---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 04/18/22: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:54 AM - Re: CB polarity? (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 10:54:39 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: CB polarity? At 09:08 PM 4/17/2022, you wrote: >"johnbright" > >I'm not using this type of breaker but >curious why is it marked for polarity? There is a constellation of reasons for marking the input and output connections for breakers, switches and relays. On of many explanations can be found here: https://tinyurl.com/y5zge76c Standardization specs call for marking terminals on such devices if it 'makes a difference'. Instances where it does make a difference includes specialy breakers with internal features beyond the rudimentary need to protect a wire from fault damage. A manufacturer can choose not to mark inputs and outputs if their device doesn't care . . . or if they want to avoid a qualification test that demonstrates tolerance to a reversed flow. In small breakers typical of applications in aviation, the LINE/LOAD labels would be significant only if there's a third terminal common to specialized electronics inside the breaker (soft fault detection, remote trip, etc). Bob . . . Un impeachable logic: George Carlin asked, "If black boxes survive crashes, why don't they make the whole airplane out of that stuff?" ------------------------------------------------------------------------------------- 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.