BatteryMinder ring terminal connection

Jdm

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Jdm
Have any of you mechanic types fabricated/installed a ring terminal battery charger connection on your certified aircraft? AudioAuthority has an approved kit (BM-AIK2A) but quality is questionable according to feedback. Especially with the glass fuse situation- those things can get hot, and are problematic anyway.
I prefer the BatteryMinder version. They offer two basic ring terminal kits (RTA-2415 and RTA-2415EXP) but they are not listed as approved for certified aircraft. I know of certified aircraft flying around with these installed however, and they are actually signed off by a licensed mechanic.

Confusing! How is everyone working around this?

Appreciate it.
 
I put a ‘pigtail’ on, it came with my tender. I don’t remember much fuss from my mechanic. If so, take it off before annuals.

I only use the tender periodically, up to a ‘green light’, not plugged in indefinitely.
 
IA is not required. I want to know how a licensed mechanic handles this situation?
 
Especially with the glass fuse situation- those things can get hot, and are problematic anyway.

would you mind expounding on this? Did they have a mfgr'ing Q.C. Issue? Generally, fuses are (almost) always both safer and more precise than circuit breakers are.
 
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No, I’m not looking for any circuit breakers! I need an in-line fuse, but I want the type that’s best for my application. The batteryminder (unapproved) versions come with a nice plug type fuse holder that is durable and sealed against moisture.
The AA version is undesirable for a few reasons.. It uses an old style, glass fuse holder that is not moisture resistant. They are very prone to corrosion in the engine area. I don’t know about any QC issues, but there have been reports of them overheating. This was mostly due to people leaving the battery master on while in use. The plug type fuse holders have had no issues with that. On top of that, the AA version is also extremely over priced for common wiring and terminals.
 
fabricated/installed a ring terminal battery charger connection on your certified aircraft?
Have fab/installed a number of them. It's a minor alteration (AP logbook sign-off) as long as you keep it simple and don't start cutting holes in cowling or structural panels which can change the classification.
they are not listed as approved for certified aircraft.
FYI: for a vendor to produce/sell parts that "may" be installed on a TC'd aircraft the parts must have some sort of Part 21 approval. For items used in an alteration under Part 43 there is a different set of rules to follow. So while BatteryMinder sells the kits, they leave it up to the installer to determine whether it can be installed or not. A number of vendors offer parts in this manner.
 
I installed the Audio Authority one about 6-7 years ago. No problems until a few weeks ago - the positive connection to the charging plug broke. I re-soldered it, and we are back in business...
 
Have fab/installed a number of them. It's a minor alteration (AP logbook sign-off) as long as you keep it simple and don't start cutting holes in cowling or structural panels which can change the classification.

Excellent info, and exactly what I was thinking. Did you actually fabricate something simple? I haven’t had any luck finding an approved inline fuse holder of the plug/sealed type.

So while BatteryMinder sells the kits, they leave it up to the installer to determine whether it can be installed or not. A number of vendors offer parts in this manner.

Another excellent point. How would you reference/justify something like this if you felt that it were indeed an adequate/airworthy installation? I don’t think AC43.13/1B address this exactly. I’m going to have another look at my copy. It’s been a while since I cracked it open:)
 
When it’s clearly written that it’s not approved for certified aircraft??

the manufacture can write what ever they want in there ad copy and manuals. just as there is no such thing as an "experimental: radio, but they sure love to market them that way. it is up to the installing A&P to determine if the installation is legal for installation in an aircraft. if the A&P decides that the part is legal to install, and the installation is done in accordance with acceptable data or approved data (determined by if it is a major or minor alteration) then it is good to go. since that would be a minor alteration, installing it in accordance with AC43.13 is acceptable data, and a log book entry is made then its good to go.
 
approved inline fuse holder
Falls under Standard parts. Same as would the connectors you use. There's a number of guidance docs on what are Standard parts. Regardless, as I mentioned, the mechanic determines what is acceptable for the install under Part 43.13 not the vendor. Any of the fuse holders at Aircraft Spruce will work and would be considered acceptable. Most of the battery chargers I made the battery pig-tail for had built in fuses in the charger.
How would you reference/justify something like this if you felt that it were indeed an adequate/airworthy installation?
That's what the A&P certificate is for. Not every install/alteration has a specific reference. So you look for multiple references that cover the alteration like a wire reference, connector reference, routing reference, etc. all of which are in AC43-13-1B. Then you perform the work and sign it off as general or specific as you want.
 
it is up to the installing A&P to determine if the installation is legal for installation in an aircraft.

Ok, great points in whole your post. I appreciate it. I’m just having trouble finding any documentable source to help make this determination. I get the actual installation part IAW standard practices AC43-13. It’s the determination of airworthiness that I seem to be struggling with. An IA friend told me that it’s generally not a big deal and that he actually found a FAA source once that addressed this, but he couldn’t remember the document off hand.
 
It’s the determination of airworthiness that I seem to be struggling with
Curious. What specific airworthiness document/reference would assist you in your determination of airworthiness for installing wires and connectors on an aircraft?
 
Curious. What specific airworthiness document/reference would assist you in your determination of airworthiness for installing wires and connectors on an aircraft?

I’m curious about that also. It had something to do with the fact that it’s simple wiring connection that must be disconnected (inactive) and plugged when it’s not in use. He said that if the battery charger were to remain connected to the ring terminal kit, and in a baggage compartment for instance, it would not be in compliance. He’s a sharp guy, I’m sure he found an obscure reference someplace. If he gets back with me I’ll be sure to share the info.
 
I personally really like the Anderson connector setup. It's easy to connect with one hand and has a good positive "snap" as it's connected and has a nice dust cover to go over it when not in use. Plus you can hard mount it in a convenient location as opposed to just zip tying the standard floppy connector somewhere. I guess don't understand the concern over the fuse holder/glass fuse.
 
I’m curious about that also....He said that if the battery charger were to remain connected to the ring terminal kit,
It was my understanding you were struggling to sign-off the install, not someone else? Regardless, leaving the charger connected to the battery pig-tail (as you state above) and flying is something entirely different. FYI: there are a number of alterations and mx actions that result in leaving disconnected, stowed wires and parts in aircraft. All of which fall under a simple logbook sign-off by an AP. So if you're looking for a specific FAA reference that allows you to install a charging pig-tail on an aircraft battery and leave it installed for flight, well I can't help you there as I've never seen one nor needed one. Best of luck.
 
I personally really like the Anderson connector setup

Yeah I definitely like the looks of the Anderson. Never used one but people seem to prefer them.
 
It was my understanding you were struggling to sign-off the install, not someone else?

You’re understanding was correct
 
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FYI: for a vendor to produce/sell parts that "may" be installed on a TC'd aircraft the parts must have some sort of Part 21 approval. For items used in an alteration under Part 43 there is a different set of rules to follow. So while BatteryMinder sells the kits, they leave it up to the installer to determine whether it can be installed or not. A number of vendors offer parts in this manner.

Ok, please keep in mind that other than a couple of years of part 91 mx work right right out of A&P school (1987), my A&P background has primarily been as a 121 mechanic for various majors. We generally had a hard reference for most everything. I do have an IA friend that I pay to look over any large work. He signs behind me on my annuals etc. I appreciate having him as an extra set of eyes once a year or so. He totally agrees that this is a minor situation, so I’m fine in that regard.
I also see now that it’s clearly up to the A&P in this situation. It does seem hard to make determinations like this at times. Obviously, if I were to get a super cheapo disconnect kit from harbor freight and install it on a certified aircraft, it would be poor judgment on my part. So how do you guys draw that line? I’ve been an A&P long enough to spot quality alright, but prepackaged, non-certified kits like this are hard to evaluate quality. I’m sure if the hangar burns down due to poor wiring parts it would be the insurance lawyers that would have the last laugh.
I have no doubt that the non-certified battery minder ring kit is just as good as any certified option. Actually, I have good reason to believe it’s better than the certified option! I just want to exercise my A&P authority properly for personal and liability reasons, which is exactly why this little stuff bugs me so much.
 
It was my understanding you were struggling to sign-off the install, not someone else? Regardless, leaving the charger connected to the battery pig-tail (as you state above) and flying is something entirely different.
You're not going to make it too far before you run out of extension cord.
 
So how do you guys draw that line?
In general, there's two basic rules that will guide you: FAR Part 43.13(a) and (b). If the maintenance you perform falls within these guidelines then the rest will take care of itself. If what you want to perform is outside these guidelines then change/alter whatever is lacking to bring it back into this guidance. It is extremely rare when that can not be done. Looking to your ring kit, if you believe the quality of the wiring, etc. does not meet the required 43 performance requirements then change the wire, etc. with items that will meet those requirements. As an example, when a permanent charging pigtail is needed, I prefer to fabricate one using guidance found in AC 43.13-1B rather than purchase one for various reasons. So while you personally have to "draw that line" there are still plenty of references that can help guide you.
as a 121 mechanic for various majors. We generally had a hard reference for most everything.
FWIW: Part 121 mx, and by extension Part 135 ten pax or more mx, are on their own level as they can internally create and "approve" specific references and procedures--hence the reason those type ops have so many mx references. Part 91 mx, and by extension Part 135 nine pax or less mx, can not create their own references per se and are basically stuck following FAA references and by extension OEM references which include OEM main and supporting documents (airframe, engine, prop, appliance), FAA ACs, FAA Orders, FAA Handbooks, etc.
 
You're not going to make it too far before you run out of extension cord.
Ha. While I have seen aircraft try and leave still connected to a GPU... it has been known for people to leave their battery chargers in the aircraft, but minus the extension cord. Unfortunately, in one case an individual forgot to disconnect the charger and let all the smoke out of it once the alternator kicked in. ;)
 
I hooked the world's cheapest motorcycle battery minder to the battery. There's a part on the battery that plugs into the part that plugs into the socket. I think I installed that battery in 2016. I used the same setup in my Cherokee for years. I think the battery was 7 years old when I traded for the Mooney.
 
it has been known for people to leave their battery chargers in the aircraft, but minus the extension cord.

Exactly, that’s the situation my IA buddy warned about. Some people tend to leave the charger connected to the pig tail while flying.

when a permanent charging pigtail is needed, I prefer to fabricate one using guidance found in AC 43.13-1B rather than purchase one for various reasons.

I think I prefer to do the same, but as I mentioned previously, I’ve haven’t been able to find a good weather proof in-line fuse holder of aircraft quality. If it were located inside the airplane it wouldn’t be a big deal, but with the cessna it’ll be forward of the firewall. Also, the small SAE connector might actually work better for my 172 application, even though the larger Anderson connector is probably the best available.

I really appreciate all the feedback.
 
find a good weather proof in-line fuse holder of aircraft quality
FYI: A number of marine/industrial type electrical parts (connectors, fuses, etc.) fall under the definition of FAA Standard Parts. But even forward of the firewall there still is protection from the elements so going waterproof may not be an issue.
 
The BatteryMinder , small generic version, I purchased had its own 3 amp fuse built in to the pigtail that attaches to the battery. The more expensive version designed for my Concorde battery is heavier duty with a 8 amp fuse.
 
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