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Old 06-18-2006, 05:01 PM
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Originally Posted by rapsag
Got a relay, 30 amp. (no hang up tab was available). There are 4 terminals.
Correct me if I am wrong:

1:Terminals #85 and #86 are the coil terminals and polarity is not an issue?

Should I put a smaller fuse in the battery side lead to the coil?

Just substitute "temp sender for "Ground" in your case..Polarity is NOT an issue..and the fused side of the coil, need only be, 1 amp..

2: Terminal #30 is the power in tab (battery side) and must be fuse linked
with say 25 amp fuse-link.
This will be the FAN side..Always leave the the center wiper as the chosen device, not power..that way things can't short to the normally closed tools..

3: Terminal 87 (which is turned 90 degrees from the other 3) is the power out
to the fan.
No this will be the linked power..

10 gauge wire on the high amp side.
On the FAN circuit both sides of the CONTACTS are high draw.....

And is 14 gauge OK on the low amp side as I have some available.
14 Ga on the CONTROL circuit side, there is no "Low draw" on the relay contacts both sides will draw about 30 amps.. (relay coil only, will draw about 1 amp...)

I plan to place the relay in the engine compartment as close as possible to the fan, so as to shorten the high amp wire length. Then will run the low amp switch wires from the dash. All will be routed away from the exhaust areas (no problem)
BOTH sides of the relay contacts will be high draw sides..battery and both sides must then be 10 gauge (at least to the point of the fan wires you need to cut and put on a terminal strip)

The LOW draw side will be the CONTROL wire side, (the coil)

Am ready to fly upon your approval or correction of the above.
Yes I am compulsive, but it pays. rap
Make those small corrections and use the diagram above and you'll be fine..

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