I second Al opinion on not using soldered Dsub
connectors. In my opinion crimped Dsub connectors are more professional
and potentially reliable. Soldered connections are more prone to
corrosion, cold solder joints, crystallizing and breakage from vibration.
I am not saying I do not have any solder joints in my airplane, but there are
none anywhere in the engine controller circuit. If you are looking for a
source for milled pins - Steinair.com, $25 /c for pins and sockets.
Crimped (milled) pins and sockets are much easier and IMO result in a more
professional installation.
Joe
----- Original Message -----
Sent: Sunday, October 08, 2006 10:31
AM
Subject: [FlyRotary] Re: Latest EC2
updates, Installation notes
Wendell;
If I were doing it
over, I’d use twisted conductor, shielded cable (ground shield at box).
I don’t know that it is needed, but it can help eliminate capacitance
coupling and RF interference. Inductive (magnetic) coupling could still
occur, so if you can separate them by 2-3 inches it would be good.
Electrical noise is a bit of a guessing game, so take this as one of the
guesses.
Another opinion:
I’d also replace all the solder socket plugs with the machined, plated, crimp
D-sub connectors. It’s faster, easier, more consistent, eliminates the
potential of flux induced corrosion, and gives you removable pins. I did a
careful soldering job, but used Radio Shack flux core solder; and on careful
examination of connectors done a few years ago there are signs of corrosion.
For thermocouple connections directly to the d-sub, it is necessary;
thermocouple leads do not ‘solder’ unless you use silver solder; which you
really can’t do on the d-sub plug without melting the plastic
carrier.
Just my
opinions.
Al (still fighting
noise issues and a bad thermocouple connection)
-----Original
Message----- From: Rotary
motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Wendell Voto Sent: Saturday, October 07, 2006 8:08
PM To: Rotary motors in
aircraft Subject: [FlyRotary]
Re: Latest EC2 updates, Installation notes
Would shielded
cables be okay to run close together in a fiberglass
aircraft?
-----
Original Message -----
Sent: Wednesday,
October 04, 2006 9:31 AM
Subject: [FlyRotary] Re:
Latest EC2 updates, Installation notes
While
trouble shooting Al Gietzen's EC2 engine controller problems, he mentioned
that he was seeing relatively large mixture changes when the
alternator was switched off and the battery voltage went low. The
mixture goes leaner with lower battery voltage because the
injectors take longer to open. It was well within the range
of the manual mixture control to correct but it got me to thinking about
adding battery voltage compensation to the EC2. This has been
done and all controllers shipped after 9-20-06 now incorporate this
feature. Not a freebie, but if anyone wants this incorporated into an
earlier EC2 it can be retrofitted.
The
other update is a rev limiter. It was easy to do so I went ahead and
added it. I haven't seen this as a priority because in our application if
you make use of it, it means that you need to be more concerned about the
pilot's health than the engine's (the prop has fallen off the
airplane). The default rev limit is 8000 rpm. If you want
something different, specify when ordering. (Also
retrofittable)
EC2 /
EM2 Installation Note.
This
only applies to EC2 engine controller installations combined with early
two-part EM2 engine monitors in canard aircraft where both units are
installed near the engine and have long wiring harnesses connecting them to
the EC2 front panel and EM2 display (a rare combination that may be unique
to Al's airplane). Have been working with Al for some time
searching for the cause of random MAP table and other EC2 parameter
corruption. I am now almost certain that the cause is noise coupling
from the EM2 display harness into the EC2 control panel harness. The
two harnesses were laced together in Al's installation. He
is in the process of separating them now (sympathies to Al, no
picnic). Needless to say at this point, never run these
two harnesses together and separate them as far as practical. I
think Al will have about 4 inches between them when
separated.
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