Mick Forey Posted January 30, 2020 Report Share Posted January 30, 2020 Has anybody has any experience with these bulbs: http://www.norbsa02.freeuk.com/goffyWhyNotLEDs.htm? I bought a pair as they sounded just the thing to improve the lighting and reduce current from my dynamo from the TR3's tripod headlamps. The LEDs are in two banks, one on either side of the bulb. On dipped beam only one bank of LEDs lights up, on main beam both banks light up. I tested one bulb out on the bench to find this out. I fitted them and had some really strange results. On main beam they work brilliantly, lots of bright white light and the ammeter hardly moves. Just the job. However, on dipped beam the dipped beam elements are on all the time but the main beam LEDs also come on. I asked the supplier for help and he stated that sometimes the main beam warning light causes such problems. Therefore I removed the warning bulb holder from the back of the speedo. On repeating the test the dipped beam LEDs stay on all the time but now the main beam LEDs flick on and off randomly. Great for Christmas but not good for the road. I have done further testing by unplugging the main beam wires from the headlamp unit to the loom and measuring voltages etc. If the main beam wire is disconnected then dipped beam works fine. By applying the voltmeter to the main beam cable coming out of the headlamp unit, this turns the main beam LEDs on. Voltage starts at approx 6v and decays away to less than 1v. As the voltage deyas the main beam LEDs stay on for longer. Given the high resistance of a voltmeter, it clearly requires almost no current to turn the LEDs on, therefore they must be getting their power supply through the dipped beam cableand the electronic within the bulb are doing the rest. Bizarre. Any ideas or help gratefully received. Mick Quote Link to post Share on other sites
Waldi Posted January 30, 2020 Report Share Posted January 30, 2020 Hi Mick, Could it be a poor earth issue. Maybe try an additional earth from the bulb connector to a good earth point. Waldi Quote Link to post Share on other sites
RobH Posted January 30, 2020 Report Share Posted January 30, 2020 (edited) edited- Mick when you tested the bulb on the bench did you power only one line at once? e.g only the dip for dip beam and only main for the main beam? I think Graham is on the same track below - the light switch on a motorcycle may work differently. Further thought.- In the car the bulbs are connected together in parallel and there might be something about them that doesn't like that and interacts. If you disconnect one bulb, does the remaining one then work OK? Edited January 30, 2020 by RobH Quote Link to post Share on other sites
Grahamgl Posted January 30, 2020 Report Share Posted January 30, 2020 Would your problem be anything to do with the bulbs being advertised as motorcycle bulbs? Graham Quote Link to post Share on other sites
Nigel Triumph Posted January 30, 2020 Report Share Posted January 30, 2020 Don't know if it helps solve this particular puzzle... Like the sealed beam units and replacement headlight bulbs on our cars, classic motorcycle tungsten filament bulbs are supposed to have power to either main OR dip filament, not both together. Nigel Quote Link to post Share on other sites
Lebro Posted January 30, 2020 Report Share Posted January 30, 2020 (edited) 6 hours ago, Mick Forey said: Has anybody has any experience with these bulbs: http://www.norbsa02.freeuk.com/goffyWhyNotLEDs.htm? I bought a pair as they sounded just the thing to improve the lighting and reduce current from my dynamo from the TR3's tripod headlamps. The LEDs are in two banks, one on either side of the bulb. On dipped beam only one bank of LEDs lights up, on main beam both banks light up. I tested one bulb out on the bench to find this out. I fitted them and had some really strange results. On main beam they work brilliantly, lots of bright white light and the ammeter hardly moves. Just the job. However, on dipped beam the dipped beam elements are on all the time but the main beam LEDs also come on. I asked the supplier for help and he stated that sometimes the main beam warning light causes such problems. Therefore I removed the warning bulb holder from the back of the speedo. On repeating the test the dipped beam LEDs stay on all the time but now the main beam LEDs flick on and off randomly. Great for Christmas but not good for the road. I have done further testing by unplugging the main beam wires from the headlamp unit to the loom and measuring voltages etc. If the main beam wire is disconnected then dipped beam works fine. By applying the voltmeter to the main beam cable coming out of the headlamp unit, this turns the main beam LEDs on. Voltage starts at approx 6v and decays away to less than 1v. As the voltage deyas the main beam LEDs stay on for longer. Given the high resistance of a voltmeter, it clearly requires almost no current to turn the LEDs on, therefore they must be getting their power supply through the dipped beam cableand the electronic within the bulb are doing the rest. Bizarre. Any ideas or help gratefully received. Mick Hi Mick. From time to time I do some testing for one of the LED bulb suppliers (Classiccarleds) Last year I tested what was to be "the production version" of a bulb I had previously looked at, & after some modifications I was happy with. I was testing the BA15 version of your bulb. After testing the 2nd version I wrote this report: Hi Duncan. Have done a few tests on the BA15D bulb, & here are my comments: 1) Very similar in appearance to previous version, but different method of construction, same LED's, same brightness, same current draw I'm sure these will have the same beam pattern as before, but could not test (see notes 2 & 4) 2) The orientation of the base to the "top & bottom" of the bulb is 90° out, 3) Bench testing using a power supply showed that one terminal lit one side only, & the other terminal lit both sides This is correct, & is how the previous test bulbs left me. 4) Unfortunately when fitted to the Austin 12 (same one we used last time) The bulb did odd things, full beam worked OK but switching to dipped beam momentarily switched off one side, but it then came back on again. we thought this might be interaction with the other headlamp, which still had the normal bulb in, but when we removed that bulb the dipped condition resulted in one side being on, & the other side flashing rapidly on & off. we did not experience these problems with the previous test bulbs, so backward progress there. I think we were much nearer the desired result last time. Cheers Bob. So you are not alone, & I suggest you try to get your money back as there is clearly a design problem. The 1st version I tried did not have that problem, & although were no where near as good as the H4 types you can get, they were an improvement on the original filament bulbs. Bob. Edited January 30, 2020 by Lebro Quote Link to post Share on other sites
ctc77965o Posted January 31, 2020 Report Share Posted January 31, 2020 Hey Mick, I work in the LED industry & headlamps are an important business. Remember LEDs are naturally Diodes...sometimes designs rely on this 'one way' behaviour and if one individual chip is faulty (not a diode) then the whole circuit misbehaves. In your volt meter tests, I guess its a negative earth bulb and you were applying +12V to the low beam and measuring Volts between hibeam terminal and 0V? Is it a LCD or Needle type voltmeter? (big difference in impedance) When the main beam LEDs are on, can you look at them (maybe with sunglasses or welding goggles)? are all the chips the same brightness? is one dimmer or off? or got a dark spot? Another reason electronic circuits go wrong (an LED lamp is a compact electronic circuit) is damp ... if you put one of these lamps in a dry place (in a tupperware pot with dry rice, silica gel etc -or- a short bake in the oven at 80-100C) does it behave better? Dave Quote Link to post Share on other sites
Mick Forey Posted January 31, 2020 Author Report Share Posted January 31, 2020 Thanks for all the replies. I think Bob has hit the nail on the head, it is a design fault. I will try to get my money back. Dave, both bulbs behave in the same way. It was an LCD type voltmeter. All of the diodes are equally bright. The bulbs are sold as suitable for both negative and positive earth. My TR3 is negative earth (after I fried a friend's iPhone on the dash). I wonder if the circuit that detects polarity and switches the LEDs polarity is responsible for this behaviour. Many thanks, Mick Quote Link to post Share on other sites
TorontoTim Posted January 31, 2020 Report Share Posted January 31, 2020 On a slightly different tack, I bought some BPF spot/fog bulbs for my Lucas rally lamps. As the "usual" supplier, see Bob's post above, doesn't currently offer any of these pending a redesign, I bought from an ebay merchant. Error. These were, frankly, bollocks. No focus at all and just a general wash of (nice, white) light - not appropriate for the task at all. Halogens are back in. Bob - give us all a shout if you see any of these become available that are actually good!! Cheers, Tim Quote Link to post Share on other sites
Lebro Posted January 31, 2020 Report Share Posted January 31, 2020 Will do ! Quote Link to post Share on other sites
RogerH Posted January 31, 2020 Report Share Posted January 31, 2020 6 hours ago, Mick Forey said: Thanks for all the replies. I think Bob has hit the nail on the head, it is a design fault. I will try to get my money back. Dave, both bulbs behave in the same way. It was an LCD type voltmeter. All of the diodes are equally bright. The bulbs are sold as suitable for both negative and positive earth. My TR3 is negative earth (after I fried a friend's iPhone on the dash). I wonder if the circuit that detects polarity and switches the LEDs polarity is responsible for this behaviour. Many thanks, Mick Hi Mick, the polarity switching circuit will be a simply bridge rectifier or similar. No switching as such. Roger Quote Link to post Share on other sites
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