Car Chargers Keep Blowing Out

[[email protected]]

I got SIRIUS satellite car kit which plugs into the electrical outlets
in my Honda Accord (2004) and the first one died after less than a
week, then I exchanged it for a new charger and that one died in 5
minutes. I was then thrilled to find that a charger I have for another
device matches the specifications of the Sirius charger, so was using
that and now this morning that charger is dead. I'm starting to wonder
if maybe a power surge is causing this? Should I always unplug these
chargers when I turn off the car, and not plug them in again until the
car has been started? I took the one charger apart...can I repair it
by just replacing the little cylinder fuse inside? Are they easy to
find? Any help would be appreciated.

 

[Benjamin Todd]

I would say it's your sirius that has a problem...

 

[[email protected]]

Could you elaborate , please? Also, I should note that this has
happened with two Sirius radios (same model). When I first exchanged
the car charger I also was forced to exchange the radio (inventory /
return conditions).

 

[Benjamin Todd]

OK, I'll have a stab.
I think that the sirius probably has a surge current, or a strange effect
when it is first turned on...
If you're blowing chargers then i'm inclined to believe that it's not the
chargers that are incorrect, but that they're being overstressed when you
start the car. So either:

1. Siruis is drawing too much current on turn on
2. Car voltage supply is exceeding maximum input voltage for charger on turn
on

Would help to know what the sirius and charger make and numbers are and what
exactly the fuse protects.

If you say that the sirius is changed too, it could be a design flaw, or it
could be your Honda has a wobbly 12V when you turn it on. But i'd not think
that was a likely candidate.

Ben

 

[Chris]

I got SIRIUS satellite car kit which plugs into the electrical outlets
in my Honda Accord (2004) and the first one died after less than a
week, then I exchanged it for a new charger and that one died in 5
minutes. I was then thrilled to find that a charger I have for another
device matches the specifications of the Sirius charger, so was using
that and now this morning that charger is dead. I'm starting to wonder
if maybe a power surge is causing this? Should I always unplug these
chargers when I turn off the car, and not plug them in again until the
car has been started? I took the one charger apart...can I repair it
by just replacing the little cylinder fuse inside? Are they easy to
find? Any help would be appreciated.

Hi, Jeff. Mr. Todd has given good advice. But if you happen to have a
voltmeter, check something else, too. Turn on the engine, then with
all the accessories off, read the battery voltage. (Be careful to keep
the DVM leads away from the fan and moving parts). If you're reading
much over 14.2V, it's possible your Honda voltage regulator may have
gone south. The high voltage could be stressing your plug-in power
adaptor, causing it to fail.

Voltage regulator problems sometimes take a bit of time to kill the
battery, but especially if your car is starting sluggishly or you find
yourself needing a jump start, that's something else to look at.

You may also want to look inside the cigarette lighter socket for a
burned connection. If something pitted the pin contact in the middle
of the socket, that could cause an intermittent electrical contact
which could also kill the adapter. The socket is easy to replace (make
sure you diisconnect the car battery before attempting this).

After you've cleared these things up, you might want to go with an OEM
adapter from Sirius. They're not that much more expensive.

Good luck
Chris

 

[ehsjr]

I got SIRIUS satellite car kit which plugs into the electrical outlets
in my Honda Accord (2004) and the first one died after less than a
week, then I exchanged it for a new charger and that one died in 5
minutes. I was then thrilled to find that a charger I have for another
device matches the specifications of the Sirius charger, so was using
that and now this morning that charger is dead. I'm starting to wonder
if maybe a power surge is causing this? Should I always unplug these
chargers when I turn off the car, and not plug them in again until the
car has been started? I took the one charger apart...can I repair it
by just replacing the little cylinder fuse inside? Are they easy to
find? Any help would be appreciated.

It may be a spike that is causing the problem.
At a minimum, put a 1.5KE15A transorb across
(banded end to + ) the input to the charger.

Some people recommend using 2 transorbs - one
rated at 15 volts like the 1.5KE15A, and one
rated a lot higher, like the 27 volt 1.5KE27A,
both in parallel across the input.

Ed

 

[w_tom]

If a power surge caused your problem, as detailed in the other
newsgroup (alt.auto.honda?) where this same poblem was posted - how
great must 12 volts increase and not cause damage? Even 15 volts is
well below what any electronics must withstand without damage. Any
replied should have known that. Sirrius hardware design is a more
likely suspect - bad design.

I looked at what is being sold in Radio Shack. Now that Radio Shack
is more dominated by bean counters - which is why they are doing so
badly - not corporate management with technical background - now Radio
Shack starves us of basic facts. For example, what is the output
current for a Sirruis AC adapter? RS cannot be bothered to provide
useful information even on the box - a corporate bias that you are and
should remain technically naive.

So I look at the size of those adaptors. Only using ballpark
estminates and decades of experience, that 2 amp fuse may be too small
- a design error.

Now we discuss what all responders here should know. Does a 2 amp
fuse blow at 2.5 amps? Of course not. Fuses follow a well defined and
commonly known curve - I squared t - current squared times time. If a
power supply outputs 2 amps constant, then its fuse should be three or
four amps. Maybe larger is the load current varies significantly. 2
amp fuse may blow after maybe 24 hours of operation at 2 amps.

Let's say lower auto voltage during starting causes adaptor to draw
increased current. Then we demand a number. A 2 amp load might
increase to 2.3 or 2.5 amps for a short time (notice time is also a
necessary parameter). Fuse then can provide 2 amps for years should
then not blow at 3 amps for a short period - if properly sized when
designed AND confirmed by top management in the design review.

In short, I suspect design used a fuse too small. But again, since
Radio Shack now shows contempt for the technically literate, then they
don't put any numbers on those many Sirrius adaptors. No numbers on
that AC adapter suggests the AC adaptor would not be UL approved -
another indication of inferior design.

No way a power outlet has any relationship to a fuse that blows
inside the Sirrius adaptor. Another suggested a weak Honda outlet
caused lower voltage and therefore increased current. Good until we
apply numbers and the I squared T relationship - how fuses are sized.
With numbers, then a subjective idea has no merit.

Due to a disrespect for the more technically informed (by Radio
Shack), then your responses are speculation. However some speculation
is based in science. Other speculation - such as the Honda createing a
surge too large - is total bullshit.

Try a 3 amp fast blo type fuse - 32 or 250 volts. Also posted
elsewhere was as kludge solution involving automatically resetting
fuses. I am surprised you did not ask for details - instead jump on
nonsense ideas such as surges. However the automatically resetable
fuse may be slightly too large.