How does this get wired?
New electric fan 1 blue 1 black wire
I guess the blue is hot? black is ground?

Relay
1 Terminal for fan etc..Blue wire?
2 " for ground , black wire from fan?
3 " for a switch (under or in dash)
4 " power source 12v relay or fuse panel?

I want to be able to turn it on/off at switch.
Thanks

Do you want the switch to switch +12v to the relay, or ground to the relay? Depending on what you want you wire it one of two ways.

With the switch sending +12v to the relay you do it as follows:
85- ground (not the one to the fan, just a ground in general)
86- switched +12v from the switch to turn the fan on
30- constant +12v from a reliable source, large awg wire (enough to supply sufficient juice to fan)
87- +12v to fan... again, with a sufficient awg wire


With the switch sending a ground to the relay, wire as follows:
85- switched ground from switch to turn fan on
86- constant +12v (easily jumped from term. 30)
30- constant +12v from reliable source, again large awg wire
87- +12v to fan... again, sufficient awg wire


As for which wire is positive on the fan, that's easy to figure it out. Hold one to ground and the other to +12v momentarily... if the fan turns the correct direction then you have it right, if it spins opposite of desired direction than switch the ground and +12v

Thanks Darrah
I think I have the 30 and 87 switched
I will check it tomorrow.
How are things with you?
Going to make Hooters in May?
Thanks again