Colin

If the led's worked in analoge mode ( without a chip), you'be be safe to asume that the PCB board that contains the led's has the proper resitors to bring the voltage down from the 12v track power to the ≠ 2-3 volts sustainable by most led's.

If one uses the slot.it chip in combination with the SP16 light kit (read the manual carefully for the different connection for SSD) you would also have your lights working while the car is stationary. You'll have the added capability to turn the lights on and off and have a very stable 5 volts to feed the lights.

with kind regards
Tamar

 

Hey Colin

Scaley works on 12v alternating, so my understanding is that you need a bridge rectifier to convert the power to full dc or just a diode (if you are willing to ditch half of the sine wave of power). I myself have used just a single diode on the headlights connected to the braids and I haven't had an issue. The lights look fine to me this way as well.

Heath

 

The most elegant solution is a bridge rectifier because that converts the entire sine wave of the AC into DC to drive the LEDs. In practice many people say a simple diode to allow half the Sine wave through to power the LED gives an insignificant reduction in brightness.

Wire each LED independently because pairing them up always results in one being brighter than the other.

If your LEDs are bare then you need a resistor (anything from 470 ohms to 560 ohms) anywhere in the circuit in series with the LED. If they are the prewired type then they already have a resistor usually for 12V.

Put a diode on the cathode side of the LED (you can share the diode with both LED circuits if you like).

The diode needs to be fast switching - I find the 1N4148 to be ideal and it's cheap. 99p on evilbay for 10 - or £1.40 for 50!!! (yeah I know).

Why the diode? Yes LEDs are diodes BUT they are not strong diodes and, although they are supposed to resist current going the wrong way through them, LEDs are weak in this respect and reverse voltage of 12V can kill them. A proper diode like the 1N4148 is strong and stops the reverse voltage getting to the LED.

 

And people like me, who don't know or care, just hook the lights up to the pickup leads and call it good.
Haven't lost an LED yet.

 

Hi
Yes,I'm with you on that one Greg,before I found this forum I did this with a Ford Focus rally car and a Maserati mc12 and they worked perfectly,mind that was with c7030 and that had twelve volts to the rails.

The voltage on the rails is not straight ac,if it was led's would not work as above.

 

I second Greg, I have a lot of cars with lights always on hooked up directly to the ac without any blown LEDs.

 

All of my cars with lights are run off ICP chips ....... so easy ...

 

Thanks for all the replies, I'm just doing some cars for a friend but don't have time to do ICP or for that matter mess about with extra parts, was hoping I could just add them at the front end of the chip. Not my cars so I think I will leave them off the motor rather than risk damaging someone else's cars.