Where did you put ur temp sensor for an electronic fan clutch?

Ken, this is not a back up fan, but a replacement fan that uses electronic
fan clutch.
It does perform well as it is a very well designed blade.
Go to our web site and see.

On Fri, Mar 6, 2020 at 3:11 PM Matt Colie via Gmclist <

> > FYI, if you have the fan control that uses a 3/8" NPT threaded-in probe
> rather than the push in capillary style probe, I found a less expensive
> > radiator hose adapter for the fan control sensor, $10 on Amazon. I
> ordered the 40 MM model and received it today. I'll need to drill out and
> > re-tap the 1/8" NPT to 3/8" NPT but several reviewers of the part have
> already successfully done this. It is called a "Dewhel Aluminum Black Water
> > Temp Meter Temperature Gauge Joint Pipe Radiator Sensor Adapter 40mm"
> >
> > I also spoke to Tom Pryor (the inventor of this wonderful device) about
> the trigger temperature to use for the fan control. He disagrees with
> > suggestions of the 160 degree F trigger ("the fan will fun
> continuously") and said he thinks 200 F is the way to go. I think I'll try
> 200 and see
> > what happens. Looks like I'll be watching my temperature gauge (it is a
> real gauge marked in degrees, not just colors or words) like a Hawk and
> > hitting the fan clutch override on switch if it runs too hot and the fan
> hasn't kicked on. After I get it all installed, I'll report back on how
> > all of this is working.
>
> Jess,
>
> Tom is probably correct. As I said, I have not run the experiment.
>
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
Tom is right if you take the temperature at the top of the engine at the water outlet. Otherwise you are headed for overheat when not rolling down the
highway. Think about it... 8)
--
Terry Kelpien

ASE Master Technician

73 Glacier 260

Smithfield, Va.
 
I followed Tom's instructions included with the Mercedes fan package and mounted the thermostatic switch provided in the package, which I bought from
Jim K, through the fins on the radiator above the outlet hose from the radiator. As I recall, the switch turns on at 205 and shuts off at 195. This
fan is great! Even at full speed it's much quieter than the OE fan. Thank you Tom!

I know Tom is working on an improved method of temperature control, but as a tinkerer and an EE I'm trying my own approach. I've used Auber PID
Programmable Temperature controllers in a few home brew applications so I decided to try one to control the fan. To monitor the radiator temp I'm
using a K type thermocouple mounted through the fins adjacent to the thermostatic switch. I've mounted a Solid State DC relay, controlled by the PID
controller in parallel with the thermostatic switch (belt and suspenders)so either can turn on the fan. My guess is the thermostatic switch will
never turn on with this approach, but .... Anyway, I too feel that the thermostatic switch turns on at too hot a temperature for all the reasons
others have stated. I decided to set the PID controller to start turning on the fan at a low speed at 160 and build to full speed by 180. Since it's
easy to change the PID controller settings, I'm going to see what happens with this setting. The GMC 49ers are having a rally next weekend in
Sacramento which will be my first test. Hopefully the COVID19 virus scare won't cause it to be cancelled.

--
Jack Christensen - K6ROW,
'76 Glenbrook/Clasco - "The Silver Bullet",
Sebastopol, CA
 
Anytime you are below the boiling point of 50/50 Elethylene Glychol & water
under 9 psi of pressure, you are not going to do damage to your engine. You
might damage your peace of mind, but that is about all. If the fan
immediately lowers the coolant temperature below the thermostatically
controlled set point and then turns off, it is doing what it's supposed to.
If the temp goes above the boiling point, then you would have to turn it on
sooner. That's the way I see it. Your vision might differ.
Jim Hupy
Salem, Oregon

On Fri, Mar 6, 2020, 4:59 PM Jack Christensen via Gmclist <

> I followed Tom's instructions included with the Mercedes fan package and
> mounted the thermostatic switch provided in the package, which I bought from
> Jim K, through the fins on the radiator above the outlet hose from the
> radiator. As I recall, the switch turns on at 205 and shuts off at 195.
> This
> fan is great! Even at full speed it's much quieter than the OE fan.
> Thank you Tom!
>
> I know Tom is working on an improved method of temperature control, but as
> a tinkerer and an EE I'm trying my own approach. I've used Auber PID
> Programmable Temperature controllers in a few home brew applications so I
> decided to try one to control the fan. To monitor the radiator temp I'm
> using a K type thermocouple mounted through the fins adjacent to the
> thermostatic switch. I've mounted a Solid State DC relay, controlled by
> the PID
> controller in parallel with the thermostatic switch (belt and
> suspenders)so either can turn on the fan. My guess is the thermostatic
> switch will
> never turn on with this approach, but .... Anyway, I too feel that the
> thermostatic switch turns on at too hot a temperature for all the reasons
> others have stated. I decided to set the PID controller to start turning
> on the fan at a low speed at 160 and build to full speed by 180. Since it's
> easy to change the PID controller settings, I'm going to see what happens
> with this setting. The GMC 49ers are having a rally next weekend in
> Sacramento which will be my first test. Hopefully the COVID19 virus scare
> won't cause it to be cancelled.
>
>
> --
> Jack Christensen - K6ROW,
> '76 Glenbrook/Clasco - "The Silver Bullet",
> Sebastopol, CA
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Lets look at what GM does and go to school on that as far a E fans control. (Here replaced with E clutch control.) They sample temp at the enginr
output. They set the fan ON usually about 15 degrees minimum above the stat rating. They set the fan OFF speed at least 10 degrees below the on point
to eliminate hysteresis. Some vehicles use one fan with multiple speeds, others use 2 either in stages or both on but with a turn on delay to be kind
to electrical systems. On mutispeed fans usually LOW engages with compressor, High above a certain high side pressure. On my C4 no fans come in with
AC unlit pressure goes high, then they both come on sequenced. Not sure on the E clutch how much power is transmitted when disengaged and if that is
enough for good AC, or if it needs to follow AC clutch engagement. This would be easier to control on later CCOT cycling systems, but may result in
the fan staying engaged as IIRC the engage is rapid and disengage takes a couple mins.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Bill,
The PID controller I'm using uses Pulse Width Modulation. It sends out a pulse every 2 seconds whose width (up to 2 seconds) depends mainly on how
far away from 160 degrees the water temp is. At 180 degrees the pulse will be 2 seconds wide and the fan actuator will be on 100%. With a PID
controller, there are other factors that come into play. I read some literature on how these type of fans are controlled and this seems to fit the
model.
--
Jack Christensen - K6ROW,
'76 Glenbrook/Clasco - "The Silver Bullet",
Sebastopol, CA
 
Well my name has emerged too many times, so I will have to offer my input.

Let's us go back to the Thermal spring in our old Viscous clutches....What
activated it, heat from the radiator, yes?

The idiot light and subsequent temperature gauges were connected to thermal
output devices (sensors) in the engine........ BUT DID NOT CONTROL THE FAN
ACTUATION, YES?

With that as the foundation for our thoughts to activate the Electronic
Viscous Fan clutch, it makes perfect sense that we really want this new
device to act like our old Fan clutch, just more reliably, with a dash
switch over ride, and measure coolant rather than hot air. We also get
the added benefit of double the air flow (CFM).

That said, CURRENTLY when the controller sees 210 degrees coolant output
from the radiator it activates the fan. The fan will remain activated
until it sees a 15 degree drop (195).

Coolant in the radiator will fluctuate between those two temperature
regardless of the temperature gage on the dash! Just like the old days,
yes?
Thing is, we don't really know the activation points of the old bimetal
spring....... it turned on and turned off. When the dash light turned on
or the dash gauge went above 212 we changed out the Fan Clutch. We
operated, fat, dumb, but happy! Based on all my investigations and
discussions with Dick Patterson we are not going to degrade the life of any
engine. Now we just have more input data and can tweak if and when
required.

Thats my story, but I am willing to listen to any and all input.

Tom Pryor
4188 Limerick Dr
Lake Wales, Fl 33859
Cell 248 470 9186

1977 23'B named "CASPER", HARDLY ORIGINAL, (455 EFI) (Pwr. Drive)
(tailgate) (rear bunk beds)
(Webasto petrol boiler) (MB Elect fan clutch) (Brake reaction arms) BUT
STILL A WORK IN PROGRESS!

ReplyForward
 
The question becomes for the PWM controllers, what's the optimum repetition rate for pulses? I gather both extremes are being investigated. I lean
toward the two seconds, but purely on instinct.
Also, how accurate is stuffing the sensor in the radiator fins vs in the hose?
Anybody using the tach output for anything?

--johnny

--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
The PWM controller on mine (home brew electronic fan clutch setup) acts more as an on off switch as I'd guess the pulses are much too fast for the
viscous valve in the clutch. The PWM controller was built for an electric fan so in it's intended application I'm sure it works correctly. If you have
a method to slow down the pulses Johnny, I'd love to know how to do it. The OEM's manage it through their PCM's I'd imagine. Being able to ramp up the
speed as temperature requires would be great. It would probably all but eliminate full on fan engagement and the accompanying noise.
As for sensor location, I used the radiator fins rather than direct H2O sensing. My research as well as the PWM's manufacture's suggestions recommend
that location. I don't see an issue with either location as the activate temps are adjustable and can be easily set with a known good temperature
gauge. Keeping the temps in check is what it's all about and with the T stat working correctly that should regulate the actual engine temps
accordingly.
And the tach output wires are in free air just enjoying the ride.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM
 
> Bill,
> The PID controller I'm using uses Pulse Width Modulation. It sends out a pulse every 2 seconds whose width (up to 2 seconds) depends mainly on
> how far away from 160 degrees the water temp is. At 180 degrees the pulse will be 2 seconds wide and the fan actuator will be on 100%. With a PID
> controller, there are other factors that come into play. I read some literature on how these type of fans are controlled and this seems to fit the
> model.

I'd sure like to know which PID you are using. It sounds like it might be just the ticket for my application.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM
 
Jack,

While I like the idea of a full PID control, I noticed that the number you posted needs service lever AC power.

Did you all ready have an inverter on line? (I am guessing you don't restrict travel to where your shore power cord can reach.)
I know it does not need a lot of power, but that just adds a possible failure to the system.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
I hope to report success with my PID controller management of the Mercedes fan after my upcoming drive the GMC 49er's rally in Sacramento. Hopefully
I won't return with my tail between my legs.

There seems to be a lot of interest in the controller. FYI, it's a Auber Instruments SYL-1612B unit designed for use at either 12 or 24 VDC combined
with the Auber SRDA100 solid state relay. According to the spec sheet the power draw is less than 2 watts. I've used their AC units in a couple of
other applications and they've worked just fine. WWW.AUBERINS.COM. If there's interest in how these PID controllers work, just search on-line for
PID controllers and you'll find more than you want to know. They're really marvelous (and inexpensive) little devices and lots of companies make them.
--
Jack Christensen - K6ROW,
'76 Glenbrook/Clasco - "The Silver Bullet",
Sebastopol, CA
 
PWM rate is usually far above the response rate of whatever you are controlling. It is used as a simple way for a digital controller to supply an analog voltage. A low duty cycle looks like a low voltage while a high duty cycle looks like a high voltage. The fan or clutch or whatever is never expected to be able to cycle at the PWM frequency, rather the RMS voltage of the waveform looks like a variable DC voltage to the device being controlled,

Note that some devices, like most air solenoids do not work well with a PWM signal because they will do nothing until the voltage reaches the pull in voltage, upon which they will fully open and latch there until the voltage drops below the drop out voltage. There is voltage hysteresis that prevents rapid cycling between open and closed.

The fan clutch may work with PWM, but testing would have to be done. A variable power supply would suffice.
Just power the clutch and vary the voltage, see if the clutch engagement is dependent upon voltage or if there is a sudden change at a specific voltage
________________________________
From: Gmclist on behalf of Hal StClair via Gmclist
Sent: Tuesday, March 10, 2020 1:43 PM
To: gmclist
Cc: Hal StClair
Subject: Re: [GMCnet] Where did you put ur temp sensor for an electronic fan clutch?

The PWM controller on mine (home brew electronic fan clutch setup) acts more as an on off switch as I'd guess the pulses are much too fast for the
viscous valve in the clutch. The PWM controller was built for an electric fan so in it's intended application I'm sure it works correctly. If you have
a method to slow down the pulses Johnny, I'd love to know how to do it. The OEM's manage it through their PCM's I'd imagine. Being able to ramp up the
speed as temperature requires would be great. It would probably all but eliminate full on fan engagement and the accompanying noise.
As for sensor location, I used the radiator fins rather than direct H2O sensing. My research as well as the PWM's manufacture's suggestions recommend
that location. I don't see an issue with either location as the activate temps are adjustable and can be easily set with a known good temperature
gauge. Keeping the temps in check is what it's all about and with the T stat working correctly that should regulate the actual engine temps
accordingly.
And the tach output wires are in free air just enjoying the ride.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM

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