---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 05/09/10: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:44 AM - Wire identification (Robert L. Nuckolls, III) 2. 06:49 AM - Re: Re: IVO Prop Motor Current Limiter and Electronic CB (Robert L. Nuckolls, III) 3. 07:10 AM - Re: Re: IVO Prop Motor Current Limiter and Electronic CB (Robert L. Nuckolls, III) 4. 06:16 PM - Re: IVO Prop Motor Current Limiter and Electronic CB (Dennis & Anne Glaeser) 5. 06:54 PM - Re: Re: IVO Prop Motor Current Limiter and Electronic CB (Robert L. Nuckolls, III) 6. 07:14 PM - Re: Re: IVO Prop Motor Current Limiter and Electron ic CB (n801bh@netzero.com) 7. 08:51 PM - Electric Boost Pump & Primer Switching (John Volkober) ________________________________ Message 1 _____________________________________ Time: 06:44:55 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Wire identification Comments/Questions: On the Power Distribution diagrams it doesn't show any special color for various wires. Just wondered, there are so many wires in even a small like my RV-4, should there be different colors for certain connections. I know RED is for power and BLACK is for ground but are other colors generally used for other connections or are all wires just considered either power or ground? The notion of marking wires with either colors or legends goes to the future task of troubleshooting. When you're installing wires, you pretty much know where they go and what they do. Further, there are so few wires total in a small aircraft that spending the $time$ to add any special identification to a wire adds little value in the future. Finally, wire is not cheap but buying in full spools or lots of 100' can save you some money. You don't want to have long spools of many colors that leaves you with a lot of left over wire at the end of your project. Suggest you go with what ever color (usually white) that makes sense economically. If you want to label some or all of them, consider paper labels held on the ends of the wire runs with clear heatshrink like . . . http://aeroelectric.com/Pictures/Wiring_Technique/Wire_Marking.jpg Bob . . . ________________________________ Message 2 _____________________________________ Time: 06:49:40 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: RE: IVO Prop Motor Current Limiter and Electronic CB At 10:20 PM 5/8/2010, you wrote: I made the original circuit that Bob posted. I got all the parts from DigiKey, including the IRFP 3703. I was finally able to test that circuit today. It worked exactly as predicted. With only the 0.1 ohm resistor, the current was limited to about 6 amps. This did not allow the motor to go as far as desired. So I added the parallel 0.5 ohm resistors one at a time. With both in place, it allows a bit over 8 amps, which is where the motor just starts to strain. This is also about the same place where the reed switch triggers. The mosfet does get rather warm, but only if the switch is held longer than normal. I've had a lot of folks become concerned with transistors that got "rather warm" but without puting some form of instrumentation on the device and then accounting for thermal resistances in the heat-energy transfer path, "rather warm" is a rather loose quantification term. There are instances where the surface temperature of a power device can get up to "sizzle-spit" temperatures and still be within operating limits. So if your finger-test of the device did not send you looking for the burn ointment, then there's a high probability that the transistor as installed and operated is going to be okay . . . I also plan to build the Electronic CB circuit. When it was published, Bob's said to wait until others had a chance to review and comment before building, so I haven't begun that process yet. Go ahead an 'brass-board' it if you can. I'm still to tied up with table saws and paint brushes to spend time at the bench. Do you have access to a 'scope? It would be interesting to fine-tune/verify the value of the capacitor to make the circuit trip in 200-500 milliseconds after the green light comes on. Thanks for your help in the development effort. Bob . . . ________________________________ Message 3 _____________________________________ Time: 07:10:18 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: RE: IVO Prop Motor Current Limiter and Electronic CB >I was finally able to test that circuit today. It worked exactly as >predicted. With only the 0.1 ohm resistor, the current was limited to about >6 amps. This did not allow the motor to go as far as desired. So I added the >parallel 0.5 ohm resistors one at a time. With both in place, it allows a >bit over 8 amps, which is where the motor just starts to strain. This is >also about the same place where the reed switch triggers. Hmmmm . . . for the final configuration you'll probably want to increase the current limit on up to 10A. Without knowing the modulus of elasticity of the prop materials with respect to temperature, you don't want to loose pitch-stroke because the current limit it set too low. So paralleling the .1 ohm with .2 ohms will produce a total of 1/(1/0.2 + 1/0.1)= 0.066 ohms which should boost the limit to just over 10A. Adding the 200-500 millisecond trip over ride should allow you to flirt at the edges of the 10 C/B value without tripping it. Bob . . . ________________________________ Message 4 _____________________________________ Time: 06:16:12 PM PST US From: "Dennis & Anne Glaeser" Subject: AeroElectric-List: RE: IVO Prop Motor Current Limiter and Electronic CB The mosfet does get rather warm, but only if the switch is held longer than normal. I've had a lot of folks become concerned with transistors that got "rather warm" but without putting some form of instrumentation on the device and then accounting for thermal resistances in the heat-energy transfer path, "rather warm" is a rather loose quantification term. There are instances where the surface temperature of a power device can get up to "sizzle-spit" temperatures and still be within operating limits. So if your finger-test of the device did not send you looking for the burn ointment, then there's a high probability that the transistor as installed and operated is going to be okay . . . ----> I didn't think to measure the mofset temp, but it definitely didn't get 'sizzle-spit' hot in my tests. I'm sure it could if the switch were held long enough. I'll measure temps at my next opportunity. ----- I also plan to build the Electronic CB circuit. When it was published, Bob's said to wait until others had a chance to review and comment before building, so I haven't begun that process yet. Go ahead an 'brass-board' it if you can. I'm still to tied up with table saws and paint brushes to spend time at the bench. Do you have access to a 'scope? It would be interesting to fine-tune/verify the value of the capacitor to make the circuit trip in 200-500 milliseconds after the green light comes on. ----> I will do that, but it will be a little while before I can get to it. Work and other commitments definitely get in the way of the fun stuff. I don't have a 'scope, but may be able to find one in my EAA chapter. ---- Thanks for your help in the development effort. Bob . . . ----> I'm the one who is the recipient of YOUR work :-) Dennis ________________________________ Message 5 _____________________________________ Time: 06:54:46 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: RE: IVO Prop Motor Current Limiter and Electronic CB At 08:13 PM 5/9/2010, you wrote: > > > Thanks for your help in the development effort. > > Bob . . . > >----> I'm the one who is the recipient of YOUR work :-) > > Dennis We all have a part to play. I can plant seeds but may not have the time to explore their value. If folks like you can pick up the ball and advance it down-field, then value has been added. Ultimately, we wish that others will benefit from the sum total of everyone's start- up efforts. THAT is how the gathering of simple-ideas gets vetted as a recipe for success. Folks on the List may recall numerous conversations in the past where a particular design philosophy was the target of vociferous bashing . . . while thousands of examples had been flying and performing as expected for two decades. What we do here may flop. It may be a ho-hum success. It may provide the idea-seeds for yet another quantum jump in capability or utility. But seeds never planted, nurtured and harvested will never reveal their value. Bob . . . ________________________________ Message 6 _____________________________________ Time: 07:14:00 PM PST US From: "n801bh@netzero.com" Subject: Re: AeroElectric-List: RE: IVO Prop Motor Current Limiter and Electron ic CB Thanks guys for experimenting in this area.... I have been through 1 Ivo motor so far and the current one is showing its age now... I am pretty anal about taking care not to drive the motor to its stall limit by usin g my ammeter to show increased amp draw, but this is kinda hard to do wi th my 80 amp alt keeping up with the load and masking the higher draw wh en stalled, or at least approaching it. The 'extra' noise from the V-8 u p front doesn't help either. . Tailwinds all.............. do not archive Ben Haas N801BH www.haaspowerair.com ---------- Original Message ---------- From: "Dennis & Anne Glaeser" Subject: AeroElectric-List: RE: IVO Prop Motor Current Limiter and Elect ronic CB rs@wideopenwest.com> The mosfet does get rather warm, but only if the switch is held longer t han normal. I've had a lot of folks become concerned with transistors that got "rather warm" but without putting some form of instrumentation on the device and then accounting for thermal resistances in the heat-energy transfer path, "rather warm" is a rather loose quantification term. There are instances where the surface temperature of a power device can get up to "sizzle-spit" temperatures and still be within operating limits. So if your finger-test of the device did not send you looking for the burn ointment, then there's a high probability that the transistor as installed and operated is going to be okay . . . ----> I didn't think to measure the mofset temp, but it definitely didn' t get 'sizzle-spit' hot in my tests. I'm sure it could if the switch were held long enough. I'll measure temps at my next opportunity. ----- I also plan to build the Electronic CB circuit. When it was published, B ob's said to wait until others had a chance to review and comment before building, so I haven't begun that process yet. Go ahead an 'brass-board' it if you can. I'm still to tied up with table saws and paint brushes to spend time at the bench. Do you have access to a 'scope? It would be interesting to fine-tune/verify the value of the capacitor to make the circuit trip in 200-500 milliseconds after the green light comes on. ----> I will do that, but it will be a little while before I can get to it. Work and other commitments definitely get in the way of the fun stuff. I don't have a 'scope, but may be able to find one in my EAA chapter. ---- Thanks for your help in the development effort. Bob . . . ----> I'm the one who is the recipient of YOUR work :-) Dennis ======================== =========== ======================== =========== ======================== =========== ======================== =========== ____________________________________________________________ #1 Oil & Gas Penny Stock PDGO - Paradigm Oil and Gas $800Million in Probable Oil Reserves http://thirdpartyoffers.netzero.net/TGL3241/4be76b7199fbc37d6fcst06vuc ________________________________ Message 7 _____________________________________ Time: 08:51:42 PM PST US From: "John Volkober" Subject: AeroElectric-List: Electric Boost Pump & Primer Switching This is my first post, so here we go. I want to have a single switch that controls my electric fuel pump and also allows me to activate my primer solenoid. The diagram below is my idea of on how this should work. I am using a S700-51 switch. In the first position, the electric fuel, pump in off. In the second position, the fuel pump is on. In the third position, a momentary position, both the fuel pump and the primer solenoid are on activating the primer. Will this work? Is there a another approach I should consider? John Volkober ------------------------------------------------------------------------------------- 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.