X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from exchange.carey.wa.edu.au ([118.82.44.212] verified) by logan.com (CommuniGate Pro SMTP 5.3.9) with ESMTPS id 4487258 for flyrotary@lancaironline.net; Thu, 30 Sep 2010 09:22:40 -0400 Received-SPF: none receiver=logan.com; client-ip=118.82.44.212; envelope-from=stevei@carey.asn.au Received: from exchange.carey.local ([10.10.0.5]) by exchange.carey.local ([10.10.0.5]) with mapi; Thu, 30 Sep 2010 21:21:56 +0800 From: To: Date: Thu, 30 Sep 2010 21:22:06 +0800 Subject: Re: [FlyRotary] Re: Auto tune/oxygen sensor Thread-Topic: [FlyRotary] Re: Auto tune/oxygen sensor Thread-Index: ActgonQ1uQqwszRPQRSXGF7L3sbSeg== Message-ID: <81E36D8F-B1C7-469A-ADB1-3538E3CFAE5F@carey.asn.au> References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: multipart/alternative; boundary="_000_81E36D8FB1C7469AADB13538E3CFAE5Fcareyasnau_" MIME-Version: 1.0 --_000_81E36D8FB1C7469AADB13538E3CFAE5Fcareyasnau_ Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable See what you are saying Ed. Its not a true closed loop system, the feedback is used only to adjust a co= rrection factor in the map. Steve Izett On 30/09/2010, at 8:34 PM, Ed Anderson wrote: Hi Steve, I believe that is essentially the correction concept used for making the co= mparison between stoichometric and the O2 signal.. However, Steve Boese's comments about the Autotune function adjusting the f= uel map with the correction factor rather than my implied real-time adjust= ment of the Pulse to the injector, is the way it is actually implementati= on the EC/EM system. That way the adjustments are retained in the fuel map= . Ed From: stevei@carey.asn.au Sent: Thursday, September 30, 2010 12:42 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Auto tune/oxygen sensor Ed, I believe your description is right on. So autotune is a function of feedback to the EC2 from the EM2/3's O2 sensor= . Steve Izett On 30/09/2010, at 3:06 AM, Ed Anderson wrote: Al, is correct in that the EC does not directly interface with the O2 senso= r - 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 fu= nction works. My understanding that - the EM2 is a component of the Auto Tune system of t= he EC. I suspect that the EM2 has a circuit to read the O2 sensor voltage. 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 1= 4.7:1 then the O2 voltage increases. This voltage swing is probably detect= ed 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/fu= el ratio and bringing it back to Stoichometric. Should the O2 voltage drop= below 450 millivolts (indicating leaner that 14.7:1), that deviation is se= nse by the EM2 and a correction sent to the EC to richen the mixture by inc= reasing pulse width of signal sent to injectors. So no EM2 - no autotune function, no Operational O2 sensor also equals no= AutoTune function. But, just a SWAG on my part, Tracy may provide the correct description if h= e 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 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 Beh= alf 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 Beh= alf 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 ----- From: Ed Anderson To: Rotary motors in aircraft 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. 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 s= ame 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, bu= t 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 un= it. 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 migh= t 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 Sent: Wednesday, September 29, 2010 9:10 AM To: Rotary motors in aircraft 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 an= d 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 E= C-2 for control purposes. 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 wha= t car it came from. Anyone have the specs on what this sensor is? Bill Schertz KIS Cruiser #4045 N343BS Phase I testing ________________________________ The contents of this email are confidential and intended only for the named= recipients of this e-mail. If you have received this e-mail in error, you = are hereby notified that any use, reproduction, disclosure or distribution = or the information contained in this e-mail is prohibited. Please notify th= e sender immediately and then delete/destroy the e-mail and any printed cop= ies. All liability for viruses is excluded to the fullest extent of the law= . --_000_81E36D8FB1C7469AADB13538E3CFAE5Fcareyasnau_ Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable See what you are saying Ed= .
Its not a true closed loop system, the feedback is used only to adjus= t a correction factor in the map.

Steve Izett
<= div>
On 30/09/2010, at 8:34 PM, Ed Anderson wrote:

Hi Steve,
 
I believe that is essentially the correction = ;concept=20 used for making the comparison between stoichometric and the O2=20 signal..
 
However, Steve Boese's comments about the Autotun= e=20 function adjusting the fuel map with the correction factor  rather tha= n my=20 implied real-time adjustment of the Pulse to the injector,  is the way= it=20 is  actually implementation the EC/EM system.  That way the= =20 adjustments are retained in the fuel map.
 
Ed 

Sent: Thursday, September 30, 2010 12:42 AM
Subject: [FlyRotary] Re: Auto tune/oxygen sensor

Ed, I believe your description is right on.=20
So autotune is a function of feedback to the EC2 from the EM2/3's O2=20 sensor.

Steve Izett
On 30/09/2010, at 3:06 AM, Ed Anderson wrote:

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

Bill;

 

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

 

Al
<= p style=3D"MARGIN: 0in 0in 0pt; FONT-FAMILY: 'Times New Roman'; FONT-SIZE: = 12pt" class=3D"MsoNormal">= <= /font> 

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

&= nbsp;

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

 

Bill=20 B

 

<= font size=3D"3" face=3D"Times New Roman">
From: Rotary motors i= n aircraft=20 [mailto:flyrotary@lancaironline.net] On=20 Behalf Of Al= =20 Gietzen
Sent: Wednesday, September 29, 2010 12:= 07=20 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Auto tune/oxygen=20 sensor

 

 

I have the=20 BOSCH sensor 11027 and it works fine.
That=92s what I h= ave=20 also; and I think mine has something close to 150 hrs and still going fin= e.=20  I seldom burn avgas, so that helps.
I think=20 one needs the O2 sensor for auto tune.
Yes, it does.&nbs= p;=20 As I understand it; with the knobs centered the EM tunes to mid-range on = the=20 O2 sensor; roughly stoichometric.

 = ;

Al<= /div>

 

 

Rino
-----=20 Original Message -----
Sent: Wednesday, Septembe= r 29, 2010 11:05=20 AM
Subject:<= font size=3D"2" face=3D"Arial"> [FlyRotary] Re: = Auto tune/oxygen=20 sensor

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

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

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

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

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

the=20 Sensor could be destroyed

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

Ed

Sent: = Wednesday, September 29, 2010 9:10=20 AM
To:=  Ro= tary motors in=20 aircraft
Subject: [FlyRotary] Auto tune/oxygen=20 sensor

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

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

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

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

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

I went=20 to the Auto parts store for a replacement, and ran into the problem tha= t=20 there are 100's of different oxygen sensors, and they need to know what= car=20 it came from. Anyone have the specs on what this sensor=20 is?

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



The contents of this email a= re confidential=20 and intended only for the named recipients of this e-mail. If you have rece= ived=20 this e-mail in error, you are hereby notified that any use, reproduction,=20 disclosure or distribution or the information contained in this e-mail is=20 prohibited. Please notify the sender immediately and then delete/destroy th= e=20 e-mail and any printed copies. All liability for viruses is excluded to the= =20 fullest extent of the law.
= --_000_81E36D8FB1C7469AADB13538E3CFAE5Fcareyasnau_--