---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 03/31/19: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:28 AM - ov warning light (bobnoffs) 2. 05:17 PM - Re: ov warning light (Robert L. Nuckolls, III) 3. 07:35 PM - Re: ov warning light (bob noffs) 4. 07:46 PM - Re: ov warning light (Charlie England) ________________________________ Message 1 _____________________________________ Time: 05:28:26 AM PST US Subject: AeroElectric-List: ov warning light From: "bobnoffs" hi all, i put together an ov'crowbar ' for the output side of my alternator but in the end i didn't use it. instead i made a warning light from a 2.2v 20ma. led, 3 resistors totaling 1700 ohms and a 13v zenor diode. at 14v it very faintly glows which is good to see that it is working. at 15.06 v it glows brightly. not much difference between 10ma. and 20ma. in brightness so i have some leeway up to 30 volts. this warning is to protect 2 earthx batteries. whether or not i need it is a question but i gotta do something with that hole in the panel. bob noffs Read this topic online here: http://forums.matronics.com/viewtopic.php?p=488374#488374 ________________________________ Message 2 _____________________________________ Time: 05:17:03 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: ov warning light At 07:27 AM 3/31/2019, you wrote: > >hi all, > i put together an ov'crowbar ' for the output side of my > alternator but in the end i didn't use it. instead i made a warning > light from a 2.2v 20ma. led, 3 resistors totaling 1700 ohms and a > 13v zenor diode. at 14v it very faintly glows which is good to see > that it is working. at 15.06 v it glows brightly. not much > difference between 10ma. and 20ma. in brightness so i have > some leeway up to 30 volts. this warning is to protect 2 earthx > batteries. whether or not i need it is a question but i gotta do > something with that hole in the panel. EarthX battery BMS will protect the batteries. The BMS will not protect your avionics. If the BMS DISCONNECTS the battery from a runaway alternator, the bus voltage climbs at a VERY rapid rate. Unless your ov warning is BRIGHT, SUNLIGHT VIEWABLE, and FLASHES to trigger your Japanese kick boxer-reflexes . . . chances for making lots of transistor-toast is significant . . . but the batteries will be fine. Bob . . . ________________________________ Message 3 _____________________________________ Time: 07:35:20 PM PST US From: bob noffs Subject: Re: AeroElectric-List: ov warning light hi bob, yea, i know. and all i am doing it for is the batteries. after asking a lot of questions about this over several months it seems hardly anyone is doing anything to protect transistors. bob noffs On Sun, Mar 31, 2019 at 7:21 PM Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > At 07:27 AM 3/31/2019, you wrote: > > > hi all, > i put together an ov'crowbar ' for the output side of my alternator but > in the end i didn't use it. instead i made a warning light from a 2.2v > 20ma. led, 3 resistors totaling 1700 ohms and a 13v zenor diode. at 14v it > very faintly glows which is good to see that it is working. at 15.06 v it > glows brightly. not much difference between 10ma. and 20ma. in brightness > so i have some leeway up to 30 volts. this warning is to protect 2 earthx > batteries. whether or not i need it is a question but i gotta do something > with that hole in the panel. > > > EarthX battery BMS will protect the > batteries. The BMS will not protect > your avionics. If the BMS DISCONNECTS > the battery from a runaway alternator, > the bus voltage climbs at a VERY rapid > rate. > > Unless your ov warning is BRIGHT, SUNLIGHT > VIEWABLE, and FLASHES to trigger your > Japanese kick boxer-reflexes . . . chances > for making lots of transistor-toast is > significant . . . but the batteries > will be fine. > > > Bob . . . > ________________________________ Message 4 _____________________________________ Time: 07:46:11 PM PST US Subject: Re: AeroElectric-List: ov warning light From: Charlie England Hi Bob, Who are you asking? :-) Charlie On 3/31/2019 9:33 PM, bob noffs wrote: > hi bob, > yea, i know. and all i am doing it for is the batteries. after asking > a lot of questions about this over several months it seems hardly > anyone is doing anything to protect transistors. > bob noffs > > On Sun, Mar 31, 2019 at 7:21 PM Robert L. Nuckolls, III > > > wrote: > > At 07:27 AM 3/31/2019, you wrote: >> > >> >> hi all, >> i put together an ov'crowbar ' for the output side of my >> alternator but in the end i didn't use it. instead i made a >> warning light from a 2.2v 20ma. led, 3 resistors totaling 1700 >> ohms and a 13v zenor diode. at 14v it very faintly glows which is >> good to see that it is working. at 15.06 v it glows brightly. not >> much difference between 10ma. and 20ma. in brightness so i have >> some leeway up to 30 volts. this warning is to protect 2 earthx >> batteries. whether or not i need it is a question but i gotta do >> something with that hole in the panel. > > EarthX battery BMS will protect the > batteries. The BMS will not protect > your avionics. If the BMS DISCONNECTS > the battery from a runaway alternator, > the bus voltage climbs at a VERY rapid > rate. > > Unless your ov warning is BRIGHT, SUNLIGHT > VIEWABLE, and FLASHES to trigger your > Japanese kick boxer-reflexes . . . chances > for making lots of transistor-toast is > significant . . . but the batteries > will be fine. > > > Bob . . . > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ------------------------------------------------------------------------------------- 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.