fan switch= really hot

[sidewayzisbest]

Well i have my e-fan wired this way; starting to get really hot: have the power wire going to the solinoid & then to a switch and the switch is grounded....it has a light in the switch but still dont think it should get that hot.....right now i have no relay cuz it the one messed up if that could be it maybe?(25 autozone..mark 8 fan) up so i switched it to just the switch till i can get a bosh 75amp

thanks

 

[jrichker]

You have miswired something. Can you draw a picture of your current wiring?

 

[sidewayzisbest]

You have miswired something. Can you draw a picture of your current wiring?

sure i prob have.....im not very good at wiriing

but went in paint and came up with this thanks for the help

 

[sidewayzisbest]

well lets try again

 

[Idwitheld-1`]

Its wired "right". Except that you're pumping a huge current through that swithch and its heating up. It will fail. Very few swithces can handle 20-70 amps....and it would be gigantic if it did.

 

[sidewayzisbest]

umm what should i change about it

 

[blkstangman88]

go to radioshack or somthing and ask the guy there u need a switch that can carry more power.

 

[87TTopGT]

Mine is the same way- wires on switch are smaller guage than wires from fan, VERY hot. Took my ashtray out and ran switch in there, plenty of room when I find a bigger switch.

 

[sidewayzisbest]

any way to wire differnet so i dont have to get a bigger switch?

 

[Idwitheld-1`]

What you need is a power relay. The relay needs to be sized to handle your fan load. Typical sizing is a minimum of 125% of load.

 

[hllon4whls]

See if you can understand this. The switch can be as small as you want it in this diagram. The relay carries all the heavy current. You can get a relay from any autoparts store for about $12 with a harness (4 wires). The lighting relays work good and they are rated for 30 amps. You are going to need some 10-12 gauge wire if you keep the runs short (smaller number=bigger wire).

Use some different colors other than all red so you can see what the hell is going where.

 

[sidewayzisbest]

thanks , what size fuse do you have going to the solineod? also anything to use to go into the fuse box i have my tach already in there wondering if i could just splic in the tach maybe? or use maybe the mass air well tahtswhat i used before the relay craped on me

 

[hllon4whls]

a 30 amp fuse will be about right for most fan applications. You can use just about anything in the fuse box because the relay coil will only draw about 1/4 amp. You should still fuse that line comming out of the fuse box somehow with like a 1 amp fuse.

 

[HISSIN50]

Hllon, from what i could gather from Sidewayz's first post, your diagram is right on! (i could not decipher what he was talkin about with the Mark VIII part).

i will toss out that a lighted rocker switch will get quite hot, even when feeding a relay ( a 250mA draw, plus lighting the switch, as you said).....but i would get that relay in ASAP.
i would perhaps be more concerned with how hot the wiring is getting, if you did not use hog wire. and make sure to booger a fuse into your wiring for now. otherwise, a fire could be next....good luck.

 

[sidewayzisbest]

thanks hllon

got another question i cant remember how i had my relay hooked up when i had ..

i figure

(85)(to ground)= ground
(86)(to switchin means)= would that be either when the key is on or to the fan?
(30/51)(fused from battery)= im going to guess to the soleniod
(87&87)(Power to lamps)= would that be to the when key is on or to the fan?

thanks for all the help everyone

 

[Michael Yount]

Many of the larger fans will cook a 30A during extended use or during the initial start up current spike (as much as 2 to 3 times the steady state draw for a fraction of a second when power hits the circuit).

Try this controller - renders switches and relays obsolete. www.dccontrol.com

 

[Idwitheld-1`]

Many of the larger fans will cook a 30A during extended use or during the initial start up current spike (as much as 2 to 3 times the steady state draw for a fraction of a second when power hits the circuit).

Try this controller - renders switches and relays obsolete. www.dccontrol.com

not to split hairs but it is a switch. Its just solid-state (probably PWM modulation with FET or bipolar drivers).

I am very impressed with everything I have read on this product. I too will migrate this route soon.

 

[HISSIN50]

thanks hllon

got another question i cant remember how i had my relay hooked up when i had ..

i figure

(85)(to ground)= ground
(86)(to switchin means)= would that be either when the key is on or to the fan?
(30/51)(fused from battery)= im going to guess to the soleniod
(87&87)(Power to lamps)= would that be to the when key is on or to the fan?

thanks for all the help everyone

ok, sounds like you are using a Blazer driving light relay....that will work, but not the greatest choice.....
86 will actually turn the fan on, when you provide 12 volts to it. so choose a source.....this wire should draw less than .5 amps, so dont sweat it too much (now that you are using a relay, the demand on your switch, and so on, has diminished).

87 is output for the fan (run a good sized wire from 87 to the + connection for the fan).
you only need to use one terminal 87. the driving light relays dont have a NC terminal in the middle, but rather two NO terminal output terminals (87 and 87).

good luck.

BTW, as Michael said, draw at start up can be gross, so make sure to turn the fan off before starting. i cant remember if you were gonna get a a fan switch/controller for it, but it is a real nice idea (be it Michael's nice one, or something pieced together).

BTW ID, i have no idea what you were talkin about.

 

[Michael Yount]

id - I suppose it could be semantics, but there's no way I'd describe something which infinitely varies the CURRENT to a motor to infinitely vary the motor rpm in order to maintain a set temperature point as simply "a switch". The toggle you buy at WalMart - that's "a switch". The term switch is pretty universally accepted as a device which allows a connection to either be made, or not made. Binary. On or off. This piece couldn't be described that way, at least not reasonably.

 

[sidewayzisbest]

oh uh.........wired it up and i think i blew the relay.....

but the solineod sparked i think caused some problems.....im thinkin the fuse link for the fuel pump since its not priming and it looks to be cut into the wire i guess got cut being in there too tight but is there a way to figure if thats it or not.