Headlamp relays

[andyf]

I know this has been discussed many times but my searching is not throwing up enough information and I cannot log onto the old site, I know Beans, Cobber and possibly Mildred have done write ups in the past but they seem to have disappeared (I can`t find them anyway).

I have decided to add relays to the headlights and would like to know how you have all done it. Where did you position the relays, do you use one per side per beam (4 relays) or just 2. If just 2, is it OK to use a 4 pin relay and take two wires off of the 87 terminal or a 5 pin with two 87 terminals?

Where did you break into the wires?

Any help appreciated.

Many thanks folks.

[Cobber]

Now it was a long time ago, so my memories are a bit vague, but I mounted the relays on the engine side of the radiator support panel, I probably intercepted the wiring in the vicinity.
You only need one relay per pair of lights ....so one relay for high beam and one for low beam. the trick is to use relays with a high enough amperage rating for the wattage of the bulbs used.
How ever I used 4 individually fused relays , the reason is if I was to blow a fuse at speed I wouldn't loose all lighting.
If you are only going to use 2 relays the it would be best to go for the 5 pin.

[andyf]

Thank you Cobber, your thinking was similar to mine, lose a fuse and you would only lose one light, so I will probably go with 4 relays. I thought of siting them either side of the radiator and tap into the wires by the headlamp plugs for easier wiring. Do you suggest taking the live directly from the battery?

[sonscar]

I bought connectors to match the existing wiring so as to keep it easy and simple and also used four fused relays.The power for these comes directly from the battery.My blog has some photos of my lamentable wiring skills.Steve.

[DutchTriumph]

How ever I used 4 individually fused relays , the reason is if I was to blow a fuse at speed I wouldn't loose all lighting.

You can use 2 relays and 4 fuses. Just put the fuses before each light.

[darrellw]

Odd Hedberg has a really nice write up, including part numbers to make a system that plugs into the harness. It mounts on the opposite side where the A/C relays would be if you have A/C. I plan to make that up some day.

The latest TWOA bulletin (38) has a article using some of the off-the-shelf relay kits (which really don't work well for a Wedge). That one connects under the "speaker" cover. It will take the load off of your light switch, but would still be using the original wiring path from the dash to the lights, so may not be as beneficial as a relay closed to the lights.

[andyf]

How ever I used 4 individually fused relays , the reason is if I was to blow a fuse at speed I wouldn't loose all lighting.

You can use 2 relays and 4 fuses. Just put the fuses before each light.

Oh good heavens of course you can, Why didn`t I think of that.
Thanks Peter.

[andyf]

I bought connectors to match the existing wiring so as to keep it easy and simple and also used four fused relays.The power for these comes directly from the battery.My blog has some photos of my lamentable wiring skills.Steve.

Thanks Steve I will have a look.

[andyf]

Odd Hedberg has a really nice write up, including part numbers to make a system that plugs into the harness. It mounts on the opposite side where the A/C relays would be if you have A/C. I plan to make that up some day.

The latest TWOA bulletin (38) has a article using some of the off-the-shelf relay kits (which really don't work well for a Wedge). That one connects under the "speaker" cover. It will take the load off of your light switch, but would still be using the original wiring path from the dash to the lights, so may not be as beneficial as a relay closed to the lights.

Where could I get a copy of the bulletin Darrell?

[Cobber]

The other advantages of using 4 relays is less load per relay, which of course will make them last longer and if you do lose a relay you still have light

[darrellw]

Where could I get a copy of the bulletin Darrell?

Hi Andy,

You will need to join the TWOA:

http://www.triumphwedgeowners.org/aboutjoin.html

-Darrell

[DutchTriumph]

Oh good heavens of course you can, Why didn`t I think of that.
Thanks Peter.

That's why we're here, helping each other.

[Stag76]

I'm wiring mine using one SPST light power relay per side feeding the pin on the light that is normally used for the ground,
and a hi/lo beam SPDT Switching Relay. The power and switch for the light power relays and the switch for the Hi/Lo beam switching
relay are supplied via a fusible link. A separate relay will supply the headlight flasher, grounded by the hi/lo beam switch flash position.
The light switch grounds the light power relays to energize them and supply the lights via fuses.
The SPDT hi/lo beam switching relay then grounds either the High or Low beams via pins 87(high) and 87a(Low) with pin 30 grounded.
On low beam, the switching relay is open, and NC pin 87a is grounded The hi/lo beam switch (hi-beam position) grounds this relay to energize it, and switches NC pin 87a off and NO pin 87 live. This pin will also ground the switching circuit of the Spot light relay, via a dash switch.

This means that only 150ma (1.8 watt) signals are being conducted by the headlight switch, hi/lo beam switch and spot light switch.
This cuts down on the wiring in the cabin to 4 signal wires and a hi-beam light wire, and reduces the current carried by the switches.

The headlight lift motors are also controlled by SPDT Relays switched by the light power relays ie. light power on = lights raised,
light power off = lights lowered.

This method won't work if you are using polarity sensitive LED lights.