---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 01/19/20: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:49 AM - External socket to charge the airplane batteries (Carlos Trigo) 2. 11:35 AM - Re: External socket to charge the airplane batteries (Charlie England) 3. 01:18 PM - Re: External socket to charge the airplane batteries (Robert L. Nuckolls, III) 4. 02:29 PM - Re: External socket to charge the airplane batteries (Sebastien) ________________________________ Message 1 _____________________________________ Time: 10:49:22 AM PST US From: Carlos Trigo Subject: AeroElectric-List: External socket to charge the airplane batteries Guys In my RV-10 both batteries (main Batt - Odissey PC-925, and Aux Batt - Odiss ey PC-680) are in the back, inside the tail cone, behind the baggage compart ment. This is a difficult place to reach, in the completed airplane, to connect th e clamps of a battery charger/maintainer. Therefore I am going to install an external socket like this in the airplane skin, to be easy to connect the charger from the outside. I am thinking in connecting both batteries to this socket through a SPDT swi tch, to be able to select which battery to be charged. Now the questions: 1 - which is the current flowing through this socket when charging? 2 - consequently, which gauge of wires should be used (#18)? 3 - should I use any fuse in this circuit? If yes, which A? 4 - is there any possibility to charge both batteries at the same time? If yes, which is the smart way to achieve that? Thanks in advance Carlos ________________________________ Message 2 _____________________________________ Time: 11:35:44 AM PST US Subject: Re: AeroElectric-List: External socket to charge the airplane batteries From: Charlie England On 1/19/2020 12:46 PM, Carlos Trigo wrote: > Guys > > In my RV-10 both batteries (main Batt - Odissey PC-925, and Aux Batt - Odissey PC-680) are in the back, inside the tail cone, behind the baggage compartment. > This is a difficult place to reach, in the completed airplane, to connect the clamps of a battery charger/maintainer. > > Therefore I am going to install an external socket like this > > > in the airplane skin, to be easy to connect the charger from the outside. > > I am thinking in connecting both batteries to this socket through a SPDT switch, to be able to select which battery to be charged. > > Now the questions: > 1 - which is the current flowing through this socket when charging? > 2 - consequently, which gauge of wires should be used (#18)? > 3 - should I use any fuse in this circuit? If yes, which A? > 4 - is there any possibility to charge both batteries at the same time? If yes, which is the smart way to achieve that? > > Thanks in advance > Carlos > > Charge current will be determined by the state of discharge of the battery, and limited by the capacity of the charger. A depleted battery connected to a 12A charger could easily draw the entire 12A available from the charger. Hook it to a 50A charger and.... Wire gauge should be determined by the voltage drop and heat rise you're willing to tolerate, within the limits of the wire/insulation. I'd treat fusing the same way the alternator B lead is treated: size the wire for the max charger size, and fuse at the battery end to protect it from the battery. Don't forget the risk of someone attempting to jump-start the plane using that connector. Your call on how you avoid that risk. Switches/relays could connect both batteries for charging, but realistically, how often will you need to do that? A healthy SLA battery retains over 90% of its energy for many months without any charging whatsoever. You can learn a lot about (lack of) bench charging needs by reading Odyssey's technical docs. Charlie ________________________________ Message 3 _____________________________________ Time: 01:18:17 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: External socket to charge the airplane batteries At 12:46 PM 1/19/2020, you wrote: >Guys > >In my RV-10 both batteries (main Batt - Odissey PC-925, and Aux Batt >- Odissey PC-680) are in the back, inside the tail cone, behind the >baggage compartment. >This is a difficult place to reach, in the completed airplane, to >connect the clamps of a battery charger/maintainer. > >Therefore I am going to install an external socket like this >in the airplane skin, to be easy to connect the charger from the outside. That's an AC power connector . . . not polarized. No feature to prevent reversed connection. This is not a very environmentally robust device either. Is your airplane hangared? How about putting a goof-proof connector just inside the baggage compartment . . . leave door ajar and plug in shore-power. Connector stays out of weather. >I am thinking in connecting both batteries to this socket through a >SPDT switch, to be able to select which battery to be charged. What kind of charger? >Now the questions: > 1 - which is the current flowing through this socket when charging? Depends on charger. > 2 - consequently, which gauge of wires should be used (#18)? > 3 - should I use any fuse in this circuit? If yes, which A? > 4 - is there any possibility to charge both batteries at the same > time? If yes, which is the smart way to achieve that? The only time you need to CHARGE a battery is if you parked the airplane in a less-than- full state of charge. The only time you need to plug-in is if the airplane is going to be parked for an extended period of time. You don't need a switch, there's a way to wire a 3-terminal connector to effect battery paralleling for the purpose of MAINTAINING. But if you anticipate a need to CHARGE less than topped-off batteries, then we need to discuss the brand/model of charger. Have you published a power distribution diagram. How are these batteries wired and controlled? Bob . . . ________________________________ Message 4 _____________________________________ Time: 02:29:32 PM PST US From: Sebastien Subject: Re: AeroElectric-List: External socket to charge the airplane batteries Carlos I think your plan is way too complicated. My RV-10 has a fuse protected battery charging cord connected to each battery and going to the baggage compartment. If I want to charge that battery, I open the baggage door and plug into that battery. No external door, no switch. First select and purchase the charger. With many chargers you can disconnect the alligator clips and there is some sort of plug. Use the same plug on the end of the battery cable. My charger came with one free battery cable, the second one was $10. Many of these chargers use 2 prong automotive plugs which are cheap and available everywhere. On Sun, Jan 19, 2020 at 1:24 PM Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > At 12:46 PM 1/19/2020, you wrote: > > Guys > > In my RV-10 both batteries (main Batt - Odissey PC-925, and Aux Batt - > Odissey PC-680) are in the back, inside the tail cone, behind the baggage > compartment. > This is a difficult place to reach, in the completed airplane, to connect > the clamps of a battery charger/maintainer. > > Therefore I am going to install an external socket like this > > > in the airplane skin, to be easy to connect the charger from the outside. > > > That's an AC power connector . . . not polarized. > No feature to prevent reversed connection. > This is not a very environmentally robust > device either. > > Is your airplane hangared? How about putting > a goof-proof connector just inside the baggage > compartment . . . leave door ajar and plug in > shore-power. Connector stays out of weather. > > > I am thinking in connecting both batteries to this socket through a SPDT > switch, to be able to select which battery to be charged. > > > What kind of charger? > > > Now the questions: > 1 - which is the current flowing through this socket when charging? > > > Depends on charger. > > 2 - consequently, which gauge of wires should be used (#18)? > 3 - should I use any fuse in this circuit? If yes, which A? > 4 - is there any possibility to charge both batteries at the same time? > If yes, which is the smart way to achieve that? > > > The only time you need to CHARGE a battery > is if you parked the airplane in a less-than- > full state of charge. The only time you need > to plug-in is if the airplane is going to be > parked for an extended period of time. > > You don't need a switch, there's a way > to wire a 3-terminal connector to effect > battery paralleling for the purpose of > MAINTAINING. But if you anticipate a need > to CHARGE less than topped-off batteries, > then we need to discuss the brand/model > of charger. > > Have you published a power distribution > diagram. How are these batteries wired > and controlled? > > Bob . . . > ------------------------------------------------------------------------------------- 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.