flyrotary@lancaironline.net Mailing List Archive

Without knowing details of Tracy's design, hard to say what the real consequences of relocating the switches is. Tracy did explicitly state in the manual I got with my EC2 that relocating the switches is an acceptible option. In any case relocating the switches should not result in any sort of a "ground loop". Nothing much to report today. On my first start today the engine quit when I switched to the B controller. I had to do a A > B copy to get the engine to run on B. Test ran for another 1.5 hours or so with multiple starts, toggling back and forth between A and B, but could not force it to fail again. Which is kinda disappointing. But thats the nature of an intermittant, isnt it? About the only thing I can report is that the engine runs richer throughout the RPM range on B than it does on A. A is setup so that its at stoich with the mixture knob at 12:00. On B the mixture knob needs to be at 9:00 for the same indication on the mixture gauge. Mike Wills RV-4 N144MW ----- Original Message ----- From: "Jeff Whaley" <jwhaley@datacast.com> To: "Rotary motors in aircraft" <flyrotary@lancaironline.net> Sent: Thursday, July 02, 2009 10:07 AM Subject: [FlyRotary] Re: frustrating couple of days I believe the ground for the controller unit is made through the DB15 wire harness to the EC2; by moving the A/B switch you will have lengthened this ground loop ... maybe try a wire from Controller PCB common to ground of remote A/B switch. Is it possible for you to put the A/B switch back to original position? Jeff -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ed Anderson Sent: Thursday, July 02, 2009 12:53 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: frustrating couple of days Mike, per discussion about possible de-bouncing problem. Might try sticking a 0.01 ufd capacitor from your Controller Switch to Ground - just to eliminate debouncing as the potential problem. Ed Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://www.dmack.net/mazda/index.html http://www.flyrotary.com/ http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.rotaryaviation.com/Rotorhead%20Truth.htm -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mike Wills Sent: Thursday, July 02, 2009 12:09 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: frustrating couple of days Minor correction. Its not that I'm only seeing a problem with the B controller. Its that it appears that the problem occurs when I switch to B, but in the 2 cases where the staging point was corrupted, the corrupt data was on the A controller. I've been all through the power and ground system. Multiple times. When I first noted the problem and emailed Tracy about it he suspected ground noise. After describing my electrical system to him he made two suggestions: 1) I implemented a single point ground even though I have a metal airframe. I wanted to avoid ground currents getting into the radio and intercom. Due to CG issues my batteries ended up in the baggage compartment so the ground connection from the batteries to the single point ground ended up being about 8' of #0 cable. Tracy recommended eliminating this cable and tying the battery ground terminals to chassis ground as close as possible to the batteries. I've done this. 2) My ignition coils were also connected to the single point ground through about 3' of #14 wire. Tracy indicated that the coils are the greatest potential noise makers on the airplane and recommended grounding this to the airframe or engine block as close as possible to the coils. I've done this. I've reviewed all of my wiring to make sure that things that should be shielded are and to be sure that noisy wires are seperated from sensitive ones. There were no obvious problems found in my original install in this regard, but I did move a couple of wires to gain even more seperation. So as I said, I believe the power and ground system in the airplane are sound. I doubt that remoting the A/B switch, or something wrong with the switch itself, is what is causing this, but I do believe that something is going on in the act of switching from A to B that is causing the problem. I'll try to force it in my testing today. Mike Wills RV-4 N144MW ----- Original Message ----- From: "thomas walter" <roundrocktom@yahoo.com> To: "Rotary motors in aircraft" <flyrotary@lancaironline.net> Sent: Thursday, July 02, 2009 7:26 AM Subject: [FlyRotary] Re: frustrating couple of days Ed, Odd electrical trivia. Older eeproms were rated at 3.3V, so below 2.7V they ignored any read or write information. We had a uC that would start "jabbering" on the data and clock lines when power was caming up. Since reset occurred once power was good, it was never an issue. Problem is the eeprom manufactures started shipping parts that were functional from 1.8V to 3.3V. So once power was at 1.7V, it accepted writes, corrupting the eeprom. Just to drive the engineers crazy only some lots and some devices 'jibbered' away. Yes, amazing I still have any hair left. :) That is pretty rare, but has happened. Yes, Mike -- Interesting you're only seeing an issue with the "B" controller. Still triple check the power, grounds, and rest of the connections. Since the fuel map is stored in non-volute memory, it's hard to figure out how it is being re-written or destroyed. Normally (as you know) access to EEPROM on a chip is a rather non-trivial process. Since the A and B controller are two different chips, I suppose there could be a problem with the B chip - but, while that does happen, it's pretty rare. Have not had one myself (yet). -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html __________ Information from ESET NOD32 Antivirus, version of virus signature database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com __________ Information from ESET NOD32 Antivirus, version of virus signature database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html