Thanks, Colin.

And, like you, I welcome any further thoughts anyone has on the question.

By the way, I appreciate everyone taking my question for what it was. ... A
sincere question from someone who is always willing to learn, and to admit
what I may not know.

This is one of the things that continues to make this list so great.

Tom Behler: KB8TYJ


-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Colin McDonald
Sent: Friday, October 24, 2014 5:03 PM
To: [log in to unmask]
Subject: Re: Best procedure for connecting and disconnecting a 12-volt
battery

Tom:
in a typical 12VDC system, it actually doesn't matter much which way you
disconnect, or reconnect the battery terminals.
You may get less sparking by connecting the ground first when reconnecting
the terminals, but you will still get a bit of sparking either way when
reconnecting.
I say it doesn't matter much because from both personal experience, and from
knowing and learning from various auto mechanics over my life time, that the
ground last, ground first concept when disconnecting and reconnecting
battery terminals in a 12volt auto system is a standard way to do it, but
that it doesn't make any electrical difference to anything on the system if
you do it the other way.
Remember, once one side of that circuit is broken, it doesn't matter what is
still connected, the circuit is broken and there is no longer a posative or
negative path in the circuit.
So, you and your YL were both right at the end of the day.
Now, if anyone has any theoretical info on which is the better way to do
this, chime in...acording to a good friend who has been a mechanic for 40
years and who holds four red seal tickets the order in which you connect or
disconnect a vehicle battery is not important.

73
Colin, V A6BKX
--------------------------------------------------
From: "Tom Behler" <[log in to unmask]>
Sent: Friday, October 24, 2014 2:37 PM
To: <[log in to unmask]>
Subject: Best procedure for connecting and disconnecting a 12-volt battery

> Hi, all.
>
>
>
> I am sure that, to some, this question might seem to be very 
> elementary, especially for someone like me who holds an Extra class 
> license.  So, please bare with me, and understand why I am asking the 
> question.  As a college professor, I always try to teach my students 
> not to simply memorize procedures or concepts just for the sake of 
> doing so.  I tell them that real learning involves understanding the 
> procedures and/or concepts and the reasons behind them.  I also stress 
> that true learning involves being able to apply what you have learned 
> to real life situations.
>
>
>
> Anyway, here's my question:
>
>
>
> Earlier this afternoon, my XYL and I were in the process of getting 
> our summer camping trailer winterized for the season, and taken to a 
> local facility for winter storage.  As we worked, it came time to 
> disconnect the house battery from the unit, so that it can be put on a 
> trickle charger during the winter months.
>
>
>
> Before we disconnected the battery, we were discussing the best and/or 
> safest procedure for doing so.  We never worried about this with the 
> drivable RV we used to have, because it was always kept in our 
> driveway and plugged into our main house power all winter.
>
>
>
> Anyway, my proposed approach was this:
>
>
>
> When disconnecting the battery, disconnect the positive side first, 
> and then the negative.  The idea here is that you always have the 
> negative or ground connected when you're working with the battery.
>
>
>
> When re-connecting the battery, I proposed connecting the ground 
> terminal first, once again, to give you a ground to start from, and 
> then connect the positive terminal last.
>
>
>
> My XYL's approach was the opposite:
>
>
>
> She argued that when disconnecting the battery, disconnect the 
> negative terminal first, and then the positive.  . When connecting, 
> connect the positive first, and then the negative.
>
>
>
> As a smart person who has much faith in my XYL's judgment, I decided 
> to go along with her proposed approach, and happily, we are both still 
> here to talk about it.
>
>
>
> However, I know that I have connected and disconnected many a battery 
> using my initial approach, and I've survived that as well.  Perhaps I 
> just got lucky, but I always thought I was proceeding with care, and 
> with the correct procedure.
>
>
>
> Once again, I hope nobody minds this question, but I consider everyone 
> here to be knowledgeable on many things, and I trust that you will all 
> be able to go with the idea that the only stupid question is a 
> question that goes un-asked.
>
>
>
> Your wisdom on the topic would be most appreciated.
>
>
>
> Thanks for listening.
>
>
>
> Tom Behler: KB8TYJ
>
>
>
>
>
>