Lumenition Optronic info needed! - UK Vintage Radio Repair and Restoration Discussion Forum

mole42uk · 21st Jul 2016, 3:18 pm

Hi,

I am trying to interface the optical pickup from a Lumenition Optronic system to another ignition module. The pickup uses a 3-wire interface, +ve, GND and signal. The only data I can find about the pickup is that the positive voltage is approximately 7.2 and the switching transistor is stated to switch between 1.0 and 2.7v

I think I should be able to make a simple resistor divider to obtain 7.2v from the nominal 13.8 vehicle supply and apply the output to the input of the ignition module.

Does anyone have any experience of the Optronic module or even have some more data?

Ta,

21st Jul 2016, 4:13 pm

I am guessing this is a combustion engine ignition system, they are quite robust both in supply voltage and trigger voltage required. My other guess is that the pickup is an LED/phototransistor combination, feed the LED with 10mA or so and just connect the transistor to the other modules input. It's all guesses based on what was done in the past.

mole42uk · 21st Jul 2016, 4:27 pm

Apologies, I did write a piece about the technology but must have edited it out!!

It is indeed an ignition system for petrol engines, using an IR LED, a phototransistor and a slotted chopper disk to provide timed pulses between about 60Hz and 800Hz.

VT FUSE · 21st Jul 2016, 4:42 pm

Fitted one of these to a BDA engine in a Westfield Hill climb car that I built between 1987 and 1990.

Only the scantest tech documentation was supplied,so much so that I burned the potted finned control module out by having ignition in "on" position while messing with fuel pump but engine stopped for just 10 mins.

Had to buy a new system as was deemed to be my fault-still have the scar from touching the blistering hot casing.

The trigger was a IR photo diode combo with an interposed 4 segment plastic optical chopper device that pushed over the distributor cam lobes for keying location.

After this experience,I always remembered to disconnect the 3 way MOLEX connector when doing similar work. A very expensive lesson at the time and gave me a long lasting distrust in brand.
A friend showed me one fitted to the engine of the pump on a fire engine later,I was quite concerned by this.

Good luck

Malcolm G6ANZ · 21st Jul 2016, 5:33 pm

Hi Richard, try here
http://www.holden.co.uk/displayprodu...50#prettyPhoto
or here
http://limpexautosport.nl/wp-content..._Bulletins.pdf
Malcolm

ms660 · 21st Jul 2016, 7:26 pm

Quote:

Originally Posted by mole42uk

Does anyone have any experience of the Optronic module or even have some more data?

No data, but I have had some experience with a Lumenition system, that experience was top notch, I fitted one to my old Air Portable S111 Landrover, it worked faultless for the twenty years I had the vehicle, the engine never missed a beat or backfired due to ignition problems and I drove that old Landrover through some tough times/terrain, I know the bloke I sold the vehicle to and the Lumenition is still spot on, well worth the money.

If installing the opto coupler then make sure the three wires have enough play in them to account for any vacuum advance movement etc.

Good luck with it.

Lawrence.

mole42uk · 21st Jul 2016, 7:47 pm

Thanks Malcolm et al. I have a good experience with the Optronic system in my car and have no reason to suspect it of unreliability or failure. We used to use Lumenition back in the early 70s in the Mini rally cars and they were always bullet proof.

In this case I have a programmable ignition system from Australia that I want to try out. It replaces the Lumenition module with a similar one but the design has options for points, reluctor sensing or Hall effect, not optical. Designing the interface to the Optronic sensor should be trivial but I would like to make sure that I have a design that a) doesn't damage the existing hardware and b) works in the middle of the safe area for reliability.

It seems that I will have to get the meter out and take some measurements, both static and dynamic to see whether they have incorporated any cleverness in the optical module, or whether it is, in fact, simply an IR LED and a phototransistor..

KeithsTV · 21st Jul 2016, 9:56 pm

Back in the early 80s I designed an electronic ignition system using a Hall effect sensor with an open collector output. I'd suspect output from the optical sensor would be similar so you'd probably be able to use the Hall effect sensor option. Testing should be fairly easy, with power applied to the LED and a pull up resistor on the output pin, the output should change when something opaque is inserted in the slot.

Keith

julie_m · 22nd Jul 2016, 8:17 am

An optical sensor most probably is a simple NPN phototransistor, and Hall effect sensors are also usually open collector outputs. So you should be able to connect straight to that; or maybe the "points" input, if the Hall effect input is in the wrong sense.

KeithsTV · 22nd Jul 2016, 12:55 pm

The points input may be connected to the 12V supply via a lowish value resistor to pass a 100mA or so through the points to try to keep them clean. The optical sensor would probably object to passing this amount of current.

If the sensor is the wrong sense it shouldn't be too difficult to add a simple inverter between the sensor output and the ignition unit input.

Keith

21st Jul 2016, 3:18 pm	#1
mole42uk Nonode Join Date: Aug 2010 Location: Resolven, Wales; and Bristol, England Posts: 2,614	Lumenition Optronic info needed! Hi, I am trying to interface the optical pickup from a Lumenition Optronic system to another ignition module. The pickup uses a 3-wire interface, +ve, GND and signal. The only data I can find about the pickup is that the positive voltage is approximately 7.2 and the switching transistor is stated to switch between 1.0 and 2.7v I think I should be able to make a simple resistor divider to obtain 7.2v from the nominal 13.8 vehicle supply and apply the output to the input of the ignition module. Does anyone have any experience of the Optronic module or even have some more data? Ta, __________________ Richard Index: recursive loop: see recursive loop

21st Jul 2016, 4:13 pm	#2
Guest Guest Posts: n/a	Re: Lumenition Optronic info needed! I am guessing this is a combustion engine ignition system, they are quite robust both in supply voltage and trigger voltage required. My other guess is that the pickup is an LED/phototransistor combination, feed the LED with 10mA or so and just connect the transistor to the other modules input. It's all guesses based on what was done in the past.

21st Jul 2016, 4:27 pm	#3
mole42uk Nonode Join Date: Aug 2010 Location: Resolven, Wales; and Bristol, England Posts: 2,614	Re: Lumenition Optronic info needed! Apologies, I did write a piece about the technology but must have edited it out!! It is indeed an ignition system for petrol engines, using an IR LED, a phototransistor and a slotted chopper disk to provide timed pulses between about 60Hz and 800Hz. __________________ Richard Index: recursive loop: see recursive loop

21st Jul 2016, 4:42 pm	#4
VT FUSE Hexode Join Date: Aug 2010 Location: Malvern, Worcestershire, UK. Posts: 347	Re: Lumenition Optronic info needed! Fitted one of these to a BDA engine in a Westfield Hill climb car that I built between 1987 and 1990. Only the scantest tech documentation was supplied,so much so that I burned the potted finned control module out by having ignition in "on" position while messing with fuel pump but engine stopped for just 10 mins. Had to buy a new system as was deemed to be my fault-still have the scar from touching the blistering hot casing. The trigger was a IR photo diode combo with an interposed 4 segment plastic optical chopper device that pushed over the distributor cam lobes for keying location. After this experience,I always remembered to disconnect the 3 way MOLEX connector when doing similar work. A very expensive lesson at the time and gave me a long lasting distrust in brand. A friend showed me one fitted to the engine of the pump on a fire engine later,I was quite concerned by this. Good luck

21st Jul 2016, 5:33 pm	#5
Malcolm G6ANZ Octode Join Date: Feb 2006 Location: Bristol, UK. Posts: 1,042	Re: Lumenition Optronic info needed! Hi Richard, try here http://www.holden.co.uk/displayprodu...50#prettyPhoto or here http://limpexautosport.nl/wp-content..._Bulletins.pdf Malcolm

21st Jul 2016, 7:47 pm	#7
mole42uk Nonode Join Date: Aug 2010 Location: Resolven, Wales; and Bristol, England Posts: 2,614	Re: Lumenition Optronic info needed! Thanks Malcolm et al. I have a good experience with the Optronic system in my car and have no reason to suspect it of unreliability or failure. We used to use Lumenition back in the early 70s in the Mini rally cars and they were always bullet proof. In this case I have a programmable ignition system from Australia that I want to try out. It replaces the Lumenition module with a similar one but the design has options for points, reluctor sensing or Hall effect, not optical. Designing the interface to the Optronic sensor should be trivial but I would like to make sure that I have a design that a) doesn't damage the existing hardware and b) works in the middle of the safe area for reliability. It seems that I will have to get the meter out and take some measurements, both static and dynamic to see whether they have incorporated any cleverness in the optical module, or whether it is, in fact, simply an IR LED and a phototransistor.. __________________ Richard Index: recursive loop: see recursive loop

21st Jul 2016, 9:56 pm	#8
KeithsTV Nonode Join Date: Aug 2007 Location: South Bradford, West Yorkshire, UK. Posts: 2,573	Re: Lumenition Optronic info needed! Back in the early 80s I designed an electronic ignition system using a Hall effect sensor with an open collector output. I'd suspect output from the optical sensor would be similar so you'd probably be able to use the Hall effect sensor option. Testing should be fairly easy, with power applied to the LED and a pull up resistor on the output pin, the output should change when something opaque is inserted in the slot. Keith

22nd Jul 2016, 8:17 am	#9
julie_m Dekatron Join Date: May 2008 Location: Derby, UK. Posts: 7,735	Re: Lumenition Optronic info needed! An optical sensor most probably is a simple NPN phototransistor, and Hall effect sensors are also usually open collector outputs. So you should be able to connect straight to that; or maybe the "points" input, if the Hall effect input is in the wrong sense. __________________ If I have seen further than others, it is because I was standing on a pile of failed experiments.

22nd Jul 2016, 12:55 pm	#10
KeithsTV Nonode Join Date: Aug 2007 Location: South Bradford, West Yorkshire, UK. Posts: 2,573	Re: Lumenition Optronic info needed! The points input may be connected to the 12V supply via a lowish value resistor to pass a 100mA or so through the points to try to keep them clean. The optical sensor would probably object to passing this amount of current. If the sensor is the wrong sense it shouldn't be too difficult to add a simple inverter between the sensor output and the ignition unit input. Keith