X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from qmta14.emeryville.ca.mail.comcast.net ([76.96.27.212] verified) by logan.com (CommuniGate Pro SMTP 5.3.9) with ESMTP id 4486535 for flyrotary@lancaironline.net; Wed, 29 Sep 2010 18:04:47 -0400 Received-SPF: pass receiver=logan.com; client-ip=76.96.27.212; envelope-from=wschertz@comcast.net Received: from omta20.emeryville.ca.mail.comcast.net ([76.96.30.87]) by qmta14.emeryville.ca.mail.comcast.net with comcast id Cc1v1f0071smiN4AEm4CbP; Wed, 29 Sep 2010 22:04:13 +0000 Received: from WschertzPC ([71.57.77.95]) by omta20.emeryville.ca.mail.comcast.net with comcast id Cm471f00Y23NHuF8gm48Bg; Wed, 29 Sep 2010 22:04:12 +0000 Message-ID: <943189947C5C4ABC9B24F7DD0C9BDAC9@WschertzPC> From: "Bill Schertz" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Auto tune/oxygen sensor Date: Wed, 29 Sep 2010 17:04:05 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0088_01CB5FF8.52F57FE0" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8089.726 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8089.726 This is a multi-part message in MIME format. ------=_NextPart_000_0088_01CB5FF8.52F57FE0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Thanks to all, I picked up a Bosch sensor, and it indicates again. I = tried a little autotune, and need to compare the numbers. I think I = need to start all over again, because a number of the values are near = -120 -- I have the 520 injectors, and I may need to reduce injector flow = rate to get closer to where auto tune is happy. Bill Schertz KIS Cruiser #4045 N343BS Phase I testing From: Steven W. Boese=20 Sent: Wednesday, September 29, 2010 2:37 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Auto tune/oxygen sensor My take on the autotune function of the EM2/3 is that it uses the O2 = sensor output to make corrections to the table in the EC2/3 in the same = way as one would do it manually. It would only do this when the = autotune function is active and a completely corrected table would only = be obtained after performing the autotune in various flight regimes. = After the autotune function is deactivated, the EC2/3 continues to use = its corrected table with no further changes to it unless they are made = manually or by another autotune session. I don't think the EC2/3 uses = the O2 sensor output either directly or indirectly from the EM2/3 to = make instantaneous changes to mixture. Not having an EM2/3, this is = just my impression of the information I've seen. Surely there must be a = discription of the autotune function in the EM2/3 instructions? My older EC2's have a connection to an O2 sensor and the O2 sensor data = can be recovered by interrogating the EC2. This O2 sensor data does not = appear to be actually used by the EC2, however. Steve Boese -------------------------------------------------------------------------= ------- From: Rotary motors in aircraft [flyrotary@lancaironline.net] On Behalf = Of Ed Anderson [eanderson@carolina.rr.com] Sent: Wednesday, September 29, 2010 1:06 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Auto tune/oxygen sensor Al, is correct in that the EC does not directly interface with the O2 = sensor - however, because the autotune option does requires the EM2/3 = (at least I think I recall that being the case) to which the O2 sensor = is connected to, I suspect the following is a likely description of how = the autotune function works. My understanding that - the EM2 is a component of the Auto Tune system = of the EC.=20 I suspect that the EM2 has a circuit to read the O2 sensor voltage.=20 If the sensor is putting out around 0.450 volts (450 millivolts), then = the air/fuel ratio is close to stoichometric ratio of 14.7:1 air/fuel. = If the EC triggers the injectors and they produce a mixture that is = richer than 14.7:1 then the O2 voltage increases. This voltage swing is = probably detected by the EM2 and a mixture correction signal sent to the = EC to reduce the pulse width being sent to trigger the injectors thereby = reducing the air/fuel ratio and bringing it back to Stoichometric. = Should the O2 voltage drop below 450 millivolts (indicating leaner that = 14.7:1), that deviation is sense by the EM2 and a correction sent to the = EC to richen the mixture by increasing pulse width of signal sent to = injectors. So no EM2 - no autotune function, no Operational O2 sensor also equals = no AutoTune function. =20 But, just a SWAG on my part, Tracy may provide the correct description = if he gets back to the local Colorado Library {:>). Ed From: Al Gietzen=20 Sent: Wednesday, September 29, 2010 2:42 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Auto tune/oxygen sensor Bill; The EC is not a closed loop system =96 does not use the O2 sensor output = =96 unless something has changed recently. Al -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On = Behalf Of Bill Bradburry Sent: Wednesday, September 29, 2010 8:53 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Auto tune/oxygen sensor Bosch 11027 is the O2 sensor that Tracy recommends in the instructions. = I think the controller uses that input to maintain the mixture where you = set it. I don=92t think it is only used for setting the map table. = YMMV Bill B -------------------------------------------------------------------------= ------- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On = Behalf Of Al Gietzen Sent: Wednesday, September 29, 2010 12:07 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Auto tune/oxygen sensor I have the BOSCH sensor 11027 and it works fine. That=92s what I have also; and I think mine has something close to 150 = hrs and still going fine. I seldom burn avgas, so that helps. I think one needs the O2 sensor for auto tune. Yes, it does. As I understand it; with the knobs centered the EM tunes = to mid-range on the O2 sensor; roughly stoichometric. Al Rino ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Wednesday, September 29, 2010 11:05 AM Subject: [FlyRotary] Re: Auto tune/oxygen sensor Bill, if it=92s a one wire sensor, then just about any of the = "universal" 1 wire O2 sensors you find in your auto store will work.=20 If multiwire (I.e. has a heater element and a separate sensor ground = wire), then you need to get one with the same number of wires. If you = get the same make O2 sensor, then the wires should be the same color. Bosch has a wire chart which tells you which color wire is which - = this may help. I always get a Bosch unit - they might cost a few bucks = more, but they are generally good quality, available anywhere and you = can find the wire color code. Here's the wiring color code for the = "Universal" Bosch unit. Cable colour allocations for the Universal Oxygen Sensor are as = follows, sensor output signal wire =3D black, sensor heater element cables =3D White ( Note - heater is not polarity sensitive ) Sensor signal ground ( where used ) =3D Grey Important: The cable allocations must be assigned correctly. Otherwise the Sensor could be destroyed Don't let them sell you a wide band O2 sensor which a novice parts guy = might try to do because they all have 5 -6 wires and might get confused = with a Narrow band O2 sensor with a heater. Ed From: Bill Schertz=20 Sent: Wednesday, September 29, 2010 9:10 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Auto tune/oxygen sensor Was going to do some auto tune in the air yesterday, to get to some = regions of the performance map that can't be reached on the ground. Took off and the O2 sensor indication completely disappeared from the = EM-2 display. Did one circuit of the airport and landed. Discovered that the O2 sensor had failed (physically -- the top fell = off and separated from the body). This caused me to raise the following = questions. 1. I believe that the oxygen sensor readout is only that, not used by = the EC-2 for control purposes.=20 2. When in auto tune, is the EM-2 looking at the sensor for = indications of which way to adjust the mixture? If not, what is the = feedback mechanism? I went to the Auto parts store for a replacement, and ran into the = problem that there are 100's of different oxygen sensors, and they need = to know what car it came from. Anyone have the specs on what this sensor = is?=20 Bill Schertz KIS Cruiser #4045 N343BS Phase I testing ------=_NextPart_000_0088_01CB5FF8.52F57FE0 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
Thanks to all, I picked up a Bosch = sensor, and it=20 indicates again. I tried a little autotune, and need to compare the=20 numbers.  I think I need to start all over again, because a number = of the=20 values are near -120 -- I have the 520 injectors, and I may need to = reduce=20 injector flow rate to get closer to where auto tune is = happy.
 
Bill Schertz
KIS Cruiser=20 #4045
N343BS
Phase I testing

Sent: Wednesday, September 29, 2010 2:37 PM
Subject: [FlyRotary] Re: Auto tune/oxygen = sensor

My take on the autotune function of the EM2/3 is that it uses the = O2 sensor=20 output to make corrections to the table in the EC2/3 in the same way as = one=20 would do it manually.  It would only do this when the autotune = function is=20 active and a completely corrected table would only be obtained after = performing=20 the autotune in various flight regimes.  After the autotune = function is=20 deactivated, the EC2/3 continues to use its corrected table with no = further=20 changes to it unless they are made manually or by another autotune=20 session.  I don't think the EC2/3 uses the O2 sensor output either = directly=20 or indirectly from the EM2/3 to make instantaneous changes to = mixture.  Not=20 having an EM2/3, this is just my impression of the information I've = seen.  Surely there must be a discription of the autotune function = in the=20 EM2/3 instructions?
 
My older EC2's have a connection to an = O2 sensor=20 and the O2 sensor data can be recovered by interrogating the EC2.  = This O2=20 sensor data does not appear to be actually used by the EC2,=20 however.
 
Steve Boese
 
From: Rotary motors = in aircraft=20 [flyrotary@lancaironline.net] On Behalf Of Ed Anderson=20 [eanderson@carolina.rr.com]
Sent: Wednesday, September 29, = 2010 1:06=20 PM
To: Rotary motors in aircraft
Subject: = [FlyRotary] Re:=20 Auto tune/oxygen sensor

Al, is correct in that the EC does not directly = interface=20 with the O2 sensor - however, because the autotune option does requires = the=20 EM2/3 (at least I think I recall that being the case)  to =  which=20 the O2 sensor is connected to, I suspect the following is a likely = description=20 of how the autotune function works.
 
My understanding that - the EM2 is a component = of the Auto=20 Tune system of the EC. 
 
 I suspect that the EM2 has a circuit to = read the O2=20 sensor voltage. 
 
 If the sensor is putting out around 0.450 = volts (450=20 millivolts), then the air/fuel ratio is close to stoichometric ratio of = 14.7:1=20 air/fuel.  If the EC triggers the injectors and they produce a = mixture that=20 is richer than 14.7:1 then the O2 voltage increases.  This voltage = swing is=20 probably detected by the EM2 and a mixture correction signal sent to the = EC to=20 reduce the pulse width being sent to trigger the injectors thereby = reducing the=20 air/fuel ratio and bringing it back to Stoichometric.  Should the = O2=20 voltage drop below 450 millivolts (indicating leaner that 14.7:1), that=20 deviation is sense by the EM2 and a correction sent to the EC to richen = the=20 mixture by increasing pulse width of signal sent to = injectors.
 
So no EM2 - no autotune function, no Operational =  O2=20 sensor  also equals no AutoTune function. 
 
But, just a SWAG on my part, Tracy may provide = the correct=20 description if he gets back to the local Colorado Library = {:>).
 
Ed
 

From: Al Gietzen
Sent: Wednesday, September 29, 2010 2:42 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: Auto tune/oxygen = sensor

Bill;

 

The EC is = not a=20 closed loop system =96 does not use the O2 sensor output =96 unless = something has=20 changed recently.

 

Al

 

-----Original=20 Message-----
From: = Rotary=20 motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Bill = Bradburry
Sent: Wednesday, September 29, = 2010 8:53=20 AM
To: Rotary motors = in=20 aircraft
Subject: = [FlyRotary]=20 Re: Auto tune/oxygen sensor

 

Bosch=20 11027 is the O2 sensor that Tracy recommends in the instructions.  = I think=20 the controller uses that input to maintain the mixture where you set = it.  I=20 don=92t think it is only used for setting the map table. =20 YMMV

 

Bill=20 B

 

From: Rotary=20 motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al = Gietzen
Sent: Wednesday, September 29, = 2010 12:07=20 PM
To: Rotary motors = in=20 aircraft
Subject: = [FlyRotary]=20 Re: Auto tune/oxygen sensor

 

 

I have the BOSCH sensor = 11027 and it=20 works fine.

That=92s = what I have=20 also; and I think mine has something close to 150 hrs and still going = fine.=20  I seldom burn avgas, so that helps.

I think one needs the O2 = sensor for=20 auto tune.

Yes, it = does. =20 As I understand it; with the knobs centered the EM tunes to mid-range on = the O2=20 sensor; roughly stoichometric.

 

Al

 

 

Rino

----- Original Message = -----=20

From: Ed=20 Anderson

To: Rotary motors in = aircraft=20

Sent:=20 Wednesday, September 29, 2010 11:05 AM

Subject:=20 [FlyRotary] Re: Auto tune/oxygen sensor

 

Bill, if it=92s a one = wire sensor,=20 then just about any of the "universal" 1 wire O2 sensors you find in = your auto=20 store will work. 

 

 If multiwire (I.e. = has a=20 heater element and a separate sensor ground wire), then you need to = get one=20 with the same number of wires.  If you get the same make O2 = sensor, then=20 the wires should be the same color.

 

  Bosch has a wire = chart=20 which tells you which color wire is which  - this may help.  = I=20 always get a Bosch unit - they might cost a few bucks more, but they = are=20 generally good quality, available anywhere and you can find the wire = color=20 code.  Here's the wiring color code for the "Universal" Bosch=20 unit.

 

Cable=20 colour allocations for the Universal Oxygen Sensor are as=20 follows,

sensor=20 output signal wire =3D black, = sensor=20 heater element cables =3D

White (=20 Note - heater is not polarity sensitive ) Sensor signal=20 ground

( where=20 used ) =3D Grey

Important:=20 The cable allocations must be assigned correctly. = Otherwise

the Sensor=20 could be destroyed

 

Don't let them sell you = a wide=20 band O2 sensor which a novice parts guy might try to do because they = all have=20 5 -6 wires and might get confused with a Narrow band O2 sensor with a=20 heater.

 

Ed

 

From: Bill Schertz =

Sent:=20 Wednesday, September 29, 2010 9:10 AM

To: Rotary motors in = aircraft=20

Subject:=20 [FlyRotary] Auto tune/oxygen = sensor

 

Was going to do some = auto tune in=20 the air yesterday, to get to some regions of the performance map that = can't be=20 reached on the ground.

 

Took off and the O2 = sensor=20 indication completely disappeared from the EM-2 display. Did one = circuit of=20 the airport and landed.

 

Discovered that the O2 = sensor had=20 failed (physically -- the top fell off and separated from the body). = This=20 caused me to raise the following questions.

 

1. I believe that the = oxygen=20 sensor readout is only that, not used by the EC-2 for control = purposes.=20

2. When in auto tune, is = the EM-2=20 looking at the sensor for indications of which way to adjust the = mixture? If=20 not, what is the feedback mechanism?

 

I went to the Auto parts = store for=20 a replacement, and ran into the problem that there are 100's of = different=20 oxygen sensors, and they need to know what car it came from. Anyone = have the=20 specs on what this sensor is?

 

 

Bill=20 Schertz
KIS Cruiser=20 #4045
N343BS
Phase I=20 testing

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