PWM Fan controller - Need help/clarity on a purchase

stussy2870

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Guys, I'm looking to get a PWM Fan controller for the contour fans currently installed. The PO installed these and the wiring is a mess. Im cleaning it all up and what to get a standalone fan controller.

Seems like Autocoolguy's controllers are hard to beat but was hoping for a cheaper option.. I read somewhere that the Contour fans spike at nearly 120A!! Knowing that its damn near impossible to find a controller for under 250.00..

Anyone have any suggestions - would like to buy what i need asap..
 
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Steel1

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If you're just looking for a decent variable speed fan controller I've had good luck with the Flexalite VSC33054 with
my dual Interpid fans. I think Dakota makes a good one as well and there's some mystery guy that no one can seem to contact who
supposedly makes a quality controller.
Now if you're looking for a PWM controller to work with a Megasquirt or similar ecu, I haven't crossed that bridge yet.
 

CarMichael Angelo

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If you have a mega squirt, all you need is a solid state relay, use the right output, and find somebody who can program a pwm duty cycle on that output.

I have that setup. All it took was a 40.00 relay, and Steve.
HLAh41773001_w.jpg
 

Blown88GT

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Guys, I'm looking to get a PWM Fan controller for the contour fans currently installed. The PO installed these and the wiring is a mess. Im cleaning it all up and what to get a standalone fan controller.

Seems like Autocoolguy's controllers are hard to beat but was hoping for a cheaper option.. I read somewhere that the Contour fans spike at nearly 120A!! Knowing that its damn near impossible to find a controller for under 250.00..

Anyone have any suggestions - would like to buy what i need asap..
I assume "spiking" is referring to starting current.
I don't know where you heard that, but it's wrong.
The Lincoln Mark VIII fan starting current is 105A.
The dual Contour fans are far less, no more than 60A.

The DCC FK-45 will control any of these. It's $150.
 

Blown88GT

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stussy2870

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I assume "spiking" is referring to starting current.
I don't know where you heard that, but it's wrong.
The Lincoln Mark VIII fan starting current is 105A.
The dual Contour fans are far less, no more than 60A.

The DCC FK-45 will control any of these. It's $150.


Wow.. Thats what i needed to hear.. Thanks so much. I was leaning that way. Is the Derale really a POS? looks nice.. but man that thing gets sh1t for reviews..

Thanks for all the replys!!
 

bwest

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Can confirm - Contour's use 2 different relay circuits for hi/low. And they pull an insane amount of air. I've also owned 2 SVT contours.

The fans work wonders on a retrofit too. When controlled correctly. A 2 stage (hi/lo) controller would be pretty adequate - It was a rare day for them to switch onto high unless in stop/go traffic + A/C running on a hot day. Those engine compartments were also packed super tight - much tighter than any v8 mustang.

I ran them in a Supra I had years ago and used a PWM controller by Spal (I don't know if it's still in production). Once I got it figured out/setup correctly, i had 1 fan acting as a primary (50-90%) and then when it hit the hot threshold, both fans would kick on at 100%. This was rare. The Supra had an 85a alternator and without a PWM controller, the contour fans were too much (on/off) with the lights running.

TL;DR - they are fantastic fans that draw some serious power. Set up right, they will work as good/better than the stock 2spd fan on the SN95. Get a PWM controller that triggers from an inblock sensor. Otherwise you'll be redoing it again in the future.
 

Ragtop50

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I have a Flex-a-lite 31165 and have been very happy with it. Great features and PWM functionality.
You can even connect a switch for manual override.
 

Blown88GT

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Wow.. Thats what i needed to hear.. Thanks so much. I was leaning that way. Is the Derale really a POS? looks nice.. but man that thing gets sh1t for reviews..
...
The Derale is the DCC design. His patent number is printed on it.
Better to deal with him directly but you have to be patient. It's a 1-man company & he gets very busy in the summer.
Full disclosure: I am DCC customer #1. If it had a S/N, it would be #2.

BTW, motors have a starting current 3-5 times running current. The high starting current is one way that kills the relay contacts. The Bosch 70A relay is rated for motor loads. The 70A rating is the running current rating. It will start the 105A Mark VIII fan. Also, when the fan turns off, the collapsing magnetic field of the motor creates a large reverse voltage spike which will arc across the relay contacts, so a freewheeling diode is recommended to suppress the spike. Ford uses one on the A/C compressor clutch.
 

Noobz347

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Guys, I'm looking to get a PWM Fan controller for the contour fans currently installed.


This truly messed me up for a minute. The controller you are looking for is not Pulse Width Modulated or a "PWM Controller". PWM suggests a 3-phase, brushless motor (cool idea now that I'm thinking about it). Having said that, there are controllers that use a PWM modulator as input to dictate voltage to a brushed motor but that is in the place of a variable resistor that would likely cook under load with decent current.

I realize it wasn't the point of your post but wanted to clarify that you can't just send a PWM signal to a set of Contour (or otherwise) cooling fans. Well technically, you could but it would also require an Electronic Speed Control (ESC).
 

Blown88GT

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This truly messed me up for a minute. The controller you are looking for is not Pulse Width Modulated or a "PWM Controller". PWM suggests a 3-phase, brushless motor (cool idea now that I'm thinking about it). Having said that, there are controllers that use a PWM modulator as input to dictate voltage to a brushed motor but that is in the place of a variable resistor that would likely cook under load with decent current.

I realize it wasn't the point of your post but wanted to clarify that you can't just send a PWM signal to a set of Contour (or otherwise) cooling fans. Well technically, you could but it would also require an Electronic Speed Control (ESC).
I think you are confused. The unit described in the patent is running my dual Contour fans; it used to run my Mark VIII fan.
Read the patent for a Pulse Width Modulator
 

Noobz347

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I think you are confused. The unit described in the patent is running my dual Contour fans; it used to run my Mark VIII fan.
Read the patent for a Pulse Width Modulator


The Link Above said:
The present invention encompasses a high efficiency pulse width modulator comprising: a variable duty cycle oscillator for receiving an input signal and providing a low level switching signal

Having said that, there are controllers that use a PWM modulator as input to dictate voltage to a brushed motor


Not confused. The one you linked used a PWM signal generator as a signal input like the ones I described.


Voltage on a 3-phase PWM controlled fan would be constant. Your controller varies the voltage to the fan.
 
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Noobz347

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20200616_183713.jpg

20200616_183707.jpg


For the sake of comparison:

Pictured above is a Pulse Width Modulator (PWM). It has a power and ground and two contacts that feed a conditioned signal to a module within a Pulse Width Modulated Fan that dictates fan frequency through a digital pulse.

Our cooling fans are the regular style. At 14 volts you get a certain speed and can vary that speed by changing the voltage.

These new-fangled controllers do something a little different. They convert the temperature sensor readings to a digital signal through a PWM. The controller receives it and uses it as the input to vary the voltage at the fan.




I stayed at a Holiday Inn Express last night. :shrug:


A comparison pinout between 3-pin and 4-pin PWM:
1592347616896.png


I don't possess a contour fan to check but my DCController is often used to run Taurus fans is for the type on the left (brushed style motor).
 

stasha

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OK, I've read this thread every day, and after about 30 seconds, my mind goes to blah blah blah.

Might as well get something out of it, so QUESTIONS:
1. What the heck is PWM -- I can read the words, but WHY would anyone want a PWM?
2. Is PWM what gives a "slow start" to a fan?
3. How do you know if you have a brushless fan motor?
4. When would I want PWM?
5. How do I know if I have a PWM?
6. Is the Dakota Digital PAC-2700 fan controller a PWM?

Thanks.
 

Blown88GT

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OK, I've read this thread every day, and after about 30 seconds, my mind goes to blah blah blah.

Might as well get something out of it, so QUESTIONS:
1. What the heck is PWM -- I can read the words, but WHY would anyone want a PWM?
2. Is PWM what gives a "slow start" to a fan?
3. How do you know if you have a brushless fan motor?
4. When would I want PWM?
5. How do I know if I have a PWM?
6. Is the Dakota Digital PAC-2700 fan controller a PWM?

Thanks.
It doesn't vary the voltage, it varies the duty cycle of the voltage, i.e. square wave, 0-12V
1. PWM = Pulse Width Modulation as in the sentence above. Why? Variable speed control.
2. Not necessarily, but is usually part of the design of a PWM controller. It is referred to as a "soft start".
3. Google the part number.
There are 4 main types of DC motors:
  • Permanent Magnet DC Motors. The permanent magnet motor uses a permanent magnet to create field flux. ...
  • Series DC Motors. In a series DC motor, the field is wound with a few turns of a large wire carrying the full armature current. ...
  • Shunt DC Motors. ...
  • Compound DC Motors.
4. When you want to vary the speed according to temperature.
5. Don't know what you know or don't know.
6. If it's variable speed, it's PWM. Variable as in ~10 rpm to max rpm & anywhere in between.

BTW#1, this is not an online class in electrical engineering even if I am qualified to teach it, which I am (LOL).
Google "PWM dc electric motor", then you can teach the class.
1st hit on Google:

BTW#2 Electric cars use AC motors. The battery voltage must be converted from DC to AC. Speed control is not PWM.
The two primary ways to control the speed of a single-phase AC motor is to either change the frequency of the line voltage the motor sees or by changing the voltage seen by the motor, thereby changing the rotational speed of the motor.
Electric cars & all industrial equipment use 3-phase electric motors. Lesson #2, some other time.

BTW#3 Your alternator is a poly-phase (more than 3) generator. A motor can be a generator & a generator an become a motor. Electricity can create magnetism & conversely, magnetism can create electricity. High school physics.
 

jrichker

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OK, I've read this thread every day, and after about 30 seconds, my mind goes to blah blah blah.

Might as well get something out of it, so QUESTIONS:
1. What the heck is PWM -- I can read the words, but WHY would anyone want a PWM?
2. Is PWM what gives a "slow start" to a fan?
3. How do you know if you have a brushless fan motor?
4. When would I want PWM?
5. How do I know if I have a PWM?
6. Is the Dakota Digital PAC-2700 fan controller a PWM?

Thanks.
Pulse Width Modulation explanation
58887.gif


Starting a motor at 3 volts and then gradually increasing it to 12 volts draws much less current that a sudden application of 12 volts to the motor - hence the term soft start. The ability to run the motor at a variable speed makes it easier to keep engine coolant temperature in the desired range. There will be a minimum of coolant peaks and valleys, more of a constant coolant temperature.
 
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stasha

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Wow. Thanks to both replies.
I will have to read this again tomorrow.
I catch myself going "blah blah blah", meaning my brain must be shutting down.
Guess the square wave and duty cycle, and changing who sees the freq of the voltage -- etc, is hard to visualize what it means.
I'll try that google source.
(Took several physics courses, but back in the late 60s -- before they invented gravity.
 

General karthief

wonder how much it would cost to ship you a pair
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(Took several physics courses, but back in the late 60s -- before they invented gravity.

Wait, but you show your age as 39, or were you born in 39?