Re: Dont change your bateries with the game on.



"kenny_ii" <kenny_iik@xxxxxxxxx> wrote in news:1176749894.483438.238150
@w1g2000hsg.googlegroups.com:

I looked at this game and figured out the MPU is the issue. Anytime
you work on a 'live' electrical circuit, you have a chance of causing
a problem. Changing batteries in an MPU while powered is NOT
guaranteed to be safe. Lots of arcing, ground path, static discharge,
signal shorting possiblities. I would say that in some situtations,
it's not going to be an issue, but do not blindly assume it's ok.

Of course if you behave like a dingus anything is possible. That's like
saying IF you strip an extension cord and shove it in the backbox,
anything could happen. But let's stick to likely scenarios here!

Ground path: Ummm, *no* difference between a machine on and off. The
ground plane is identical; the ground plane of the game (assuming the
ground plane is there) is hooked to the ground of the supply whether ON
or OFF.

Static discharge: again, *identical* risk whether the machine is on or
off. If you're charged and you futz around, you have the possibility of
blowing a chip if you don't take some grounding precautions.


Arcing:

The only arcing you're going to get off of a set of batteries (since
static discharge has already been addressed) is the potential across
those batteries. In other words, an arc "up to" 4.5V. Conveniently, the
circuit was designed to handle up to that amount, so it's not an issue.

It's not the same thing as when you have a faulty chip socket where you
could possibly have connections in one area and not a connection in
another area that would cause strange unintended circuit paths; this is
an *all-or-nothing* scenario, because the batteries are all in series
with each other.



Sorry man, I know you meant well but it's half baked voodoo mysterious
FUD like this that causes far more problems than it solves.

Far, FAR better to teach him how to ground himself properly. THAT will
keep him from torching stuff. Having the game off just makes it a pain
in the ass by wiping the audits and settings.

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