---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 08/21/06: 9 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:16 AM - Re: Bob's Dimmner and Electroluminescent strips (N941WR) 2. 11:03 AM - Re: MOV's (Eric M. Jones) 3. 01:15 PM - DPS FUELWATCH Instrument (Dave Saylor) 4. 07:37 PM - RPM drop Problem (dennisvh) 5. 08:19 PM - Re: RPM drop Problem (Kelly McMullen) 6. 08:23 PM - Re: RPM drop Problem (John D.Heath) 7. 08:31 PM - Re: RPM drop Problem (Richard Girard) 8. 09:40 PM - Pullable 80A Circuit Breaker (Speedy11@aol.com) 9. 10:25 PM - Super flag (John F. Herminghaus) ________________________________ Message 1 _____________________________________ Time: 05:16:15 AM PST US Subject: AeroElectric-List: Re: Bob's Dimmner and Electroluminescent strips From: "N941WR" --> AeroElectric-List message posted by: "N941WR" Ken, Thanks for the help. I hope to power it up for the first time today and see how it looks. If the strip is blinding I'll put a resistor in line with it. Bill -------- Bill RV-9 (Working on the finishing kit) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=56038#56038 ________________________________ Message 2 _____________________________________ Time: 11:03:39 AM PST US Subject: AeroElectric-List: Re: MOV's From: "Eric M. Jones" --> AeroElectric-List message posted by: "Eric M. Jones" Coil Suppression: MOVs are considered to be better than diodes, although they have higher impedance. But MOVs typically have a limited lifetime. Diodes are not the best method today. Not even the second-, third-, or fourth- best method. But in the 1960's they were the way to go. Mechanical relays and contactors depend upon magnetism generated by an electric current running through a wire coil. When the current stops, the magnetic field collapses. But the relay does not know the difference between a wire coil moving in a magnetic field (as in a generator) or a magnetic field moving in a wire coil (as in a collapsing magnetic field). Thus a large voltage1000V to 1500V typicallyis induced in the coil. This current goes the same direction the original current didso it slows the contact openingallowing arcing, chatter, bouncing, contact welding and even re-closure! Perihelion Design sells 18V 600W Bi-Directional Zener Transient Voltage Suppressors (for 14.5V systems) that provide the most modern Third Millennium technical solution to relay coil suppression. We sell these as a set of twelve with the typical hardware needed to retrofit a small airplane. Every manufacturer of bi-directional Zener transient voltage suppressors seems to have a trademarked name for these: Transils, Surmetics, Transorbs, TranZorbs, TransGuards, Mosorbs; the list is endless. We call them SnapJacks. They also are offered in a range of voltages, packages, and wattages. Perihelion Design offers the 18 Volt 600 Watt axial lead version of these guys, commonly known to close friends as P6KE18CA, and includes some of the connectors and shrink tubing you may need to install them. Basic Plan: SnapJacks are used to replace coil suppression diodes wherever they are now installed. For coils, contactors and relays that are internally equipped with a suppression diode, the best solution may be to buy the equivalent non-diode part. If possible, install the SnapJacks with the shortest leads possible consistent with strain relief and mechanical mounting of the part. SnapJacks have NO POLARITY, regardless of any marking on the parts. Although the 600 W parts will work fine with the biggest relay, contactor, or motor that your aircraft could lift, you may wish to parallel two SnapJacks on the big loads for redundancy. In some cases diodes associated with contactors are there for switching logic purposes, not suppression. These should be left alone. ref: http://relays.tycoelectronics.com/kilovac/appnotes/transients.asp See: http://www.periheliondesign.com/suppressors/SnapJack.pdf -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones@charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=56118#56118 ________________________________ Message 3 _____________________________________ Time: 01:15:41 PM PST US From: "Dave Saylor" Subject: AeroElectric-List: DPS FUELWATCH Instrument --> AeroElectric-List message posted by: "Dave Saylor" Listers, Does anyone have a fuel monitor called a "DPS FUELWATCH"? It fits a 2 1/4" hole and has a DB9 connector on the back. I've never seen one before. We are repairing a plane damaged by fire that uses an instrument like this, and I need to know how to rewire it and what type of transducer it uses. Anybody have any information? Many thanks, Dave Saylor AirCrafters LLC 140 Aviation Way Watsonville, CA 831-722-9141 www.AirCraftersLLC.com ________________________________ Message 4 _____________________________________ Time: 07:37:19 PM PST US Subject: AeroElectric-List: RPM drop Problem From: "dennisvh" --> AeroElectric-List message posted by: "dennisvh" I have a 1946 Ercoupe with a 85 HP (started out as a 75HP) Continental engine with a 200 RPM drop on the right mag at run-up. Mechanics have 100% eliminated as the problem both mags, all plugs, P-leads, and switch system. Also, the engine ran perfectly for the last 25 hours after a new wiring harness was installed. The harness was checked out and all wires were fine. We do not know what to check next. I would appreciate any advice anyone can give us. Thanks. Dennis Hatfield [Question] Read this topic online here: http://forums.matronics.com/viewtopic.php?p=56221#56221 ________________________________ Message 5 _____________________________________ Time: 08:19:25 PM PST US From: Kelly McMullen Subject: Re: AeroElectric-List: RPM drop Problem --> AeroElectric-List message posted by: Kelly McMullen Well, you don't mention the timing being checked. dennisvh wrote: > --> AeroElectric-List message posted by: "dennisvh" > > I have a 1946 Ercoupe with a 85 HP (started out as a 75HP) Continental engine with a 200 RPM drop on the right mag at run-up. Mechanics have 100% eliminated as the problem both mags, all plugs, P-leads, and switch system. Also, the engine ran perfectly for the last 25 hours after a new wiring harness was installed. The harness was checked out and all wires were fine. We do not know what to check next. I would appreciate any advice anyone can give us. Thanks. Dennis Hatfield [Question] > ________________________________ Message 6 _____________________________________ Time: 08:23:03 PM PST US From: "John D.Heath" Subject: Re: AeroElectric-List: RPM drop Problem --> AeroElectric-List message posted by: "John D.Heath" Dennis, The only thing left is timing. If the Mags have not been moved, the timing might be off because the impulse coupling does not return to the stop or because the point gaps are wrong. Point gaps change because of metal transfer at the contacts indicating a condenser problem or the fiber block that follows the point cam is worn away by a rusty cam. Good Luck John D. DO NOT ARCHIVE We do not know what to check next. I would appreciate any advice anyone can give us. Thanks. Dennis Hatfield ________________________________ Message 7 _____________________________________ Time: 08:31:19 PM PST US From: "Richard Girard" Subject: Re: AeroElectric-List: RPM drop Problem You say that mechanics have 100% eliminated. What did they do to eliminate those items? It'll save a lot of guessing games if you tell us that. On 8/21/06, Kelly McMullen wrote: > > --> AeroElectric-List message posted by: Kelly McMullen < > kellym@aviating.com> > > Well, you don't mention the timing being checked. > > dennisvh wrote: > > --> AeroElectric-List message posted by: "dennisvh" < > dennisvh@adelphia.net> > > > > I have a 1946 Ercoupe with a 85 HP (started out as a 75HP) Continental > engine with a 200 RPM drop on the right mag at run-up. Mechanics have 100% > eliminated as the problem both mags, all plugs, P-leads, and switch > system. Also, the engine ran perfectly for the last 25 hours after a new > wiring harness was installed. The harness was checked out and all wires > were fine. We do not know what to check next. I would appreciate any > advice anyone can give us. Thanks. Dennis Hatfield [Question] > > > > -- Rick Girard "Ya'll drop on in" takes on a whole new meaning when you live at the airport. ________________________________ Message 8 _____________________________________ Time: 09:40:34 PM PST US From: Speedy11@aol.com Subject: AeroElectric-List: Pullable 80A Circuit Breaker Does anybody know a source for a pullable 80A CB to use for the alternator? I've checked several sources and have found 80A CBs that cannot be pulled - they can only be reset, but none that are pullable. I bought one at Sun n Fun only to discover later that it is 28v. Stan Sutterfield ________________________________ Message 9 _____________________________________ Time: 10:25:40 PM PST US From: "John F. Herminghaus" Subject: AeroElectric-List: Super flag --> AeroElectric-List message posted by: "John F. Herminghaus" What is a super flag? Is there any source where it is described in detail? John Herminghaus