Kelly,
I didn’t think about it before, but you are right. On any permanent magnet motor, it will generate
electricity if it is spinning. Shorting
the leads would cause the motor to resist spinning.
That would be very easy for me to d, as I am turning in on through a double
pole relay. All I have to do is to
connect a ground to the normally closed contact on the relay.
Steve Brooks
-----Original
Message-----
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net]On Behalf
Of Kelly Troyer
Sent: Sunday, August 10, 2008 9:49
AM
To: Rotary motors in aircraft
Subject: [FlyRotary] 2nd flight on
the new cooling system
Steve,
I believe it was Lynn Hanover that said if you connect the power leads
(+ & - )
together when fan is not powered that it will not freewheel in flight.
Jump
in here Lynn and give us one of your sketches on how to wire it
so as not to
accidentally switch B+ (12 volts) to ground !!.........
--
Kelly Troyer
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold
--------------
Original message from "Steve Brooks" <cozy4pilot@gmail.com>: --------------
George,
The cooling fan has some
resistance when the power is off, and while I don’t know for sure, I doubt that
it spins when the power is off. Form a
longevity perspective of the bearings, I hope that it does not.
Regards,
Steve Brooks
-----Original Message-----
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net]On Behalf
Of George Lendich
Sent: Saturday, August 09, 2008
5:47 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: 2nd
flight on the new cooling system
Steve,
Does the cooling fan spin freely when turned off or does it remain
static.
Those temps are much better.
George ( down under)
I took the Cozy up this
morning for the 2nd flight on the new cooling system. The OAT was 3 or 4 degrees warmer than the
first flight, as it was 79 F when I took off.
This time, I turned the
cooling fan on while I was taxiing out to the runway. After the taxi and
pre-flight checks, the oil was 135 F and the coolant was still reading pretty
low. Maybe 115 to 120 or so. It is a little hard to read the analog gauge
down on the low end of the scale.
I took off and climbed up
to about 1300 FT AGL, at which time I pulled the throttle back some and
continued a cruise climb. The coolant
was showing about 190F, and I didn’t think to check the oil temperature. Oil temperature has not been my issue. It has always been the coolant. The coolant temperature did still increase a
little, even at the reduced power, but just up to 200 F. I was close to a low cloud layer at about
1800 AGL, so I throttle back some more and dropped the nose to level
flight. I also turned off the cooling
fan to see what the temperature would do on it’s own. The temperature steadily dropped to about 180 degrees within just
a few minutes, and then stabilized there.
I cruised around for a
little while, flew over my house and circled it once, and then headed back to
the airport. With the low cloud layer
that had moved in, I really didn’t know if it was going to clear out or get
thicker, so I flew the 5 minutes back to the airport, and made a normal
landing. As I was ready to throttle
back to descend about 800 feet to pattern altitude, and quick check of the
coolant temperature showed about 160 degrees.
Not bad at all, although I was probably flying at about 60% power. Still, it would have not been nearly that
low before the new cooling system.
Once I landed and was
clearing the runway, I checked the temperatures again, and the coolant was less
then 140 degrees after the glide in to land.
Since I planned to wash the plane, and sometimes it starts hard after
getting heat soaked sitting after a run, I turned on the cooling fan while a
taxied over to the where the wash area is.
After washing the plane, it started up pretty easily, so I guess that
worked out also.
So far so good. I like what I see so far on the radiator,
and the cooling fan definitely gives me a lot more options.
Steve Brooks
Cozy N75CZ
13B turbo to read the an