But would it do better enough to justify the extra cost?
Downlight transformer
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Anybody know what they do in cars for all the LED lights at the back? The BASmobile is too old and too non-premium for it to have any....
Possibly all the CANBUS malarkey. That and contributing to a gouging price for a part which has to be replaced in its entirety and not repaired or re-lamped.
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I suspect that, if mass produced, the cost difference would probably be pretty marginal. In any event, aptsys has pointed out some other potential reasons for not using the 'two component' solution.
Kind Regards, John
Almost certainly it drives the LED element(s) with pulsed DC that averages out at or below the rated continuous current for the element(s).
This makes the LED element(s) appear to be brighter thanb if they were drive with the rated continuous current for the element(s).
Take a CCTV or video of a car's LED lamps and you may find the light that appears steady to your eye is pulsing when viewed via the CCTV
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The rear light clusters have constant current boost regulators along with the microcontroller for interfacing with the MS CAN bus. The LEDs are a single series string of LEDs so that the LEDs are all matched (hence the boost regulator). No pulsing or anything like that.
I've often wondered, is there anything in the MoT regarding the number of LEDs that can fail before the light is no longer acceptable?
I presume the individual LEDs could be replaced (anything is possible) but I suppose a whole new light assembly is normally the only way to go.
I presume the individual LEDs could be replaced (anything is possible) but I suppose a whole new light assembly is normally the only way to go.
Maybe they have a tool to measure the brightness if suspect, I recall people failing when they used to black out the red perspex covers
They certainly measure the brightness of headlights and, I think also brake lights, but I don't know about others.
It's a sore point with me. My ancient car always used to have excellent headlights. However, a few years ago (when they still seemed excellent) it failed its MOT because they were 'no bright enough' and so they were replaced (and the MOT then passed). The problem is that, ever since that replacement, I haven't been able top see where I am going at night!
Kind Regards, John
That would be none, that would:
Although I don't know what voltage they are, to be in series with a 12V supply, as some cars have several 10's in each "brake light", "rear light", "turn indicator", and so on.
The last reminds me, on some cars that PCB will contain a sequencing function - some turn indicators don't just go wholly on-off-on-off etc. Whether as a society we really need that sort of thing is open to question, as is whether it should be allowed.
I replaced it because it was cracked, probably by a heavy-handed binman flinging the bin across the road. It contained about three replaceable bulbs, and an LED assembly (might have been the stoplamps)
So it was only the plastic cover which needed replacing, not the whole thing...
Looking at the CCTV of cars passing many head lamps and indicators are strobing ( pulsing ) as a result of the LEDs being pulsed and the camarea shutter not being synchronised. ( beat note )
Also the temporary traffic signal LED arrays are diveded into two half and pulsed alternatively. To the naked eye they appear as a round light, through CCTV they appear as two half moons flashing alternatively.
The destination boards on buses appear very strange trhough CCTV
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