Warning gents,If you have a MAN or late Merc tractor unit watch you dont get a PG9 for flashing tail lights on your trailer.If the trailer has LED lights they flash about 5 times a second(unless they are ballasted) due to the trucks electrical system sending a test signal down the line to check that you dont have a trailer lamp out.Ive heard of a couple of blokes getting suspended prohibitions from your friendly neighbourhood VOSA gruppenfuhrer so watch for it.
So what happens if you have a ‘third brake light’, like on some trailers I’ve seen, and you have one of these fitted…
ebay.co.uk/itm/Brake-Light-F … 33686ad23b
Will you get a tug?
Hmmm, interesting. I drive an MAN and whilst (obviously) I’ve not seen mine do that, I have seen others do it. Thought it was my eyes TBH as every time I glance away from LED taillights they seem to flash.
If I get pulled I’ll just tell them I was practising cadence braking, but very quickly! 
the maoster:
Thought it was my eyes TBH as every time I glance away from LED taillights they seem to flash.
so its not just me then
Bking:
Ive heard
Doesn’t mean that it is true.
I’ve heard that Vosa fine you £10 for every turn of the landing leg handle 
Have you seen it in writing 
LED’s flicker at 60 htz anyway, so ALL LED lights flicker (to see this, any of you with front facing cameras rewind and watch the screen when you pull up at LED traffic lights) are VOSA going to PG9 everything on the back of this?
Derf:
LED’s flicker at 60 htz anyway, so ALL LED lights flicker (to see this, any of you with front facing cameras rewind and watch the screen when you pull up at LED traffic lights) are VOSA going to PG9 everything on the back of this?
Doh! Never seen a truck with a 60 hz AC supply usually most use DC like, ya know batteries!!!
The long plug lead tends to get in the way a bit. Jesus!
redboxer850:
Bking:
Ive heardDoesn’t mean that it is true.
I’ve heard that Vosa fine you £10 for every turn of the landing leg handle
Have you seen it in writing
No but I seen plenty of monkeys drivin trucks that believe this sort of (zb)!!!
Derf:
LED’s flicker at 60 htz anyway, so ALL LED lights flicker (to see this, any of you with front facing cameras rewind and watch the screen when you pull up at LED traffic lights) are VOSA going to PG9 everything on the back of this?
The camera flicker is a function of the lens, not the lights. LEDs do flicker a bit, even under DC power but they go on and off so fast the human eye can’t register, unless there is an electrical feed reason. The camera flicker is due to the frame rate of the camera. TV tends to work off either 44 or 48 frames per second, i cant remember which.
If you watch the 24 Heures du Mans for example, the LED tail lights on most of the cars appear to flicker because there will be times in both the lights flicker and the frame rate of the camera, when the lens will shoot at a time the lights are not actually lit.The lamps are not faulty, its just the way they work. Programmes like TopGear and Fifth Gear have to work very hard with the frame rate at which they shoot to be sure that the LED running lamps work right.
It is next to impossible with two cars, and when you have 56 cars, all at different points on the track, all with different lighting systems, it is a mission in futility to try and get it working right.
As for the test signal thing, it doesn’t happen to our DonBur Deckers, which all run LED lights on all four sides. That is mated to Renault Premium, DAF XF and MAN TGX units. I assume, given the fact that the MAN is accused by the OP and the Renault definatly tests the bulbs on a regular basis, then ■■■■■ you off with a stupid bright white warning lamp in the middle of the dashboard, (bloody stupid frenchists) that our deckers have some form of capacitor or something which regulates the flow of the electricity to avoid flashing lights.
It could be this function which isn’t working in the case of people who have been issued prohibitions for thinking they are DJ Fresh on the M5.
Ours did this, we just put resistors in the lamps on the trailer, between the break line and earth I think? But it sorted the flickering out. The problem now is the light test button does not work, regardless if its attached to a trailer, just aborts!
Apparently… we’ll so MAN told me, if you tell them it will be pulling trailers with led lights they can turn it off if you spec it from new. But you do lose the light test function.
nsmith1180:
Derf:
LED’s flicker at 60 htz anyway, so ALL LED lights flicker (to see this, any of you with front facing cameras rewind and watch the screen when you pull up at LED traffic lights) are VOSA going to PG9 everything on the back of this?The camera flicker is a function of the lens, not the lights. LEDs do flicker a bit, even under DC power but they go on and off so fast the human eye can’t register, unless there is an electrical feed reason. The camera flicker is due to the frame rate of the camera. TV tends to work off either 44 or 48 frames per second, i cant remember which.
If you watch the 24 Heures du Mans for example, the LED tail lights on most of the cars appear to flicker because there will be times in both the lights flicker and the frame rate of the camera, when the lens will shoot at a time the lights are not actually lit.The lamps are not faulty, its just the way they work. Programmes like TopGear and Fifth Gear have to work very hard with the frame rate at which they shoot to be sure that the LED running lamps work right.
It is next to impossible with two cars, and when you have 56 cars, all at different points on the track, all with different lighting systems, it is a mission in futility to try and get it working right.
As for the test signal thing, it doesn’t happen to our DonBur Deckers, which all run LED lights on all four sides. That is mated to Renault Premium, DAF XF and MAN TGX units. I assume, given the fact that the MAN is accused by the OP and the Renault definatly tests the bulbs on a regular basis, then [zb] you off with a stupid bright white warning lamp in the middle of the dashboard, (bloody stupid frenchists) that our deckers have some form of capacitor or something which regulates the flow of the electricity to avoid flashing lights.
It could be this function which isn’t working in the case of people who have been issued prohibitions for thinking they are DJ Fresh on the M5.
The camera flicker is called a primary harmonic,LEDs do not flicker on pure DC,and the reason for the test pulse is that new MANs and Mercs have now got full can bus link with trailer lighting via EBS lead and trailer lighting module on new trailers instead of only measuring resistance values via the N susie which puts the warning light up as bulb filament boil off varies the circuit resistance.A shunt resistor should be put in parallel with the LED to “damp” the test pulse.
Bking:
Derf:
LED’s flicker at 60 htz anyway, so ALL LED lights flicker (to see this, any of you with front facing cameras rewind and watch the screen when you pull up at LED traffic lights) are VOSA going to PG9 everything on the back of this?Doh! Never seen a truck with a 60 hz AC supply usually most use DC like, ya know batteries!!!
The long plug lead tends to get in the way a bit. Jesus!
I was under the impression that the mains supply, as implied by the reference to a plug lead, was 50 htz. Hardly helpful to make a criticism on a technical point without the expertise to back it up. At this frequency very few people will see the flicker as the eye and brain conspire to smooth out the differences. By way of supporting evidence can you see a halogen light bulb on AC mains supply flicker? See also the effect of a still photo when a cathode ray TV screen is on (you’ll see lines across the screen).
There was a thread some while ago about this and IIRC the solution was to put a, normal, slave bulb in the circuit somewhere. It was something to do with the bulb test circuit I think.
Wiretwister:
Bking:
Derf:
LED’s flicker at 60 htz anyway, so ALL LED lights flicker (to see this, any of you with front facing cameras rewind and watch the screen when you pull up at LED traffic lights) are VOSA going to PG9 everything on the back of this?Doh! Never seen a truck with a 60 hz AC supply usually most use DC like, ya know batteries!!!
The long plug lead tends to get in the way a bit. Jesus!I was under the impression that the mains supply, as implied by the reference to a plug lead, was 50 htz. Hardly helpful to make a criticism on a technical point without the expertise to back it up. At this frequency very few people will see the flicker as the eye and brain conspire to smooth out the differences. By way of supporting evidence can you see a halogen light bulb on AC mains supply flicker? See also the effect of a still photo when a cathode ray TV screen is on (you’ll see lines across the screen).
There was a thread some while ago about this and IIRC the solution was to put a, normal, slave bulb in the circuit somewhere. It was something to do with the bulb test circuit I think.
Halogen bulb will not flicker on AC as it uses an incadecent filament which allows current to flow in both directions but as an LED is a diode it only allows the positive part of the wave to excite the electrons while the negative phase will be blocked, in effect the LED is acting as a rectifier to convert AC to DC.Very little heat is produced by LED systems whereas incandescent bulbs turn up to 80% of the energy consumed into infra red wavelengths.Also an incandescent element cannot cool down instantaneously but an LED can instantly stop pushing electrons into higher orbits so they cannot fall back into lower orbit by realeasing a photon of fixed wavelength as soon as the AC signal drops below 5 volts positive.LEDs use quantum shell excitation to produce single wavelength light not resistance heating which produces all of the visible spectrum.If you put a “slave” bulb in the circuit when the slave blows you are back to flickering lights better to put a shunt resistor of 15 ohms which will “lock” current flow to 2 amps and “drown” the test pulse to stop flicker.Mains voltage frequency varies between 58 and 62 hz.
And probably a lot of you are going WTF is this tow rag on about.But tell you boys some dumb buggers out there running banks but some bright mothers out there driving and repairing trucks.Bet old Einstien would have loved to be a road boy.
nsmith1180:
TV tends to work off either 44 or 48 frames per second, i cant remember which.
24
Derf:
LED’s flicker at 60 htz anyway,
No they don’t. A LED on a DC power supply is a constant illumination. No flickering.
Bking:
better to put a shunt resistor of 15 ohms which will “lock” current flow to 2 amps and “drown” the test pulse to stop flicker.
I was starting to suspect you had half a clue until you posted that complete load of utter ■■■■■■■■.
Yours sincerely, a real electronics engineer and not someone who has managed to copy something from Wikipedia.
The problem with putting load resistors in LED light installations is you end up partly defeating some of the object. Yes you won’t need to change the bulbs any more but you’ll lose the energy saving benefit of the LEDs.
LEDs are making it a safer bet to leave your sidelights on overnight in case there’s some ■■■■■■■■ traffic copper with time on his hands but if you have waste energy on load resistors it isn’t any safer bet really.
Conor:
Derf:
LED’s flicker at 60 htz anyway,No they don’t. A LED on a DC power supply is a constant illumination. No flickering.
So why if you roll your eyes behind a vehicle with LED’s do you see a flicker patten and you see a constant patten with normal bulbs?
muckles:
Conor:
Derf:
LED’s flicker at 60 htz anyway,No they don’t. A LED on a DC power supply is a constant illumination. No flickering.
So why if you roll your eyes behind a vehicle with LED’s do you see a flicker patten and you see a constant patten with normal bulbs?
Might have something to do with voltage regulation, I have CREE SMD ( Very bright LED) sidelights/DRLs on the car and they flicker almost imperceptibly when the engine is on (you have to roll your eyes quickly to see it) but when the engine is switched off and they’re running off battery only there is no flicker. My CREE headtorch, LED bikelights etc that run off batteries (pure DC) don’t flicker.
will read this lot again after Ive been out new years eve might make sensse then he he happy new year all