---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 05/24/18: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:37 AM - Re: Low Battery Voltage Blows Fuel Pump Fuse? (user9253) 2. 01:55 PM - Re: Re: Low Battery Voltage Blows Fuel Pump Fuse? (Robert L. Nuckolls, III) 3. 10:14 PM - Noisy Alternator? (Paul Millner) ________________________________ Message 1 _____________________________________ Time: 04:37:22 AM PST US Subject: AeroElectric-List: Re: Low Battery Voltage Blows Fuel Pump Fuse? From: "user9253" The original poster has reported on VansAirforce that a new PC680 battery cured the fuel pump fuse blowing problem. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=480373#480373 ________________________________ Message 2 _____________________________________ Time: 01:55:46 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Low Battery Voltage Blows Fuel Pump Fuse? At 06:36 AM 5/24/2018, you wrote: > >The original poster has reported on VansAirforce that a new PC680 >battery cured the fuel pump fuse blowing problem. > >-------- Nothing like a repeatable experiment to add foundation to a theory. It seems that these pumps suffer anomalous behaviors during a brown-out condition. I.e. the the duration of the on-pulse to the solenoid winding exceeds normal expectations in duty-cycle limited coil current. The reason for brownout can be any combination of things including soggy battery, ship's wiring and/or architecture and excessive starter current. One easy fix would be to upsize the fuse. Recall that 20A won't burn a 22AWG wire . . . so increasing the pump fuse to 10A might just well be a reasonable work-around. Obviously, if the battery is getting soggy (do a load test) then replacing the battery is in order for a host of reasons. Also, moving the distribution feeder for the pump to the battery bus would bypass other voltage drops in ship's wiring and be in agreement with the philosophy of running all eletro-whizzies for electrically dependent engines from the battery bus. I've got one of those pumps around here somewhere left over from some energy studies about 20 years ago . . . haven't got time for a diligent hunt right now but if it turns up, I'll go to the bench to see if I can duplicate the behavior here. In the mean time, if anyone on the List can conduct the same experiment, it would be good data to gather. Speaking of bench supplies: There are some pretty attractive offers out there https://goo.gl/SD52Po https://goo.gl/vknsmw . . . at prices like these, everyone should have one. Bob . . . ________________________________ Message 3 _____________________________________ Time: 10:14:11 PM PST US Subject: AeroElectric-List: Noisy Alternator? From: Paul Millner After a couple of weeks of airplane downtime (we went to a birthday party in England via commercial transportation), my StrikeFinder lights up all the time now. Troubleshooting demonstrates that shutting down the alternator stops the apparent sparks. The problem persists after five hours of flying now. Is it most likely that my Ford alternator's brushes didn't like the hiatus, or coincidentally developed a problem? I've got a solid state regulator, PlanePower, so I don't envision it's causing the sparking. http://www.secure4host.net/upload/files/AlternatorStrikeFinder.jpg Paul ------------------------------------------------------------------------------------- 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.