---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 06/07/07: 24 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:04 AM - Re: Runaway trim (Fiveonepw@aol.com) 2. 07:01 AM - Re: Runaway trim (Valovich, Paul) 3. 08:02 AM - Runaway trim (Fergus Kyle) 4. 08:35 AM - Re: Isolated DC-DC Electronics design pointers (Ron Quillin) 5. 08:44 AM - Re: Runaway trim (Ron Quillin) 6. 09:23 AM - Re: First Start of my rotary (Hinde, Frank George (Corvallis)) 7. 09:23 AM - Re: Runaway trim (john@ballofshame.com) 8. 11:00 AM - Re: Runaway trim (Buckaroo Banzai) 9. 11:07 AM - Re: First Start of my rotary (Ernest Christley) 10. 11:38 AM - Re: Runaway trim (Robert L. Nuckolls, III) 11. 01:47 PM - Re: Runaway trim (Kevin Horton) 12. 01:47 PM - Re: Runaway trim (Kevin Horton) 13. 01:52 PM - Re: Runaway trim (Doug Windhorn) 14. 02:36 PM - Re: Runaway trim (Kevin Horton) 15. 03:52 PM - Re: Isolated DC-DC Electronics design pointers (Ralph Hoover) 16. 05:17 PM - Re: Runaway trim (Glen Matejcek) 17. 06:24 PM - JJN 80 Amp "Boltable" Fuse Source (Michel Creek) 18. 06:43 PM - Re: JJN 80 Amp "Boltable" Fuse Source (Michael T. Ice) 19. 07:02 PM - Re: JJN 80 Amp "Boltable" Fuse Source (Michel Creek) 20. 07:15 PM - Re: Runaway trim (Robert L. Nuckolls, III) 21. 08:04 PM - Re: JJN 80 Amp "Boltable" Fuse Source (Robert L. Nuckolls, III) 22. 08:52 PM - Re: JJN 80 Amp "Boltable" Fuse Source (Joemotis@aol.com) 23. 08:58 PM - Re: JJN 80 Amp "Boltable" Fuse Source (Joemotis@aol.com) 24. 09:11 PM - Annunciator HELP! (Fiveonepw@aol.com) ________________________________ Message 1 _____________________________________ Time: 12:04:37 AM PST US From: Fiveonepw@aol.com Subject: Re: AeroElectric-List: Runaway trim In a message dated 6/6/2007 11:03:59 PM Central Daylight Time, DAVELEIKAM@wi.rr.com writes: Should we or has anyone installed a trim power disconnect of some sort? >>> Already done- it's called the "Master Switch". First indication of a trim runaway and this puppy gets nailed. Trim is on Main Bus, so it dies as fast as you can react. E-bus for remainder of flight. Mark Phillips - Z-11 RV-6A _http://websites.expercraft.com/n51pw/_ (http://websites.expercraft.com/ n51pw/) (http://websites.expercraft.com/n51pw) ************************************** See what's free at http://www.aol.com. ________________________________ Message 2 _____________________________________ Time: 07:01:04 AM PST US Subject: Re: AeroElectric-List: Runaway trim From: "Valovich, Paul" I intend to have both roll trim and pitch trim disconnect switches on the side panel. However, more importantly, during the test phase I will fly with full nose up / nose down trim. Paul Valovich RV-8A N192NM (Reserved) ________________________________ Message 3 _____________________________________ Time: 08:02:02 AM PST US From: "Fergus Kyle" Subject: AeroElectric-List: Runaway trim A circuit breaker is not an emergency switch. Looking for it on the panel is not a good idea when the aircraft may be going out of control. A critical question to ask when searching for a kit/project is: 'Can this design be flown when at the extremes of trim range?' If not, it should be shunned. That is a criterion most required of any design with relatively limited speed range. If so, then time is available to plan for a safe landing under the circumstances. At least there is little need to panic - if in automatic flight, disconnect and handfly. If not, the fastest reaction is your (already-) attached hand. Engine failure on take-off and runaway trim are perhaps the two most demanding failures. On every takeoff one should be spring-loaded to expect the engine to quit. The exhilaration of a successful takeoff is the knowledge the engine didn`t quit! If runaway trim is too rapid to react to, then the trim motor needs slowing....... Happy landings Ferg Europa A064 ________________________________ Message 4 _____________________________________ Time: 08:35:48 AM PST US Subject: Re: AeroElectric-List: Isolated DC-DC Electronics design pointers From: Ron Quillin At 20:19 6/6/2007, you wrote: > I have attached a schematic and photo's of the 9VDC ANR supply I > have built for my RV7A (Headsets Inc ANR conversion) I have tested > the supply for basic DC voltage. I Shouldn't converter pin 7 in your schematic be VOUT- ? Likely just an oversight/typo, but could confuse years later. Ron Q. ________________________________ Message 5 _____________________________________ Time: 08:44:30 AM PST US Subject: Re: AeroElectric-List: Runaway trim From: Ron Quillin At 22:00 6/6/2007, you wrote: >Should we or has anyone installed a trim power disconnect of some >sort? After Attending Bob Nuckolls seminar and hearing his >reasons for not installing circuit breakers which I generally agree >with, would this be a reason for a pullable breaker on this >circuit? What do you guys and gals think? Many certified A/P and electric trim systems have multiple means to effect an emergency disconnect. A Century Flight Systems system with which I am quite familiar has three: 1) yoke mounted momentary disconnect/override 2) panel mounted on/off toggle switch; one each for A/P and trim 3) panel mounted pullable circuit breakers; one each for A/P and trim This is in addition to the mechanical trim control that can override the clutch of the system. Overkill, perhaps. But like I mentioned, it's a certified system in a certified aircraft. It does, however, provide redundancy; and points of failure... Ron Q. ________________________________ Message 6 _____________________________________ Time: 09:23:37 AM PST US Subject: RE: AeroElectric-List: First Start of my rotary From: "Hinde, Frank George (Corvallis)" Didn't say they don't work but the debate over how fast they go VS. how much fuel burn has never been proven to my knowledge...I.e water cooled engines have an inherrent disadvantage in that they have more drag to overcome. That can be done with careful ducting but it's a hard thing to do with the engine so close to the front. Has it been done on an RV?..I dunno,...Does it matter?...I.e if it costs 1 gallon per hour more in a Rotary coversion but the conversion is half price compared to a Lyc it may still be a good deal. Frank Do not archive -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Bob White Sent: Wednesday, June 06, 2007 3:46 PM Subject: Re: AeroElectric-List: First Start of my rotary Hi Frank, Better not tell all those guys flying RV's with rotary engines. Bob W. On Wed, 6 Jun 2007 20:58:14 -0000 "Hinde, Frank George (Corvallis)" wrote: > Indeed, although the web page is a little out of date as Experimental > Lyclones are now way cheaper than the 34K listed...More like 21 to 24k > for a brand new fuel injected IO360. > > The rotary is a fascinating conversion however (not good for a tractor > airplane due to the difficulty in getting long ducts to deal with the > cooling drag, but much more amenable to a pusher design I think. > > Good job > > Frank > > ________________________________ > > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of > longg@pjm.com > Sent: Wednesday, June 06, 2007 1:15 PM > To: aeroelectric-list@matronics.com > Subject: RE: AeroElectric-List: First Start of my rotary > > > Congratulations Chris, > A freshly minted non-smoking wiring system and a smooth running > rotary are proud milestones. > > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of > Christopher Barber > Sent: Wednesday, May 30, 2007 11:40 PM > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: First Start of my rotary > > > Just a quick note to announce the first starts of my 13b rotary > engine in my Velocity SE wired with Bob's Z-14 diagrams. Thanks for > the great info in the book and on this list. It provides a great deal > of piece of mind. If you are interested in more details check out my > posts or those of my buddy David Staten who is helping me in the > build, on www.canardaviation.com or the flyrotary email list. Thanks Bob. > > All the best, > > Chris > www.LoneStarVelocity.com > Houston, Texas > > > > href="http://www.matronics.com/Navigator?AeroElectric-List">http://www > .m atronics.com/Navigator?AeroElectric-List > href="http://forums.matronics.com">http://forums.matronics.com > > > > > > > > -- N93BD - Rotary Powered BD-4 - http://www.bob-white.com 3.8 Hours Total Time and holding Cables for your rotary installation - http://www.roblinphoto.com/shop/ ________________________________ Message 7 _____________________________________ Time: 09:23:37 AM PST US Subject: Re: AeroElectric-List: Runaway trim From: john@ballofshame.com What anyone should take away from ANY discussion of fuses, switches and breakers is: "Use the right tool for the right job." It seems perfectly reasonable to me to use a switchable breaker like a Klixon (my favorite) or a P&B for things which you may want to switch off for regular maintenance or emergencies. Alternator field, electric trim and electric flaps seem like a very good use for a breaker. Another thing to consider which I haven't seen anyone do is a warning tone whenever the trim or flaps are energized. Low pitch for trim...hi for flaps...something like that. You could also install a blinky light right next to the breaker that controls the piece of equipment in question. This would be trivial as you'd just take power right at the breaker. Any time current flowed, the light would go on. So warning tone goes off, "Hey, I'm not moving the trim!!", look over and yank the breaker with the blinky light. Bad idea? Maybe. It's not a suggestion...just food for thought. While it's nice to think that most of us would catch a runaway trim or flap motor, and then just do the right thing because we're all trained and proficient, the reality is that the pilot is not only the most flexible and capable part of the system but also often the weak link esp. when things go wrong. Systems should be balanced to both be efficient AND give the pilot every advantage. my $.02 -John www.ballofshame.com ________________________________ Message 8 _____________________________________ Time: 11:00:08 AM PST US From: Buckaroo Banzai Subject: Re: AeroElectric-List: Runaway trim Cessna used to use a split switch for electric trim (they might still but I don't have any recent experience with Cessnas) so that two failures would have to occur to get runaway trim. Of course, you should also make sure the wiring from each of the switches is isolated from the other and the trim power relays are isolated from each other (physical separation or barriers) to prevent a short across both switches or relays. Greg Dave Leikam wrote: A few days ago a Citation jet carrying a crew of two and 4 medical personnel including organ transplant doctors, went down in Lake Michigan just off shore from Milwaukee, WI shortly after takeoff. The pilot declared an emergency due to severe control problems and was cleared to return to MKE. No survivors. First my condolences to the families and friends. Next, preliminary reports are that the crash may have been due to "Runaway trim." Our RV-10s have electric trim. Should we or has anyone installed a trim power disconnect of some sort? I realize that the forces to overcome full trim on the 10 are not as great as a Citation, but would this be prudent? After Attending Bob Nuckolls seminar and hearing his reasons for not installing circuit breakers which I generally agree with, would this be a reason for a pullable breaker on this circuit? What do you guys and gals think? Mr. Nuckolls, how about your thoughts? Dave Leikam 40496 RV-10 QB Wings --------------------------------- Moody friends. Drama queens. Your life? Nope! - their life, your story. Play Sims Stories at Yahoo! Games. ________________________________ Message 9 _____________________________________ Time: 11:07:09 AM PST US From: Ernest Christley Subject: Re: AeroElectric-List: First Start of my rotary Hinde, Frank George (Corvallis) wrote: > > Didn't say they don't work but the debate over how fast they go VS. how > much fuel burn has never been proven to my knowledge...I.e water cooled > engines have an inherrent disadvantage in that they have more drag to > overcome. That can be done with careful ducting but it's a hard thing to > do with the engine so close to the front. > > Water cooled engines have an inherent advantage in that they don't have to have the radiator up front just because that is where the engine is. Here's a picture of my oil cooler arrangement. The radiator is on the other side. Tractor configuration. Picture is from the front of the airplane. The black triangle up front is part of the firewall. http://www.ernest.isa-geek.org/Delta/Pictures/OilCoolerDuctFront.jpg Advantages: Better weight and balance configuration. NACA studies indicate that my inlet and outlet placement will provide the least drag of any cooling arrangement except for jets or rockets. The fuel burn question will never be answered, IMHO, regardless of how much data you provide showing the rotary gobbles gas if you try to fly it like a Lycoming, but the difference falls into the noise when you fly it like a rotary. The BSFC goes through the roof when the mixture is configured for best power (the only regime anyone seems to care about on a dyno), but stays quite reasonable when properly leaned for a power regime that keeps the plane under Vne. To complicated for most, I guess. I give up. The doubters win. I'll just tell people that I have secret tanks concealed with a cloaking device and levitated with my anti-gravity pixie-dust so that the fuel it contains doesn't add to the airplane's gross weight. The extra fuel is delivered at night by secret-ops Federal Marshalls under the direct supervision of the CEO of Exxon, because I know of some dirty secrets on Dick Cheney's good-ol'-boy network. That should be a much more convincing story of why all the rotary powered aircraft seem to have the same range as their Lycoming powered brethren. To bring this back on topic for this discussion list, the rotary has another advantage in that the output shaft is turning at 6000RPM or so at cruise. Just about right for a direct-drive generator. With a PM rotor mounted directly to the shaft, there's no need for belts or gears. No weight needed for a heavy case or robust and heavy mounting brackets. In a tractor configuration, it will be constantly impacted by fresh cooling air. ________________________________ Message 10 ____________________________________ Time: 11:38:58 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Runaway trim At 09:22 AM 6/7/2007 -0700, you wrote: > >What anyone should take away from ANY discussion of fuses, switches and >breakers is: > >"Use the right tool for the right job." > >It seems perfectly reasonable to me to use a switchable breaker like a >Klixon (my favorite) or a P&B for things which you may want to switch off >for regular maintenance or emergencies. Alternator field, electric trim >and electric flaps seem like a very good use for a breaker. > >Another thing to consider which I haven't seen anyone do is a warning tone >whenever the trim or flaps are energized. Low pitch for trim...hi for >flaps...something like that. You could also install a blinky light right >next to the breaker that controls the piece of equipment in question. >This would be trivial as you'd just take power right at the breaker. Any >time current flowed, the light would go on. So warning tone goes off, >"Hey, I'm not moving the trim!!", look over and yank the breaker with the >blinky light. Bad idea? Maybe. It's not a suggestion...just food for >thought. > >While it's nice to think that most of us would catch a runaway trim or >flap motor, and then just do the right thing because we're all trained and >proficient, the reality is that the pilot is not only the most flexible >and capable part of the system but also often the weak link esp. when >things go wrong. Systems should be balanced to both be efficient AND give >the pilot every advantage. There are many, Many, MANY approaches to building firewalls against the undesirable. The task is first to see if a firewall is even necessary. Finally, the elegant solution calls for a minimum parts count solution with low cost of ownership and minimizing probability that "Plan-B" for pitch trim failure is not more likely to be a maintenance problem than the pitch trim system being monitored/ protected. See: http://www.aeroelectric.com/articles/Trim_System_Failures.pdf Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ---------------------------------------- ________________________________ Message 11 ____________________________________ Time: 01:47:35 PM PST US From: Kevin Horton Subject: Re: AeroElectric-List: Runaway trim On 7 Jun 2007, at 00:00, Dave Leikam wrote: > A few days ago a Citation jet carrying a crew of two and 4 medical > personnel including organ transplant doctors, went down in Lake > Michigan just off shore from Milwaukee, WI shortly after takeoff. > The pilot declared an emergency due to severe control problems and > was cleared to return to MKE. No survivors. First my condolences > to the families and friends. Next, preliminary reports are that > the crash may have been due to "Runaway trim." Our RV-10s have > electric trim. Should we or has anyone installed a trim power > disconnect of some sort? I realize that the forces to overcome > full trim on the 10 are not as great as a Citation, but would this > be prudent? After Attending Bob Nuckolls seminar and hearing his > reasons for not installing circuit breakers which I generally agree > with, would this be a reason for a pullable breaker on this > circuit? What do you guys and gals think? Mr. Nuckolls, how about > your thoughts? > If you have electric trim, you should set do flight testing to confirm that you can handle a full travel trim runaway at high speed. You can minimize the stick forces by setting the trim travel to the minimum required to trim off forces in the two extreme cases (VNE at aft CG and approach speed at forward CG). If a trim runaway happens, you can minimize the amount of mistrim by having a quick way to remove power from the trim, but it needs to be something that you can find and actuate very quickly. I've got a big red button on my stick grip. Pushing and holding that button removes power from the trim and wing leveler. I then would turn off the power switch for trim or wing leveler, and release the big red button. Kevin Horton RV-8 (Finishing Kit) Ottawa, Canada http://www.kilohotel.com/rv8 ________________________________ Message 12 ____________________________________ Time: 01:47:39 PM PST US From: Kevin Horton Subject: Re: AeroElectric-List: Runaway trim On 7 Jun 2007, at 08:59, Valovich, Paul wrote: > However, more importantly, during the test phase I will fly with > full nose up / nose down trim. The worst case failures to look at for this test would likely be: CG at the aft limit, VNE, full nose up trim runway, and CG at the forward limit, flaps down, approach speed, full nose down trim runaway. Areas of interest to investigate during the tests: Starting from an in-trim condition, and holding the trim switch, but letting the aircraft respond naturally - how long do you have to react before a dangerous condition results? Are you comfortable that you would always react that quickly? If not, maybe the trim rate should be slowed down. As a reference, for transport category aircraft, it is expected that the crew could delay their reaction for up to three seconds in cruise without a dangerous condition being reached. On final approach, it is assumed that the crew will react within one second. What are the stick forces required once you react to the failure by applying a stick force to counter the aircraft pitching motion? Are you comfortable that you could hold this high a stick force for the time required to get the aircraft on the ground? Could you fly a safe landing holding this much stick force? How should you fly the approach following this failure (which flap angle and approach speed)? If the runway is nose down, the stick forces might be lighter if you do an approach with the flaps up, and a bit higher speed than normal. Kevin Horton RV-8 (Finishing Kit) Ottawa, Canada http://www.kilohotel.com/rv8 ________________________________ Message 13 ____________________________________ Time: 01:52:24 PM PST US From: "Doug Windhorn" Subject: Re: AeroElectric-List: Runaway trim Not about to become in the probability or need of trim system interrupts, but since it is of some concern, the following approach might be of interest to some (those not tied to the dual stick coolie hat switches). This is from another web list, and is a modification I will make to my system on the next wiring go-around. First, use only one trim input point such as on the panel, one on each stick aggravates the possibility of unwanted trim travel, either accidentally, or through cross-inputting. That location of the switches would be available to both pilot/copilot in a side by side seating. This may eliminate the need for relays (except for switch wear). Use two (on)-off-(on) rocker switches, installed side by side. The 1st switch is the power control switch. The 2nd switch is the servo control switch. Both must be activated simultaneously to move the servo. Wire the outputs [(on)] of the first switch to together and input to the 2nd switch [off] and any relays or other components in the trim system needing power. Unless the power switch is moved to either (on) position, there is no power to the trim system and it should not go anywhere; no need to get into a reactive situation, or have a pullable breaker. Doug Windhorn ----- Original Message ----- From: Sent: Thursday, 07 June, 2007 9:22 Subject: Re: AeroElectric-List: Runaway trim > > What anyone should take away from ANY discussion of fuses, switches and > breakers is: > > "Use the right tool for the right job." > > It seems perfectly reasonable to me to use a switchable breaker like a > Klixon (my favorite) or a P&B for things which you may want to switch off > for regular maintenance or emergencies. Alternator field, electric trim > and electric flaps seem like a very good use for a breaker. > > Another thing to consider which I haven't seen anyone do is a warning tone > whenever the trim or flaps are energized. Low pitch for trim...hi for > flaps...something like that. You could also install a blinky light right > next to the breaker that controls the piece of equipment in question. > This would be trivial as you'd just take power right at the breaker. Any > time current flowed, the light would go on. So warning tone goes off, > "Hey, I'm not moving the trim!!", look over and yank the breaker with the > blinky light. Bad idea? Maybe. It's not a suggestion...just food for > thought. > > While it's nice to think that most of us would catch a runaway trim or > flap motor, and then just do the right thing because we're all trained and > proficient, the reality is that the pilot is not only the most flexible > and capable part of the system but also often the weak link esp. when > things go wrong. Systems should be balanced to both be efficient AND give > the pilot every advantage. > > my $.02 > > -John > www.ballofshame.com > > > ________________________________ Message 14 ____________________________________ Time: 02:36:12 PM PST US From: Kevin Horton Subject: Re: AeroElectric-List: Runaway trim On 7 Jun 2007, at 15:47, Doug Windhorn wrote: > Use two (on)-off-(on) rocker switches, installed side by side. The > 1st switch is the power control switch. The 2nd switch is the > servo control switch. Both must be activated simultaneously to move > the servo. Wire the outputs [(on)] of the first switch to together > and input to the 2nd switch [off] and any relays or other > components in the trim system needing power. Unless the power > switch is moved to either (on) position, there is no power to the > trim system and it should not go anywhere; no need to get into a > reactive situation, or have a pullable breaker. > If you go down this road, you should add a first flight of the day ground test to confirm that the power switch has not failed in the hot position. This would be a dormant failure, which would defeat the protection provided by this design, and would only be detected by a specific test. Kevin Horton RV-8 (Finishing Kit) Ottawa, Canada http://www.kilohotel.com/rv8 ________________________________ Message 15 ____________________________________ Time: 03:52:04 PM PST US From: Ralph Hoover Subject: Re: AeroElectric-List: Isolated DC-DC Electronics design pointers Ron, Good catch. Thanks! Here is a revised PDF. -- Ralph C. Hoover RV7A hooverra at verizon dot net ________________________________ Message 16 ____________________________________ Time: 05:17:21 PM PST US From: Glen Matejcek Subject: AeroElectric-List: Re: Runaway trim Hi Dave- RE: After Attending Bob Nuckolls seminar and hearing his reasons for not installing circuit breakers which I generally agree with, would this be a reason for a pullable breaker on this circuit? What do you guys and gals think? Mr. Nuckolls, how about your thoughts? For my part, on my -8, which is of course a tandem, I do have a way to defeat the trim. My original concern was to be able to render the aft trim inop should someone back there do something innapropriate. One thing led to another, and what I have now is a progressive switch wired up to manage the trim system. The way it's configured, in the up position the grounds from both MAC stick grips are connected to the ground bus and the whole sys is operative. In the central position, the fwd stick still grounds, but the aft is isolated. In the down position, only the fwd PTT still grounds. This way I can protect against errors in the back as well as a runaway with the flick of one switch. FWIW- gm Glen Matejcek ________________________________ Message 17 ____________________________________ Time: 06:24:26 PM PST US From: "Michel Creek" Subject: AeroElectric-List: JJN 80 Amp "Boltable" Fuse Source Does anyone know a good source for a JJN/JJS style 80 amp "boltable" fuse? I'm wiring a 60 amp alternator per Z-22, but I can't seem to locate the right fuse to wire in-line between the alternator and starter leads. I've checked B&C and AC Spruce. Thanks, Mike C. ________________________________ Message 18 ____________________________________ Time: 06:43:13 PM PST US From: "Michael T. Ice" Subject: Re: AeroElectric-List: JJN 80 Amp "Boltable" Fuse Source Michel, www.marineengineparts.com/shopsite_sc/store/html/page223.html Is this the type of fuse you are looking for? Mike ----- Original Message ----- From: "Michel Creek" Sent: Thursday, June 07, 2007 5:21 PM Subject: AeroElectric-List: JJN 80 Amp "Boltable" Fuse Source > > > Does anyone know a good source for a JJN/JJS style 80 amp "boltable" fuse? > I'm wiring a 60 amp alternator per Z-22, but I can't seem to locate the > right fuse to wire in-line between the alternator and starter leads. I've > checked B&C and AC Spruce. > > Thanks, > Mike C. > > > ________________________________ Message 19 ____________________________________ Time: 07:02:26 PM PST US From: "Michel Creek" Subject: RE: AeroElectric-List: JJN 80 Amp "Boltable" Fuse Source Thanks Mike. Those would work if they can be used in-line with a 4 awg cable in about an 8-inch run. There isn't anyplace to mount an ANL type base so the fuse must be strong enough in tension to survive in the high vibration environment between the alternator and starter. Searching the archives, Bob made reference to a JJN/JJS style "boltable" fuse for that application. Do Not Archive ------------------------------------------------------------------------ Michel, www.marineengineparts.com/shopsite_sc/store/html/page223.html Is this the type of fuse you are looking for? Mike > > Does anyone know a good source for a JJN/JJS style 80 amp "boltable" fuse? > I'm wiring a 60 amp alternator per Z-22, but I can't seem to locate the > right fuse to wire in-line between the alternator and starter leads. I've > checked B&C and AC Spruce. > > Thanks, > Mike C. ________________________________ Message 20 ____________________________________ Time: 07:15:16 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Runaway trim Thanks to the welcome attention of a few readers on the List, I've updated the article below to fix some wording . . . and modified the schematic to make installation and operation easier and more logical. Interested parties can get revision A at: http://www.aeroelectric.com/articles/Trim_System_Failures.pdf Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ---------------------------------------- ________________________________ Message 21 ____________________________________ Time: 08:04:07 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: JJN 80 Amp "Boltable" Fuse Source At 06:21 PM 6/7/2007 -0700, you wrote: > > >Does anyone know a good source for a JJN/JJS style 80 amp "boltable" fuse? >I'm wiring a 60 amp alternator per Z-22, but I can't seem to locate the >right fuse to wire in-line between the alternator and starter leads. I've >checked B&C and AC Spruce. We discontinued that fuse when it proved less robust mechanically than we would have liked. The recommended replacement is the ANL series current limiters. Better yet, consider the Littlefuse MEGA series fuses. See: https://www.vtewarehouse.com/content/electromech/fuse/html/mega/megafuse.php These are smaller and less expensive than the ANL devices. Another option is the MAXI fuse which is also available with an in-line holder at: https://www.vtewarehouse.com/content/electromech/fuse/html/maxi/maxifuse.php Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ---------------------------------------- ________________________________ Message 22 ____________________________________ Time: 08:52:37 PM PST US From: Joemotis@aol.com Subject: Re: AeroElectric-List: JJN 80 Amp "Boltable" Fuse Source Bob, as a long time lurker and a former 68F20/68F30 I would like to thank you for the personal knowledge you share so unselfishly. The knowledge base that you have earned and so generously share is immeasurable in it's contribution to the advancement of Aviation. JJN/JJS indeed. Joe Motis I.B.E.W. Local 11 Special Skills Electrician 601 XL Do not archive ************************************** See what's free at http://www.aol.com. ________________________________ Message 23 ____________________________________ Time: 08:58:51 PM PST US From: Joemotis@aol.com Subject: Re: AeroElectric-List: JJN 80 Amp "Boltable" Fuse Source And it's=its when you proofread after the fact... ************************************** See what's free at http://www.aol.com. ________________________________ Message 24 ____________________________________ Time: 09:11:35 PM PST US From: Fiveonepw@aol.com Subject: AeroElectric-List: Annunciator HELP! This post is for the techno-weenies- all others delete NOW! Goal: Illuminate an annunciator light when TruTrak servos are OFF using NKK LB series illuminated pushbutton: _http://rocky.digikey.com/scripts/ProductInfo.dll?Site=US&V=360&M=LB25RKW01-5C -JC-RO_ (http://rocky.digikey.com/scripts/ProductInfo.dll?Site=US&V=360&M=LB25RKW01-5C-JC-RO) This device is a DPDT PB with LED lamp, built-in resistor for the LED. (Reason for using PB instead of simple lamp is provide built-in PTT function with N.O. contacts. LED has its own +&- contacts on back of switch) Consultation with TruTrak reveals that the torque line (pin6) to either servo can be used to sense when power is applied to the servo, thereby providing the necessary input. They sent a drawing showing a 10K resistor tied to this pin gating on a darlington transistor to provide the switch (ground path) for a lamp. Good, but I need the light OFF when power is on this pin. Please don't ask why, this is what I want to happen. I begged the list for guidance some time ago and Bob very generously supplied sketches (THANKS!) for how to achieve this using a IRF510 MOSFET to either (1) turn the lamp ON as TruTrak indicated, or (2) turn the lamp OFF by connecting the MOSFET between a 470 ohm resistor supplying the LED and ground, which I understand would essentially remove voltage from the LED by shorting its supply voltage to ground. With 13 volts supplied, this would be about 30mA through the MOSFET when it is gated on, probably not resulting in a new-clee-ur event. Problem is, I assume Bob is referring to the resistor normally used to control LED current and since in the LB series switches this resistor is built into the LED, connecting the MOSFET to the LED supply voltage would essentially result in a dead short (minus MOSFET internal resistance) to ground. I'd surmise Mr. MOSFET would melt? Unless there is a more elegant solution, I suppose I could use the MOSFET to ground a relay coil and use NC contacts to operate the LED, which in my electronically-challenged understanding of this would get the job done. But even after hours of googling to understand these MOSFET monsters these questions remain: What are the connections to this beast? "Gate" I understand- signal from servo to gate on MOSFET. But what the heck are the "Source" (pin opposite gate) and "Drain" (center pin)? I'm supposing "source" in this case would be connection to the relay coil and "drain" is ground. Correct? One place I looked (WebEE?) indicates the mounting flange for the MOSFET (TO-220 pkg) is common to "drain" so that makes sense if the thing is mounted to the airframe. But another source said to insulate this from ground. (?) Another speaks of monster heatsinks, but I seriously doubt the coil current (75mA) of the relay of choice (Omron LY2F) would make the MOSFET break a sweat... If you managed to hang on this far, I'd sure appreciate some guidance- and if y'all got a better mousetrap, I'm willing to stick my neck out! Thanks and let's spare the archives with a do not archive thingie- Mark (I grok batteries....maybe) Phillips ************************************** See what's free at http://www.aol.com. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.