heathyoung
04-06-2008, 09:22 AM
Just a quick warning to people running high wattage bulbs (eg 100/80's) with relays - don't be tempted to run both filaments at the same time!
The reason why is that the return wire between the two filaments cannot take the current of both at the same time, and becomes a fuse - so the lowbeam and highbeam filaments are now in series with each other to ground. Result - 6V across each filament which results in a combined output of about 200 lumens. :rant:
I have a bike light that runs a single 12V 20W MR16 downlight bulb that is brighter than this.
You have to turn the dash lights down as far as they go to see anything :(
I just drove to work at 4 AM on a pitch black country road with nothing but candles for headlights. Ugh. At least both the low and highbeams were on, so there was decent reflection on the catseyes + signs. Highbeam H1's still worked thankfully.
Just a gentle warning. I rewired mine when a relay died, thats what you get for being lazy. :nuts:
The reason why is that the return wire between the two filaments cannot take the current of both at the same time, and becomes a fuse - so the lowbeam and highbeam filaments are now in series with each other to ground. Result - 6V across each filament which results in a combined output of about 200 lumens. :rant:
I have a bike light that runs a single 12V 20W MR16 downlight bulb that is brighter than this.
You have to turn the dash lights down as far as they go to see anything :(
I just drove to work at 4 AM on a pitch black country road with nothing but candles for headlights. Ugh. At least both the low and highbeams were on, so there was decent reflection on the catseyes + signs. Highbeam H1's still worked thankfully.
Just a gentle warning. I rewired mine when a relay died, thats what you get for being lazy. :nuts: