Return-Path: <13brv3@bellsouth.net> Received: from imf19aec.mail.bellsouth.net ([205.152.59.67] verified) by logan.com (CommuniGate Pro SMTP 4.2) with ESMTP id 377990 for flyrotary@lancaironline.net; Wed, 25 Aug 2004 14:46:32 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.67; envelope-from=13brv3@bellsouth.net Received: from rd ([65.6.194.9]) by imf19aec.mail.bellsouth.net (InterMail vM.5.01.06.08 201-253-122-130-108-20031117) with ESMTP id <20040825184557.LVCN1789.imf19aec.mail.bellsouth.net@rd> for ; Wed, 25 Aug 2004 14:45:57 -0400 From: "Russell Duffy" <13brv3@bellsouth.net> To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] EM2 users Date: Wed, 25 Aug 2004 13:46:06 -0500 Message-ID: <023701c48ad3$c7a26de0$6101a8c0@rd> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0238_01C48AA9.DECC65E0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 This is a multi-part message in MIME format. ------=_NextPart_000_0238_01C48AA9.DECC65E0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Local barometric pressure is 30.02, so I expect it to give me this = number as MP. With EC2 turned off it reads MP as 29.2 - I assume it is reading = this with the sensor in the EM2. With EC2 on (data feed from EC2) it reads = 32.3. Neither of the readings is correct. Should I be concerned? First, I'd like to point out that I don't have the best answers for your questions, but I'll say what I can. =20 =20 Tracy explained that there's only one calibration area for the MAP = reading, so you can only have one sensor correct. Since you have an EC-2, that's = the one you'll use. As for the reading you're getting with the EC-2 turned = on, but engine not running, ignore it. Mine read 20.4, and I'm guessing = it's the last reading that it sampled when the engine was running. When I = hooked a gauge up to my engine, and compared the reading with the EM-2 while = the engine was running, all was well. Unfortunately, I don't see a way to = check the MAP reading with the engine off. =20 Battery voltage reads about .75 lower than my voltmeter reads at the breaker. I haven't checked the voltage cal on mine, but imagine that if anything = is correct, this would be. When you say at the breaker, do you mean the breaker that feeds the EM-2? If you have one of electric Bob's = essential buss setups, with a diode between the two busses, that will drop your voltage close to what you're seeing. The RWS air temp sensors (I have 3) all read 6-8 degrees lower than = actual air temp (75F at the time). I expect these should be accurate. If you're referring to the 3 wire sensors, Tracy said they were always = very accurate by definition, assuming they're wired correctly. However, my = OAT temp was reading about 15 degrees low. I ended up zeroing out the = sensor offset, and got the OAT reading within about 4 degrees of what I was = reading with the Radio Shack thermometer. That's where I left it for now. =20 The J-type TCs read right on air temp. The K-type TCs are about 5-7 low = at ambient temps, that doesn't really matter. Oil and coolant temps were somewhat off, but I adjusted calibration = factors to get them about right. But didn't quite know whether to change 'Low = end offset' or the 'Sensor offset'. I assume for the VDO sensors the scale factors are correct.=20 My temps were pretty good on the latest EM-2 software that I just = installed. Pressures were the problem, and I'm not sure why they were so = significantly off from the previous version. The sensors I'm using are still the same ones recommended, but I was able to calibrate them reasonably well. For example, my fuel pressure was 42 psi before, but came up 59 on the new = sw. Oil on the new sw was ringing the bell at about 88 psi, when in = actuality, it's about 75 psi. =20 I wish I could give you a clear definition of sensor offset vs. low end offset, but I'm not sure I can. All the settings seem to interact, = which can be a bit frustrating to calibrate. One of the most powerful = features of the EM-2 is it's ability to adapt to any number of different sensors, = but this comes at a price of being responsible for it's calibration. The = best we can hope for is to have certain known sensors precalibrated, and I'm = sure Tracy will perfect this at some point. As I said, my temps are pretty = OK, but not the pressures. =20 The more general question on temp calibration is, short of taking out = the sensor and putting it in boiling water, what's a good (read easy) way to = get another reference point at something like operating temp? I got a spare of every type of sensor that I'm using, which gives me the ability to calibrate everything, without pulling any of the actual = sensors out of the engine. The caveat here is that all sensors are somewhat different, but I'm betting any two of the same brand and type of sensor = are close enough for our purposes. =20 The best test I can think of for water temp is boiling water, though = it's hard to keep it at 212 degrees for any length of time. I have a = microwave in the hanger, and can heat water that way. I also have a calibrated thermocouple that I use to measure the water at the same time I put the sensor in it for calibration. That way, you can calibrate to the temp = of the thermocouple. =20 For pressure, I made an adapter that uses a T to connect a pressure = sensor, gauge, and my air compressor hose. That allows you to use the = compressor to set whatever pressure you want to read, and you can confirm it with the gauge. This has worked fairly well. =20 =20 Anybody using 'Aux Liquid temps' 2&3? Mine aren't working right. I'm using two of the aux liquid temps for oil pan, and water into the engine, but I can't recall the exact designations of the channels. In fairness to my failing memory, they do tend to change names from one = page to the next, much like the buttons do :-) I know these were working fine = in the previous software version, but just made a note to confirm they're working now. =20 =20 John probably knows how this all works. After all, he's had lots of = time on his hands recently to play with it :-) =20 =20 Cheers, Rusty (Where's the turbo now John) ------=_NextPart_000_0238_01C48AA9.DECC65E0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message

Local barometric pressure is 30.02, so I expect it to = give me=20 this number as MP.  With EC2 turned off it reads MP as 29.2 – = I assume it=20 is reading this with the sensor in the EM2.  With EC2 on (data feed = from=20 EC2) it reads 32.3.  Neither of the readings is correct.  = Should I be=20 concerned?

First, = I'd like to point=20 out that I don't have the best answers for your questions, but I'll say = what I=20 can. 
 
Tracy = explained that=20 there's only one calibration area for the MAP reading, so you can only = have one=20 sensor correct.  Since you have an EC-2, that's the one you'll = use. =20 As for the reading you're getting with the EC-2 turned on, but engine = not=20 running, ignore it.  Mine read 20.4, and I'm guessing it's the last = reading=20 that it sampled when the engine was running.  When I hooked a gauge = up to=20 my engine, and compared the reading with the EM-2 while the engine was = running,=20 all was well.  Unfortunately, I don't see a way to check the = MAP=20 reading with the engine off. 

Battery voltage reads about .75 lower than my voltmeter reads at the=20 breaker.

I haven't checked the = voltage cal on=20 mine, but imagine that if anything is correct, this would be.  When = you say=20 at the breaker, do you mean the breaker that feeds the EM-2?  If = you have=20 one of electric Bob's essential buss setups, with a diode between the = two=20 busses, that will drop your voltage close to what you're = seeing.

The RWS air temp sensors (I have 3) all read 6-8 degrees lower than = actual=20 air temp (75F at the time).  I expect these should be accurate.

If you're referring to = the 3 wire=20 sensors, Tracy said they were always very accurate by definition, = assuming=20 they're wired correctly.  However, my OAT temp was reading about 15 = degrees=20 low.  I ended up zeroing out the sensor offset, and got = the OAT=20 reading within about 4 degrees of what I was reading with the Radio = Shack=20 thermometer.  That's where I left it for now. =   

 The J-type TCs read right on air temp. The K-type TCs are about = 5-7 low=20 at ambient temps, that doesn’t really matter.
Oil and coolant = temps were=20 somewhat off, but I adjusted calibration factors to get them about = right. =20 But didn’t quite know whether to change ‘Low end = offset’ or the ‘Sensor=20 offset’.  I assume for the VDO sensors the scale factors are=20 correct. 

My temps were pretty good = on=20 the latest EM-2 software that I just installed.  Pressures = were the=20 problem, and I'm not sure why they were so significantly off from the = previous=20 version.  The sensors I'm using are still the same ones = recommended, but I=20 was able to calibrate them reasonably well.  For example, my fuel = pressure=20 was 42 psi before, but came up 59 on the new sw.  Oil on the new sw = was=20 ringing the bell at about 88 psi, when in actuality, it's about 75 = psi. =20

I wish I could give you a = clear=20 definition of sensor offset vs. low end offset, but I'm not = sure I=20 can.  All the settings seem to interact, which can be = a bit=20 frustrating to calibrate.  One of the most powerful features=20 of the EM-2 is it's ability to adapt to any number of different = sensors,=20 but this comes at a price of being responsible for it's = calibration. =20 The best we can hope for is to have certain known sensors = precalibrated,=20 and I'm sure Tracy will perfect this at some point.   As I = said, my=20 temps are pretty OK, but not the pressures.   

The more general question on temp calibration is, short of taking out = the=20 sensor and putting it in boiling water, what’s a good (read easy) = way to get=20 another reference point at something like operating temp?

I got a spare of every = type of sensor=20 that I'm using, which gives me the ability to calibrate everything, = without=20 pulling any of the actual sensors out of the engine.  The caveat = here is=20 that all sensors are somewhat different, but I'm betting any two of the = same=20 brand and type of sensor are close enough for our purposes.  =

The best test I can think = of for water=20 temp is boiling water, though it's hard to keep it at 212 degrees for = any length=20 of time.  I have a microwave in the hanger, and can heat water that = way.  I also have a calibrated thermocouple that I use to measure = the water=20 at the same time I put the sensor in it for calibration.  That way, = you can=20 calibrate to the temp of the thermocouple. 

For pressure, I made an = adapter that=20 uses a T to connect a pressure sensor, gauge, and my air compressor = hose. =20 That allows you to use the compressor to set whatever pressure you want = to read,=20 and you can confirm it with the gauge.  This has worked fairly = well. =20
 
Anybody using ‘Aux Liquid temps’ 2&3?   = Mine aren’t working=20 right.
I'm using two of the = aux liquid temps=20 for oil pan, and water into the engine, but I can't recall the exact=20 designations of the channels.  In fairness to my failing memory, = they do=20 tend to change names from one page to the next, much like the buttons=20 do :-)   I know these were working fine in the previous = software=20 version, but just made a note to confirm they're working now. =20
 
John probably knows how = this all=20 works.  After all, he's had lots of time on his hands recently to = play with=20 it :-) 
 
Cheers,
Rusty (Where's the = turbo now=20 John)
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