ProJunkRacing
1/2 ton status
go to carquest and ask for an sw514 switch i belive what i was going to use but just got mine on switches
CK5
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Thermostatic switch for electric fans?
- Thread starter sled_dog
- Start date
Are those switches rated to carry the current for a fan? If you have two fans, thats got to be at least 15A, maybe even twice that.
If it is rated for that kind of current, then it's a very good solution. Otherwise, it just requires a relay like everything else (and it's still a good solution).
If it is rated for that kind of current, then it's a very good solution. Otherwise, it just requires a relay like everything else (and it's still a good solution).
neverendingproject
1/2 ton status
No, I believe you still have to use a relay, but its a non hassle way of doing it. Im using a relay with mine. Plus, it keeps it all GM.
edit: its a one wire hookup, so you would have to use a relay.
edit: its a one wire hookup, so you would have to use a relay.
Boondocks
1/2 ton status
I run the electric version of this http://www.centechwire.com/catalog/accessories/fc2p.shtml in my Yota.
Expensive, but I didn't have a place to install another switch in the water passage and didn't want to install a probe in the hose.
Expensive, but I didn't have a place to install another switch in the water passage and didn't want to install a probe in the hose.
some fuel injection computers will also controal a fan then you can set the turn on temp to what ever you want in the chip
sled_dog
1 ton status
Blue85 said:
no. some of them come with relays, some have to activate relays.
85mudblazin
1/2 ton status
I run a $16 adjustable one from the parts store. It isnt rated for alot of amps to its wired into my wiring diagrahm with 2 70 amp relays.
It has the metal probe that goes into the radiator and can be adjusted from like 0-300 degrees.
Works very good for me.
It has the metal probe that goes into the radiator and can be adjusted from like 0-300 degrees.
Works very good for me.
I need to finish the Windstar install.Has anyone made there own? You could buy any temp sensor that screws into your engines head and build your own circuit around it. I think you could do it with an Op Amp, a voltage regulator, a transistor and a relay. Everything minus the sensor would probably cost less than $5.00, you could program it for whatever on and off temp you liked and it would be cleaner than the probe on the radiator.
I'm going to start working on the circuit. Let me know if there are any other features that would be nice on a fan controller.
I'm going to start working on the circuit. Let me know if there are any other features that would be nice on a fan controller.
neverendingproject
1/2 ton status
Kinda what I said in post 20.
Did you make your own circuit? I like the sensor in you link. I try to use weatherpack and metripack connectors wherever I can.
I just sketched a circuit that has adjustable on and off points and should work with most 2 terminal coolant sensors. I'm trying to think of other features that would be nice. Control 2 fans with different on temperatures? Ability to run the fan for a specified time after the vehicle is turned off? Anything else?
I just sketched a circuit that has adjustable on and off points and should work with most 2 terminal coolant sensors. I'm trying to think of other features that would be nice. Control 2 fans with different on temperatures? Ability to run the fan for a specified time after the vehicle is turned off? Anything else?
It should be easy to make this circuit like you said. The real beauty, though, would be to keep it high impedance and use your existing temperature sensor. If you have a temp gauge, you have a sender.
You might use a comparator instead of an op-amp and try to use components rated for high temperature.
You might use a comparator instead of an op-amp and try to use components rated for high temperature.
I was thinking of the TL072 Op Amp used as a compartaor. It is a dual Op Amp. One would be for the turn on temp and one for the turn off temp. If there were 2 fans with different turn on temps I'd use a triple Op Amp.
Using the existing vehicle sensor would make a clean install. It would be a little more difficult if the CTS was being used by an ECM. I think that's why some of the older Chevys had two temperature sensors. One for the ECM and one for the gauge.
TI's version of the TL072 is good to 85 C for the standard 125 C for the high temp. 85 C would be fine in the cab. Under the hood I'd use the 125 C version.
Using the existing vehicle sensor would make a clean install. It would be a little more difficult if the CTS was being used by an ECM. I think that's why some of the older Chevys had two temperature sensors. One for the ECM and one for the gauge.
TI's version of the TL072 is good to 85 C for the standard 125 C for the high temp. 85 C would be fine in the cab. Under the hood I'd use the 125 C version.
I'm very interested in seeing any circuits you draw up. Are you an electronics wiz? 'Cause now and again I think it would be easier to make a circuit for some things rather than buy it. Like, for instance, a 12V gel cell battery charger circuit, that would run off 120VAC and shut off when the battery was fully charged. I know they're semi-simple, 'cause the life safety guys at work use them from time to time, but I haven't been able to get my hands on one, yet. I work with line voltages all the time, but am a super novice when it comes to solid state stuff.
neverendingproject
1/2 ton status
I like electronics and can design simple things, but I wouldn't call myself a wiz. I agree that it is often easier to build a circuit instead of buy it. You can also build in cool features that you won't get with something you buy. Electronics are cheap so the cost savings is usually huge.
I'll try to draw up my fan controller and post a diagram early next week. I think I have a gel battery charger diagram somewhere. I'll look for that and post it too. Maybe an electronics diagram thread would be in order.
If you have an idea for another circuit let me know.
I'll try to draw up my fan controller and post a diagram early next week. I think I have a gel battery charger diagram somewhere. I'll look for that and post it too. Maybe an electronics diagram thread would be in order.
If you have an idea for another circuit let me know.
OK, heres one. At a gunshow I went to a few years back, these guys were selling little radio transmitters with a little microphone, and a capacitor (I think) to tune the frequency. Ans a little solidwire antenna. The whole thing snapped onto a 9V battery and the actual circuit board was ojnly as big as the top of the battery, approx 1/2" by 1". It was for hiding somewhere in a room, the mic would pick up sounds/conversation, and then send it out on an FM signal. A little 'bug'. I was intrigued, but they wanted $15 each, and I figured, hell there only a few components, I can make onemyself. But as I said, I'm no solid state wiz. Think you could make this circuit?
