---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 06/06/15: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:58 AM - Re: power supply for testing (A R Goldman) 2. 04:46 AM - Re: power supply for testing (user9253) 3. 09:24 AM - Re: Alternator with no battery? (D L Josephson) 4. 03:53 PM - Re: Lighted Toggle Switch recommendation (haribole) 5. 04:19 PM - Re: Re: power supply for testing (ARGOLDMAN@aol.com) ________________________________ Message 1 _____________________________________ Time: 03:58:56 AM PST US Subject: Re: AeroElectric-List: power supply for testing From: A R Goldman What about a power supply from an old computer? Thanks Rich Sent from my iPhone > On Jun 4, 2015, at 1:41 PM, "Robert L. Nuckolls, III" wrote: > > At 10:09 AM 6/4/2015, you wrote: >> Would this item be an acceptable choice for testing my electrical system? Could it be used without any battery in the system? My avionics etc. are al l Dynon. >> >> http://www.amazon.com/Universal-Regulated-Switching-Computer-Project/dp/B 00D7CWSCG/ref=sr_1_5?ie=UTF8&qid=1433430384&sr=8-5&keywords=12+vol t+DC+power+supply&pebp=1433430415435&perid=1MV8XVM71ACD3B1WWBYZ >> >> Thanks, >> >> Ken > > > Yes > > > Bob . . . > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 2 _____________________________________ Time: 04:46:50 AM PST US Subject: AeroElectric-List: Re: power supply for testing From: "user9253" > What about a power supply from an old computer? > Thanks > Rich A computer power supply could be used, but be careful with polarity. A computer power supply has both positive and negative outputs. The negative output has a much smaller output rating, so use the positive output. A computer power supply voltage is only 12 volts, whereas an aircraft usually operates between 13 and 14 volts. But that should not matter for most equipment. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=443127#443127 ________________________________ Message 3 _____________________________________ Time: 09:24:09 AM PST US From: D L Josephson Subject: AeroElectric-List: Re: Alternator with no battery? On 6/6/15 12:00 AM, AeroElectric-List Digest Server wrote: > Time: 01:53:19 PM PST US > Subject: AeroElectric-List: Re: Alternator with no battery? > From: "donjohnston" > > > This is very interesting. Thanks to everyone for participating. > > So is it safe to say that the battery is providing a type of surge suppression > (or power leveling or fluctuation dampening) function in this circuit? Yes. > > And if it's correct that the absence of the battery could cause an over voltage > situation, is there a way to mitigate that? Or is that scenario so unlikely that > it's not worth protecting against? > There is a way to mitigate that, if you want. An overvoltage protection circuit can take a runaway alternator/regulator offline in the case of an open battery. This is probably a less likely possibility at least for lead-acid batteries than the possibility of the OVP taking the alternator offline at inconvenient times for other reasons. Systems engineering is based on understanding and weighing all of the foreseeable consequences -- more protection does not necessarily equate to fewer failure experiences. As Bob has explained in the past, modern aircraft loads are much more tolerant of overvoltage conditions than was the case years ago. Having had such an experience in my Mooney when the regulator ground wire came loose, I can report that it was preferable to manually shed loads known to be voltage-sensitive (no DME for you today!), add additional loads like pitot heat and landing lights to bring the voltage down. You can manage the situation, rather than pop the alternator offline (particularly automatically, with no possibility for reset) and trust the battery to supply the energy for the remainder of the flight. David Josephson ________________________________ Message 4 _____________________________________ Time: 03:53:53 PM PST US Subject: AeroElectric-List: Re: Lighted Toggle Switch recommendation From: "haribole" Digikey part number 432-1283-ND for the Carlington LT series seems like a good fit for 15A and under. http://tinyurl.com/q9o57pu Read this topic online here: http://forums.matronics.com/viewtopic.php?p=443150#443150 ________________________________ Message 5 _____________________________________ Time: 04:19:50 PM PST US From: ARGOLDMAN@aol.com Subject: Re: AeroElectric-List: Re: power supply for testing Thanks Joe Rich In a message dated 6/6/2015 11:10:47 A.M. Central Daylight Time, fransew@gmail.com writes: --> AeroElectric-List message posted by: "user9253" > What about a power supply from an old computer? > Thanks > Rich A computer power supply could be used, but be careful with polarity. A computer power supply has both positive and negative outputs. The negative output has a much smaller output rating, so use the positive output. A computer power supply voltage is only 12 volts, whereas an aircraft usually operates between 13 and 14 volts. But that should not matter for most equip ment. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=443127#443127 ------------------------------------------------------------------------------------- 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.