[TR] TR3A Fog/Spot Light Relay(s)

Randall TR3driver at ca.rr.com
Tue Jan 23 00:13:58 MST 2018

There is some (small) advantage in minimizing the overall length of the
wire, but otherwise no advantage to placing the relay near the powered
device.  In other words, having 4 feet of wire supplying power to the relay
contacts, and 1 foot from relay to load; is _exactly_ the same as having 1
foot supplying power to contacts, and 4 feet to the load.  Either way, the
current flows through 4 feet of wire.

And if you do need to use a longer run of wire, just go up a size or two.  8
feet of 10 AWG is about the same resistance as 5 feet of 12 AWG.

I used to run 90/120 watt halogen headlights, with the relay mounted by the
control box, and that worked out fine.

That said, this time around I wanted a slightly stealthier installation (and
used 4 relays instead of just 1), so I mounted them on the back of the
headlight buckets.
Totally invisible when assembled, but access is just removing the 3 screws
that hold the bucket into the front apron.

I don't have a photo to share; but the relays that implement my
tail/stop/turn lights are mounted to a bracket fastened to the panel behind
the brake and clutch master cylinders.  And the relay for the electric fan
is mounted to the inner wing above the driver's left knee.

Yet another hidden spot is on the passenger side, between the glove
compartment and the firewall. (That's where I put the circuit breakers for
the headlights.)

-- Randall 
56 TR3 TS13571L once and future daily driver
71 Stag LE1473 - awaiting engine rebuild
71-2-3 Stag - awaiting gearbox rebuild

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