of Kev's posts referring to the specific brand, TRIDONIC-ATCO, made in Switzerland! I've never seen such gear before and did not even know that fully self-contained electronic gear existed for H.I.D. lamps, but reading your posts I realize it is quite common in the UK and big cities like Melbourne, down here in Hobart almost all streetlighting and shopping concourse lighting is controlled by magnetic gear, although I realize this will change.
I can see how much some of you dislike this electronic gear, and it is well known by engineers that the reliability of a circuit decreases as the number of components increase, (it should be intuitive anyway). I think that there is even an equation one can use to calculate the lifetime of a product based on component quality, heatsinking issues and circuit complexity. Great for those on the edge of honesty who want to engineer a product which dies just outside the warrenty period! Why, because they have an equation to calculate it !!!!! Here at the University of Tasmania, I know that the electrical engineering department offer a subject as part of the undergraduate degree on this exact topic, maybe I can go and be a "fly on the wall" at the back of the lecture theatre !
As an electronics technician, however, we have a saying,...."Why use a complex solution to a problem, when a simple one will do better!"
So, does anybody want to see the circuit of this Tridonic Atco 70w Metal Halide gear after I have extracted it? Holler here if you do !!

User avatar
Danny
Posts: 829
Joined: Thu Apr 21, 2011 10:24 pm
Favourite Manufacturer: GEC
Area of interest: Street lights fluorescent discharge
Oldest item: 120v 60w carbon lamp 1905
Location: North east england

Re: Control Gear for Osram Endura

Postby Danny » Tue May 29, 2012 2:56 pm

Blimey its going to take me ages to read this topic as some of the comments are that long i keep losing where I'm at!! :-?.
Last edited by Danny on Wed May 30, 2012 5:53 pm, edited 1 time in total.

User avatar
Kev
Posts: 1184
Joined: Wed Jan 05, 2011 10:32 pm
Favourite Manufacturer: Atlas and CourtneyPope
Area of interest: Discharge and Fluorescent
Location: Cornwall
Contact:

Re: Control Gear for Osram Endura

Postby Kev » Tue May 29, 2012 4:53 pm

Personally i think the tridonic Atco Electronic ballasts are crap. When they fail i rip them out and replace with magnetic!

User avatar
Globe Collector
Posts: 73
Joined: Tue Apr 24, 2012 12:37 pm
Favourite Manufacturer: General Electric Company of England
Area of interest: High Intensity Discharge Lamps_ Lamp Chemistry_Spe
Location: Hobart, Tasmania

Re: Control Gear for Osram Endura

Postby Globe Collector » Thu Jun 07, 2012 3:52 am

Nobody has made much comment about the Endura Gear so I'll now post the circuit of the Tridonic-Atco HQI-TS 70w electronic gear.
Now I know how much Kev hates this type of gear, and from his viewpoint of having to change and maintain thousands of them, I would too. But knowing thy enemy is part way to defeating thy enemy I say! I'd rather the doctor who knows smallpox treating me for smallpox than the doctor who does not even know it is a viral disease and pouring anti-biotics into me in vain!!
Half of this circuit is very similar to the Endura circuit, a Boost Architecture Crest Factor Controller. If you carefully compare to the Endura circuit you will see that, despite the type numbers and brands being different, (Semiconductor Technology, L6561 in the Endura and Fujitsu Electric PK0AN FAN7527 in this circuit), the pin outs are identical and the circuit around it is almost the same bar a few changed values of resistors. I would go so far as to say that the crest factor control chips are essentially the same device in each circuit. The way it initially starts though is different. In this circuit the lamp oscillator starts first followed by the crest factor corrector part whereas in the Endura it was the other way round.
The resevior capacitor in this circuit is a lot smaller, one fifth the capacitance and does not use the inrush control resistor shorted later by an IGBT, it is simply connected directly across the D.C. line.
The interesting bit is the "Oscillator". It is much more complex than in the Endura circuit. Whereas the Endura circuit uses a few descrete active semiconductors, a couple of IGBT's, a MOSFET, and SCR and a few diodes, this circuit has a full bridge architecture with each half of the bridge driven by a seperate and different high-side low-side driver chips.
All four bridge MOSFETS are driven by a dedicated oscillator, driver, monitor-control chip, the CM3593 which I could find no data on.
Like the Endura however, the lamp impedance match, (chokes, transformers and capacitors) around the lamp seem to again rely on series resonance at least to some extent. The main lamp choke is wound with about 50 turns of 1mm Litz wire, and looks similar, but smaller to the main Endura Choke. The starting transformer, the tapped coil at the top end of the lamp, is wound with ordinary enameled transformer wire and is quite a lot thinner than the Litz on the main choke and seems to have about 100 turns in all, 50 on each half. The ferrite core is twice as deep as the choke's core. One would expect that the inductance of the half of this inductor permanently in series with the lamp to have much greater inductance than the main choke itself at the operating frequency, unless the other half is somehow shorted out (thus effectively shorting the lamp series half by transformer action) during operation.
The half bridge high-side low-side driver chips are interesting too, firstly because they are different. Engineers are creatures of habit, and if they cotton-on to a circuit structure which needs to be used more than once in a design, they usually duplicate it rather than re-design the wheel again. In this circuit one side of the bridge is driven by a Semiconductor Technology Brand L6385, (in the same family of power control chips as the L6561 used in the Endura), whilst the other side is driven by an International Rectifier brand IR2101S. Both chips perform a similar function, viz taking two complimentary logic level ground referenced drive signals, dropping the source impedances of both to drive the gate capacitances of the MOSFET's and "lifting" one signal up referenced to the high voltage square wave node between the two MOSFET's to drive the upper MOSFET. This second function, from an electronics point of view is a marvellous "holy grail" function because the upper drive is translated up by 450 odd volts inside the chip. Thus this chip contains high voltage epitaxial devices, which up until recently, were not intergatable into a chip. Actually, up until quite recently, no chip could withstand a Vcc-Vee voltage greater than about 80v. These chips demonstrate that this limiting ceiling has been broken and greater functionality is now available at much higher voltages and energy levels, ultimately making gear like this possible.
The question still remains though, why did the designer use two different driver chips for the left and right sides of the bridge? Also, all four MOSFET's possess seperate control lines back to the control chip. In a simple full bridge diagonally opposite devices (MOSFETS's) are switched alternately to simply reverse the polarity of the load. Sometimes one corner is Pulse-Width-Modulated whilst the diagonally opposite corner remains on, a filter on the output then knocks off all the HF PWM leaving a nice sine wave. But that is not what is going on here.
I summise that one half of the bridge switches all the time to keep the lamp going and the other half is switched only during start-up to get the lamp ingited. I summise that the control chip possibly contains a programmable logic array or eeprom, programmed with the arc characteristics of the lamp and other features like starting pulse duration and repetition and end of life detection. In this sense this circuit is much more complex than that of the Endura. I also summise that the control chip, which is "watching" just about everything via resistive potential dividers, alters the frequency somewhat to adjust the lamp current and arc voltage as the lamp ages. It may well detect end of viable lamp life too. It would be interesting to see if thy make one with a photosensitive device which "watches" the lamp arcstream and shuts it off if the lamp sputter blackens or suffers ion creep reducing its light output to uneconomic levels.
The two transistors hanging off pins 3 and 5 of the control chip are probably thermal feedback. They were mounted close to the bridge MOSFET's and under the same blob of thermally conductive putty.
This circuit had failed because the lower left hand MOSFET had shorted and the fuse links blew gently. There seems to be no other damage and I feel I can repair it if I can get a replacement MOSFET of the same type. Having it operating on the bench off the isolation transformer and truely grounding its live ground so that waveforms can be measured with the oscilloscope will reveal much more of just what this circuit does and how it does it.
Certainly, from a sheer complexity point of view, the low reliability Kev and others routinely observe is explained. The engineer's reliability equation counts a chip as a single component, despite however many millions of transistors and resistors are integrated inside it. All other discrete components are counted in the equation and the more there are, the less the reliability.
Critical Comments Please, I feel I'm the only one addressing electronic control gear here!
Andrew

P.S. Danny, Love the old B22d capped tubes, beautiful rare things! I've never seen them with the B22d-2/38x30 large collared caps.
Attachments
Tridonic_ Atco.jpg
Circuit of Tridonic-Arco HQI_TS 70W Electronic Control Gear.

User avatar
MetalHalideHater
Posts: 162
Joined: Sat Jul 02, 2011 6:31 pm
Contact:

Re: Control Gear for Osram Endura

Postby MetalHalideHater » Thu Jun 07, 2012 9:23 am

I sort of understand what's going on there. I'll have another look once my brain has fully comprehended the diagram.

User avatar
Kev
Posts: 1184
Joined: Wed Jan 05, 2011 10:32 pm
Favourite Manufacturer: Atlas and CourtneyPope
Area of interest: Discharge and Fluorescent
Location: Cornwall
Contact:

Re: Control Gear for Osram Endura

Postby Kev » Thu Jun 07, 2012 3:45 pm

I Dislike electronic control gear due to the reduced reliablilty of it. In commercial enviroments it is not uncommon to have to replace the ballast before the first lamp has failed.
This is pathetic IMO so i try to stay as much magnetic as i can. At least they are servicable.


Return to “Control Gear”

Who is online

Users browsing this forum: No registered users and 1 guest