LED lightbulb replacement?

AIUI no regulation has so far been retrospective, but the C&U regulations in force at the time of manufacture has to be complied with OR if any modifications are done they MUST comply with current regulations.

In sort, leave the car as designed and or built and you'll have little problems, start changing things covered by C&U or EU regulations and you just might if you don't comply with current thinking IYSWIM.

Then I'd say you'd used the wrong alternator. I had one on a P6 which was near useless - and it wasn't the earliest one which had a separate regulator which was fine. But most modern ones are very good indeed.

So saying, most alternators are set to not *fully* charge a battery to allow low maintence types. This shouldn't be a problem in practice, though.

I'm not quite sure what you mean. Most alternators are still stand alone units. However, if it has an output of some 100 amps plus, as many do, you'll need a rather more sophisticated regulator than smaller ones - but then this would apply equally to a dynamo.

There really is little difference between them at normal engine speeds if they have the same output - a dynamo can benefit from electronic control as much as an alternator. But an alternator, through not having a commutator, can be run at a much higher speed which gives a better low engine speed charge.

Things like heated rear windows and all the rest of the electrical bits and pieces we now take for granted weren't common then, so a 30 amp dynamo

- or less - could cope. Even small cars have ones with 3 times that output now - or even more.

As would HID headlamps.

I think you would have if you did a typical London commute with headlights on for long periods in traffic jams. When dynamos were the norm, people didn't use headlights much in town.

You could make up your own 'bulb' using several LEDs pointing in different directions - it's easy to get nine standard 5mm LEDs and dropper resistor in the space occupied by a normal 21 watt bulb. This is what I've done on the SD1. Messes up the bulb failure unit, though.

In article , Dave Plowman writes

Don't you believe it! I work on vehicle electronic systems (particularly engine management computers, but not exclusively), and things like smart alternators and computer mapped charging have been on cars as humble as the Ford Focus for a while now. Yes, a lot of that is to do with the higher output alternator, but not because they're any harder to control. The main point is that an alternator is a voltage regulated device. If you have a crude regulator it will attempt to charge a flat battery at maximum current. Car batteries really don't like being charged at 30 amps or more, especially on a cold morning.

Granted the difference is not related to the dynamo being a DC generator. It is to do with the control box. It happens that the old electromechanical control boxes were kinder to the battery than old style alternator electronic regulators.

Very true - the key factors are the use headlights and heated rear windows, as most classics don't get used durring long winter nights a dynamo is fine, reliable and easy to fix. On the otherhand if you have a car loaded with electrics and an undersized battery such as many british specialist sports cars of of the 60s/70s don't expect to use it through the winter without fitting a decent alternator and a have duty battery.

snip

Slightly off topic but for "home built vehicle" SVA testing the examiniers have now been given a degree of discretion with regard to rear lights -- the idea being that they no longer have to demand "e" marking but if the recognise a lamp as a type meeting C & U requirements they can pass it.

Well, given just how cheap electronics are in mass production, it makes sense to tailor the charge to the best possible match to a battery. And if for some reason dynamos were still in use, it would have been applied to them too. But I still reckon it's more to do with reducing battery maintenance than any other reason.

Most dynamos had an output of under 30 amps, so it's not like for like. And in the days of dynamos, you were constantly topping up batteries. I don't think a low maintenance type would last very long if it wasn't regularly topped up.

I'm glad alternators were 'invented'. Just about every car I had with a dynamo gave trouble, and they were more expensive to fix than the average alternator fault.

In article , Dave Plowman writes

Well, as I said earlier in the thread, my old 1968 Vitesse with dynamo and electromechanical control box never gave me any trouble. The battery was a low maintenance type (though decidedly old by the time I got the car) and never had to be "topped up" in the time I owned it.

Just do a search on the web. That price is way OTT by the way, £18 a pair is nearer the mark.

Sadly they're not E-marked and therefore illegal on UK roads. Which is a shame as I was hoping to replace the brake lights on my wife's Previa which seems to blow normal bulbs about once a month (LEDs of course are longer-lasting).

Looking at the couple of bulbs - not headlight ones - I've got to hand, they're not E-marked either. Sure it applies to bulbs and not just the fittings?

I think you will find they are grey imports from the former Soviet block and some parts of the far east that aren't e marked as automotive bulbs. Puka automotive bulbs (even side lamp bulbs) are E marked either stamped on the ferrule or etched on the glass, it should also state it on the packaging.

Surely you're more likely to get stopped by the fuzz for lights that don't work than for having lights that do? Unless the aforesaid gentleman in blue was another Previa owner of course;-)

Ron Robinson

I went into the local Autotits today and asked about them - No sign of any marks or anything, nothing on the packet, and 13 quid a pop... The chap there had a look and said "They'd say if they weren't for road use on the packet, wouldn't they?". So there you go, buy them from him, and use that as a defence in court if stopped...

I do wish that people that sell these things had a clue about the legalities. I'm still not sure one way or the other on LED lights, but I'd expect someone who sells them to put my mind at ease one way or the other! when I bought an exhaust once, the person in the shop said "Is it for road use, as you know you can't use that particualr one other than off road/ on the track?". I lied through my teeth, and said it wouldn't be used on road, but at least the seller had enough of a clue to tell me the legal side of things, with the chance of losing a sale...

Well I'm not really sure about this. But I did not that a number of the websites selling these did actually state "May not be legal on UK roads" or "Off road use only".

Well yes, that would be my way of thinking. It just seems crazy that with BMW for one fitting them as standard, also on buses, and I noticed yesterday, traffic lights, they are obviously up to the job, so why hasn't anyone got round to declaring them legal in general terms?

The process of type-approval is not exactly cheap; if you are an OEM parts manufacturer like, say, Hella or Bosch who's going to be selling considerable numbers lights/bulbs as complete units to mainstream manufacturers then you can spread the approvals-cost over the entire production-run.

If you're a backstreet Taiwanese manufacturer intent on scoring a quick buck and plan on using the cheapest possible bits-and-pieces you can get your hands on, then you don't bother with the approval process.

Or alternatively you forge the approvals-certs and sell your product in "lookalike" packaging - which seemed to be the case for a local parts-supplier who recently tried to sell me a spurious fuel-filter which was in a carbon- copy of a Bosch box, except it said "BOSGH" not "BOSCH" on it....!

I think you'll find that traffic lights are fibre optic rather than LED (like the new banner repeaters on the railway) but I could be wrong. Flashing led lamps on bicycles aren't legal but they're a good idea and are widely used. I don't think you'll get stopped for having led lights as long as they're bright enough, the right colour and in a sensible position. If they're behind a normal lens you won't be able to tell if they're E-marked or not.