pmw fan controllers

[rickpaw]

Painless F5 controller has pwm control, and can control 2 fans. Kind of spendy @ almost $300 though

http://www.jegs.com/i/Painless-Perfo...30142/10002/-1

http://painlessperformance.shptron.c...-metric-sensor

[scott_fx]

wow these things get expensive! these could be built for half the price if you know how to do a little coding and are handy with a soldering iron.

[sjaroslo]

How important does everyone feel it is to be able to turn the fans completely off above a certain highway speed? I see that now as the main difference between the Painless F5 and the DCC approach; the Painless can do it, the DCC does not. On the one hand, that used to drive me crazy with my previous car. Because of the way the electronics were set up, once the fan kicked on but the temperature reached an equilibrium, the fan would never turn off on the highway, so the ability to decode the VSS signal and turn everything off after 5 seconds above an adjustable speed sounds very appealing.

On the other hand, I am pretty sure that the DCC is a top quality product, it brings an endorsement from John Parsons (which carries a lot of weight in my mind), and I have a vaporworx set up for the fuel pump that also will use DCC stuff, so there is precedent....

I think I also like the DCC approach of putting a probe in the radiator, rather than screwing in to the port on the head, but I'm not sure if I like it because I think that it is more technically accurate, or that it simply avoids having to come up with another "tee" fitting to be able to drive both the controller AND my water temp gauge; the port on the other head will use the factory sender to feed the ECU; not sure if the signal can be split electrically or whether one would need two senders (or three, total). I guess I have the same issue with the VSS--I need to feed the signal from the trans to the ECU, but there is a VSS output on the bulkhead connector, but I was going to use that to drive my speedometer.... Not sure that it can also be routed to the pwm controller...

*Sigh*

[scott_fx]

i can't imagine there not being enough current for multiple taps off the sensor if it's a digital output. The current draw for microcontrollers are very low.
if it's analog signal (0-5v) then i can see this as being an issue.

How important does everyone feel it is to be able to turn the fans completely off above a certain highway speed? I see that now as the main difference between the Painless F5 and the DCC approach; the Painless can do it, the DCC does not. On the one hand, that used to drive me crazy with my previous car. Because of the way the electronics were set up, once the fan kicked on but the temperature reached an equilibrium, the fan would never turn off on the highway, so the ability to decode the VSS signal and turn everything off after 5 seconds above an adjustable speed sounds very appealing.

On the other hand, I am pretty sure that the DCC is a top quality product, it brings an endorsement from John Parsons (which carries a lot of weight in my mind), and I have a vaporworx set up for the fuel pump that also will use DCC stuff, so there is precedent....

I think I also like the DCC approach of putting a probe in the radiator, rather than screwing in to the port on the head, but I'm not sure if I like it because I think that it is more technically accurate, or that it simply avoids having to come up with another "tee" fitting to be able to drive both the controller AND my water temp gauge; the port on the other head will use the factory sender to feed the ECU; not sure if the signal can be split electrically or whether one would need two senders (or three, total). I guess I have the same issue with the VSS--I need to feed the signal from the trans to the ECU, but there is a VSS output on the bulkhead connector, but I was going to use that to drive my speedometer.... Not sure that it can also be routed to the pwm controller...

*Sigh*

[scott_fx]

asked around a bit and this is the response i got concerning multiple taps off of any signal wire:

That's called "fanout" and yes, it is a concern in digital circuits as well. Ideally you'd check the datasheet for the component, but that might not be an easy option with proprietary or obfuscated hardware.

If you at least know the impedance of the device you are attaching, you could make an educated guess. But the best solution (that i can think of) would be to use a jfet op-amp in voltage-follower configuration as a buffer.

[sjaroslo]

asked around a bit and this is the response i got concerning multiple taps off of any signal wire:

Thanks for the info. Not that a lick of it makes any sense to me, but the effort is appreciated nonetheless :-)

[scott_fx]

pretty much they are saying you need to 'amplify' the signal if you're going to tap off of it multiple times.

[parsonsj]

Going back to the question about the fans running while the vehicle is cruising: I think it can be overcome by getting a thermostat that opens below the temperature that the fans kick in. If the radiator is correctly sized, the coolant temp should drop to the thermostat temperature, and the fans won't run.

That works fine for the coolant temperature bit, but the A/C makes it trickier. In that case the DCC controller will turn on the fans when it senses the A/C running, even if the vehicle is cruising. I don't know about the Painless part, but I'll bet it will do the same. IOW, most of these controllers just have a simple A/C override without taking vehicle speed into account.

[Samckitt]

John Parsons, you use the factory GM setup or going aftermarket?

[sjaroslo]

That works fine for the coolant temperature bit, but the A/C makes it trickier. In that case the DCC controller will turn on the fans when it senses the A/C running, even if the vehicle is cruising. I don't know about the Painless part, but I'll bet it will do the same. IOW, most of these controllers just have a simple A/C override without taking vehicle speed into account.

Actually, John, it looks like they covered this. From the F5 manual:

"Note:If vehicle has the A/C compressor running but is also traveling above the vehicle speed set point the F5 controller will not engage the cooling fan. This is because when a vehicle is traveling at highway speeds the air moving across the A/C condenser should be adequate for the heat transfer required by the condenser."

[parsonsj]

Actually, John, it looks like they covered this...

Cool! That's a big plus, and makes the Painless controller the better product.

John Parsons, you use the factory GM setup or going aftermarket?

I'm going to use the GM E67. I've got the A/C refrigerant sensor and pigtail, and two C6 fan controllers. I'm working with Vintage Air on integrating the GM sensor into their trinary switch. More to come, but I think I've got all the bases covered.

[andrewb70]

....

I'm going to use the GM E67. I've got the A/C refrigerant sensor and pigtail, and two C6 fan controllers. I'm working with Vintage Air on integrating the GM sensor into their trinary switch. More to come, but I think I've got all the bases covered.

Need more tech on this.

I have the E67, but it would be great if my dual Spal fans were turned on gently and in sequence. How do you integrate the C6 fan controllers with the E67 ECU? I don't have A/C, so I would think this makes it easier.

Andrew

[parsonsj]

How do you integrate the C6 fan controllers with the E67 ECU? I don't have A/C, so I would think this makes it easier.

It's pretty simple, really. Just add the pwm wire (J3-54, iirc) to the ECM, snag a C6 fan controller ($89 on Amazon), do some basic wiring, and have your E67 switched to PWM fan control (instead of discrete). Most tuners can do this. The guy who can set you up with a kit is Bill at BP Automotive.

[sjaroslo]

How does one know if one is using an "E67" controller?

[parsonsj]

Steve, I'm pretty sure all the GMPP crate offerings use the E67.

[GNon18s]

This reminds me, I ordered the Painless F5 controller six weeks ago and it still hasn't shown up. Hmm, guess I better call about that Monday.

[sjaroslo]

This reminds me, I ordered the Painless F5 controller six weeks ago and it still hasn't shown up. Hmm, guess I better call about that Monday.

Not a good sign!