X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imf16aec.mail.bellsouth.net ([205.152.59.64] verified) by logan.com (CommuniGate Pro SMTP 4.3.2) with ESMTP id 961592 for flyrotary@lancaironline.net; Tue, 24 May 2005 04:17:24 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.64; envelope-from=sladerj@bellsouth.net Received: from ibm58aec.bellsouth.net ([65.2.89.207]) by imf16aec.mail.bellsouth.net (InterMail vM.5.01.06.11 201-253-122-130-111-20040605) with ESMTP id <20050524081640.RQUZ7916.imf16aec.mail.bellsouth.net@ibm58aec.bellsouth.net> for ; Tue, 24 May 2005 04:16:40 -0400 Received: from JSLADE ([65.2.89.207]) by ibm58aec.bellsouth.net (InterMail vG.1.02.00.01 201-2136-104-101-20040929) with ESMTP id <20050524081639.WSML25991.ibm58aec.bellsouth.net@JSLADE> for ; Tue, 24 May 2005 04:16:39 -0400 From: "John Slade" To: "Rotary motors in aircraft" Subject: RE: [FlyRotary] Re: EC2 problems Date: Tue, 24 May 2005 04:16:38 -0400 Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0260_01C56017.61B12200" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 In-Reply-To: Importance: Normal This is a multi-part message in MIME format. ------=_NextPart_000_0260_01C56017.61B12200 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Hi Tracy, I hope you're refreshed and in a really good mood after your vacation. Thanks very much for the report. I'm responding in detail here in case others can learn from my misfortune.... I have good news, and I have bad news. First the good news. Howard (Cozy builder from Clearwater who is something of an electronics wiz and has visited you recently) flew down here today and worked with me for 9 hours on the plane. I have been suspicious of my coil disable circuit. I discussed this plan with you by phone many moons ago when I was installing it. Perhaps you didn't follow what I was planning to do. I connected the center pin on my standard Left, right, both ignition switch to the EC2 ground, then connected the coil disable pins on the EC2 to the left and right mag terminals on the ignition switch. This way "off" would disable both coils, Left would disable leading, etc. The setup has been like this from day 1. Today, while waiting for Howard, I put a volt meter between the center pin of the ignition switch and ground, and cranked the engine. Would you believe 1.5 volts? Second time I tried it the reading was just a few millivolts. Next time it was 1.5 volts again, then I couldn't duplicate it. 1.5 volts down the coil disable ground wire would be a bad thing - right? When Howard arrived the first thing he produced, without any prompting, was a schematic for the standard ignition switch produced by Bob Nuckolls which carries, in very small print, a warning not to connect the center ground pin to any other ground in the aircraft. Oops. I have the same schematic in my folder of circuit diagrams, with the same warning. I guess I missed it. We tested with his computer logging equipment and couldn't repeat the problem. In any case, I have separate switching for the coils and have removed this wiring since the function is redundant anyway. We went on to identify significant "ground bounce" in the coil circuit which led to remaking the coil harness and replacing the existing crimped single ground with a soldered and crimped ground wire from each coil. Howard also pointed out that the CAS cable and some sensor wires, including the intake temp wires, go very close to the coil leads, are bundled with the heavy starter wire, and should be moved. The engine ground was a bit weak and the ground strap was cleaned and reconnected. The coil grounding was much improved after all this. All in all we identified a number of ground leaks, loops and bounces, any and all of which could have been causing problems. Additionally, Howard left me with a very simple, cheap and extremely useful testing setup made with two voltmeters and a D cell battery which allows me to test a circuit under load and identify any weak connections, bad crimps, cold solder joints etc. With this little gizmo I am newly empowered, and have a lot more testing to do. And now the bad news... I'll have plenty of time for testing. After 8 hours work in a very hot hangar it came time to connect Howard's circa 2001 EC2 to my harness and see what we had. As I was working in the back of the plane to hook up the EC2 to the harness Howard walked around, stopped me, and insisted that I hook up the ground first. So, I hooked the ground wires to the EC2 ground pin, but it was a little dark in the back, sweat was dripping in my eyes and I missed one. Guess which one. Yep - the main ground lead for the EC2. You probably don't need to read the rest. We powered the system up and cranked the engine with the data logging equipment hooked up to the primary injector 12v lead. The was no data. This was when I noticed that the EM2 now had a blank screen. To cut a really long story to just a long one I'll cut out the Indian war dance, and the fist through the hangar wall bit and cut to the chase - I managed to fry $1800 + worth of electronics in 5 seconds by failing to spot one important little wire in a bundle. This, perhaps, will explain why I can't sleep and am typing this at 4am. :( So, the EM2 board (please shout if you need the screen too) will be on its way back in the morning. I'm not even addressing it - it knows its own way. Also, eventually Howard's EC2 is going to need a little extra work when it comes back in for its upgrade. Finally, just to end on a good note - a suggestion I made to Howard seems to make sense for novices like me who are installing equipment that doesn't react well to volts in the wrong places. A simple 37 pin male female adapter with a few diodes and leds that glow red when there's a voltage on an inappropriate pin. Green LEDs could be used to indicate cold start, program store and even mixture and program voltage by dimming. With a little thought and $5 in materials I think even I could probably hack one of these together. You could probably do it in 20 minutes. You could ship one of these little "EC2 Savers" with every EC2 for use and return by the builder. A similar 15 pin EM2 saver could also be built. This might save you a LOT of warranty work. Regards, John (not accepting calls today) ------=_NextPart_000_0260_01C56017.61B12200 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi=20 Tracy,
I hope you're refreshed and in = a=20 really good mood after your = vacation.
Thanks = very much for=20 the report. I'm responding in detail here in case others can learn = from my=20 misfortune.... 
 
I have good=20 news, and I have bad news.
 
First = the good news.=20
Howard (Cozy builder from Clearwater who is = something of an=20 electronics wiz and has visited you recently) flew down here today and = worked=20 with me for 9 hours on the plane.
 
I have been suspicious of my coil disable circuit. = I discussed=20 this plan with you by phone many moons ago when I was installing it. = Perhaps you=20 didn't follow what I was planning to do. I connected the center pin = on my=20 standard Left, right, both ignition switch to the EC2 ground, then = connected the=20 coil disable pins on the EC2 to the left and right mag terminals on the = ignition=20 switch. This way "off" would disable both coils, Left would disable = leading,=20 etc. The setup has been like this from day 1. Today, while waiting for = Howard, I=20 put a volt meter between the center pin of the ignition switch and = ground, and=20 cranked the engine. Would you believe 1.5 volts? Second time I tried it = the=20 reading was just a few millivolts. Next time it was 1.5 volts again, = then I=20 couldn't duplicate it. 1.5 volts down the coil disable ground wire would = be a=20 bad thing - right?
 
When = Howard arrived=20 the first thing he produced, without any prompting, was a schematic for = the=20 standard ignition switch produced by Bob Nuckolls which carries, in very = small=20 print, a warning not to connect the center ground pin to any other = ground in the=20 aircraft. Oops. I have the same schematic in my folder of circuit = diagrams, with=20 the same warning. I guess I missed it. We tested=20 with his computer logging equipment and couldn't repeat the problem. = In=20 any case, I have separate switching for the coils and have removed this = wiring=20 since the function is redundant anyway.
 
We = went on=20 to identify significant "ground bounce" in the coil circuit = which led=20 to remaking the coil harness and replacing the existing crimped single = ground=20 with a soldered and crimped ground wire from each coil. Howard also = pointed out=20 that the CAS cable and some sensor wires, including the intake temp = wires, go=20 very close to the coil leads, are bundled with the heavy starter wire, = and=20 should be moved. The engine ground was a bit weak and the ground = strap was=20 cleaned and reconnected. The coil grounding was much improved after all=20 this.
 
All in = all we=20 identified a number of ground leaks, loops and bounces, any and all = of=20 which could have been causing problems. Additionally, Howard left me = with a very=20 simple, cheap and extremely useful testing setup made with two = voltmeters and a=20 D cell battery which allows me to test a circuit under load and = identify=20 any weak connections, bad crimps, cold solder joints etc. With this = little gizmo=20 I am newly empowered, and have a lot more testing to do. =
 
And now the=20 bad news...
I'll = have plenty of=20 time for testing. After 8 hours work in a very hot hangar it came time = to=20 connect Howard's circa 2001 EC2 to my harness and see what we had. As I = was=20 working in the back of the plane to hook up the EC2 to the harness = Howard walked=20 around, stopped me, and insisted that I hook up the ground first. = So, I=20 hooked the ground wires to the EC2 ground pin, but it was a little = dark in=20 the back, sweat was dripping in my eyes and I missed one. Guess which = one. Yep -=20 the main ground lead for the EC2. You probably don't need to read the=20 rest.
 
We = powered the=20 system up and cranked the engine with the data logging equipment hooked = up to=20 the primary injector 12v lead. The was no data. This was when I noticed = that the=20 EM2 now had a blank screen. To cut a really long story to just a long = one I'll=20 cut out the Indian war dance, and the fist through the hangar wall bit = and cut=20 to the chase - I managed to fry $1800 + worth of electronics in 5 = seconds by=20 failing to spot one important little wire in a bundle. This, perhaps, = will=20 explain why I can't sleep and am typing this at 4am. = :(
 
So, = the EM2 board=20 (please shout if you need the screen too) will be on its way back in the = morning. I'm not even addressing it - it knows its own way.  Also,=20 eventually Howard's EC2 is going to need a little extra work = when it=20 comes back in for its upgrade.
 
Finally, just to end=20 on a good note - a suggestion I made to Howard seems to make sense for = novices=20 like me who are installing equipment that doesn't react well to volts in = the=20 wrong places. A simple 37 pin male female adapter with a few diodes and = leds=20 that glow red when there's a voltage on an inappropriate pin. Green LEDs = could=20 be used to indicate cold start, program store and even mixture and = program=20 voltage by dimming. With a little thought and $5 in materials I think = even I=20 could probably hack one of these together. You could probably do it in = 20=20 minutes. You could ship one of these little "EC2 Savers" with every EC2 = for use=20 and return by the builder. A similar 15 pin EM2 saver could also be = built.=20 This might save you a LOT of warranty work.
 
Regards,
John = (not accepting=20 calls today)
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