Spal FAN-PWM electric fan controller

[Ace in the hole]

Any one have any experience with a Spal FAN-PWM contrtoller. They are a little more pricey than others but I like the variable speed control. Just wanted to see if anyone has used it and what their thoughts are. I am thinking of using it with a chrysler jeep fan from this thread- http://67-72chevytrucks.com/vboard/s...d.php?t=254617

http://www.spalusa.com/

[Ace in the hole]

nobody has tried one of these?

[SactoJim]

Here's mine.

Running two junk yard fans from a Merc Sable. You might go ahead and get their sensor. I'm having problems getting mine to kick on in high mode. I called their tech line (very helpfull) and they said that sensors are typically the problem.

either way, I have an overide switch in the truck.

[Ace in the hole]

Thanks for the reply, you have a great looking set up from what I can see.

[72 longhorn BB]

IMO - I would keep it simple.

Why? - most aftermarket electronics are not tested as tough or made as durable as OEM electronic parts.

Specifically - I know the guy who developed chrysler solid state relays (SSR's), and man has he been busy with warranty concerns on SSR's.

These are the relays that are PWMed by the engine controller to vary the fan motor speed.

What a headache for the company.

In principle, they are supposed to work fine, but the predominant failure mode found over - and - over again is that they are designed with tool little ability to keep themselves cool.

Therefore, when they are being PWMed for lower voltage output, they make ALOT of heat.

In that mode, the die on the SSR gets too hot, and over time the wire bonds on the internal chip get weaker, and at one point they will reach a temp that either melts the internal wire bonds open, or melts them so they cause a shorted (always on) condition.

OEM's pay a decent price per each because of the testing we make the supplier do (i guess in this case it was not enough testing), but aftermarket electronics are not driven to do so.

Therfore, their quality and durability has always been less than OEM electronics, IMO.

Keep it simple, or if you are h e ll bent on doing this project for the challenge, heat sink the living snot out of the PWM module, and keep an extra PWM module (SSR) behind the back seat, so you don't get stuck.

Just my opinion

[Ace in the hole]

Your concerns have merit. Every electronic component will eventually fail, nothing lasts forever and after market parts can be more or less susceptible to failure. Depends on the company and where the part is made. Spal's controller looks like it has a pretty good heat sink on it already. I can think of a simple solution to a worry about being stranded though, a simple toggle switch to bypass the controller in the event of controller failure and feed strait 12v power to the fan and let it run wide open until you can replace or repair the problem.

The simplest thing to do in an electric fan conversion is to let it run all the time. You would still need a relay controlled from the ignition circ. to run the fan. I just like the idea of not having the fan run at 100% all the time when it's not needed and I'm not sure how loud it would be at full speed but I would think it would be loud enough to be noticable.