Quick diode question

[BASS-TREBLE]

Bought some new halogen headlights to be used as a stacked streetfighter set up.
2 units, will use 1 for low and 1 for high.

I came up with this wiring so that I can run both low and high when switched to 'high' beam.

Want to use the relay to avoid frying stock switch/wires.

I have done electrical work but never actually used diodes apart from LEDs, I know how they work etc.

Need this diode to stop the low beam activating the relay.
What diode would I need for this application? Ratings etc? I suppose dick smith will have some.

Cheers.

[CookMySock]

1 amp, 200 PIV will be heaps.

DSE 1N4004 - 20c

EDIT: OOPS, I thought you were running a relay with it. You will need a 10A diode to do that. Not recommended - it will get hot. Use relay on the low beam, as well. Use the 1N4004 diode to turn the relay on.

edit again: You have to be careful doing things like this. If you stuff up, your lights go out. Um, bad.

Steve

[BASS-TREBLE]

edit again: You have to be careful doing things like this. If you stuff up, your lights go out. Um, bad.

Steve

Thats the main concern.

I can't work out any way to have both low and high lights on when using 'high' without a diode in there somwhere, damn it!

edit; unless I have the low hardwired on, I might just do that because I always have it switched on anyway.
No warrant issues with that is there?

[CookMySock]

WOF, dont think so. You will have to ask them that. Bear in mind you might overheat the lamp and the connector on the back of the bulb. Wiring lowbeam on permanently will work well.

Why do you want both filaments on? Do you have the power budget to run them both?

Steve

[BASS-TREBLE]

Reasons for both, they are single filament halogens. So having both on won't overheat lamps and give more light.

FZR stock has double headlights, so stock highbeam its running 2x60w = 120W, 2x these new holgens will be a total of 150w, stuff all more.

Ive decided to wire low beam just after the lights on/off switch and cut out low/high beam switch for it,
then run a relay for high beam lamp triggered by the normal high beam wire, if that makes sense

[Hinny]

Better off with double filament bulb in low beam unit IMO.
Get rid of the light spread in close so you don't have to look through it to see into the distance. It's like looking through a fog.
Why wouldn't just using two relays work?

[BASS-TREBLE]

I would prefer double filament but the halogens are just singles.

Trying to use components that I have lying around, which is only one relay, and = less wiring

[JMemonic]

Use the relay to cut the power to the high rather than supplying it, far easier and no diode needed

[CookMySock]

Get rid of the light spread in close so you don't have to look through it to see into the distance. It's like looking through a fog.

Yeah I agree. Running lowbeam constantly wont improve your night vision.

Why wouldn't just using two relays work?

It will. The most unreliable part of automotive wiring are the connectors, only surpassed by the bulbs themselves. It's unwise to triple the number of connectors on your lowbeam headlight. One day one of them will fail - often resulting in a bad fright.

Steve

[JMemonic]

The most unreliable part of automotive wiring are the connectors, only surpassed by the bulbs themselves. It's unwise to triple the number of connectors on your lowbeam headlight. One day one of them will fail - often resulting in a bad fright.

Steve

Even worse than the connectors is those vampire taps that you clip over the wire and pierce the insulation, solder and insulate joins where possible, if you cant then use automotive connectors that have a fully covering body even on earth wires then seal where you can.

[CookMySock]

Even worse than the connectors is those vampire taps that you clip over the wire and pierce the insulation, solder and insulate joins where possible, if you cant then use automotive connectors that have a fully covering body even on earth wires then seal where you can.

Agreed, but soldering isn't that great either. Soldered joints corrode and theres no stress-relief so they eventually snap. The only way to insulate them is to tape them up, and that just falls off unless it's self-amalgamating tape, and then that stuff is expensive, hard to find, and sensitive to oil.. ie, you can't win.

The best I have found is the correct size crimp terminal, and a heavy duty professional crimping tool (not a pressed steel repco one), followed by the yank test. Crimp it up and pull hard on it - if it comes apart, check your method and do it again.

Steve

[jonbuoy]

Twist the conductors together then solder then glue filled heatshrink over the top. Hard to get decent solder join on old corroded wiring though - plenty of flux and cleaning. If its soldered properly you won´t get a dry joint. EDIT - Just use a double pole relay as shown, this way should be fairly fail safe too, I added a diode to the relay for back EMF protection to stop your high low switch burning out after a couple of years.

[JMemonic]

Twist the conductors together then solder then glue filled heatshrink over the top. Hard to get decent solder join on old corroded wiring though - plenty of flux and cleaning. If its soldered properly you won´t get a dry joint. EDIT - Just use a double pole relay as shown, this way should be fairly fail safe too, I added a diode to the relay for back EMF protection to stop your high low switch burning out after a couple of years.

I thought the same on the circuit but given the original question how to leave the low beam on an switch the high in it was easier to just use one relay.

Also unfortunately DPDT automotive relays (thus sealed) don't seem to be that common, most DPDT relays are fine for decent AC current but not DC we are talking 120 watt bulbs at 12 - 13 volts so looking at 9.3 to 10 amps per bulb and if there is 2 potentially up to say 22 amps allowing for any connector resistance/voltage drop or low battery scenarios.

[jonbuoy]

I thought the same on the circuit but given the original question how to leave the low beam on an switch the high in it was easier to just use one relay.

Also unfortunately DPDT automotive relays (thus sealed) don't seem to be that common, most DPDT relays are fine for decent AC current but not DC we are talking 120 watt bulbs at 12 - 13 volts so looking at 9.3 to 10 amps per bulb and if there is 2 potentially up to say 22 amps allowing for any connector resistance/voltage drop or low battery scenarios.

RS have heaps of 12V DPDT relays that will do the job. Automotive ones aren´t that well sealed - tuck it somewhere dry ish - fresh water won´t do it too much harm. None of the normal switches on the handlebars are sealed either. Edit - a 12v 16A double pole normally open is all thats needed.

[CookMySock]

I actually wonder if its legal to have both full and dipped beams on simultaneously.

Stick with modern automotive electrical equipment - dont hack with backyard dick smith electronics fashion jewelry on your bike - not the dipped beam anyway - you need this to work.

Steve