I just installed a DH163 decoder in my Kato SD45 diesel and when I ran it on my DC layout the headlamp bulbs did not light. Did I burn the bulb out or will the bulb light when I convert to DCC? If I need to add a resistor, what size? I don’t want to burn any more bulbs out on the rest of my Kato diesels.
Out of the box, the lights will not light on DC. You have to program what function will be enabled when running under DC.
Ont he other hand - I think you got lucky because of this. I’m not certain, but I think the Kato locos use low-voltage bulbs, and if you ran this on DCC and turned on the headlight, it would have blown. And a lot of times when you blow up the bulb like that, it also damages the function output on the decoder.
If they are low voltage, you need to know what voltage and what their current draw is to calculate an appropriate resistor.
Even if it is a 12v bulb, a small value resistor is a good idea, to protect the decoder outputs from the high inrush current of a light bulb filament. And given that under DCC the light will be on at FULL power ALL the time, replacement with a resistor and low voltage bulb or LED isn’t a bad idea, too much heat can melt the plastic. Running on DC, the bulb probably wouldn’t be much above half brightnes most of the time and isn’t a problem, but with the constant voltage output of DCC, it can be.
–Randy