Last year the voltage regulator on the alternator died, apparently
causing a voltage spike. Fried two new batteries and my instrument
cluster, radio survived. My usual practice was to charge both batteries
at the same time when engine is running. When under sail run the
electronics off one battery, odd (Batt 1) or even (Batt 2) depending on
the date. Now charge only one battery at a time, depending on which I
was using for house/electronics. Still powered by an Atomic 4.
Don Kern
Fireball, C&C35 MkII
Bristol, RI
On 9/27/2019 3:08 AM, Matti Airas via CnC-List wrote:
Hi,
I'd check the battery and alternator connections carefully. And the
main switches, too. If the batteries get disconnected while the motor
is on, the alternator will create a load dump that can be even over
100V for a fraction of a second. In principle, automotive and marine
electronics should be protected from that but you never know. I'm only
speculating, but if that was the reason, maybe the voltage spike was
short enough that the fuses didn't have time to heat up?
Google for "load dump" if you want to learn more.
Cheers,
Matti Airas
C&C 36 "Hurma"
Helsinki, Finland
On Thu, 26 Sep 2019 at 22:26, Ian Matthew via CnC-List
<cnc-list@cnc-list.com <mailto:cnc-list@cnc-list.com>> wrote:
I have been following the list for many years and I enjoy reading
the wisdom of this group. I have an interesting problem and seek
your advice.
I have an very intermittent electrical problem (in fact it has
only happened twice in the last 7 years. In both cases it has
resulted in electrical / electronic components becoming 'blown
out' with all fuses inline remaining good.
The first time I suddenly lost my AM/FM radio and ALL my
navigation lights. The engine also stopped as I had no power to
drive the electric fuel pump. This happened when motoring back
home at night after a long race. Fortunately there was wind and a
hand-held VHF and a powerful spotlight on the sails allowed us to
be seen by commercial traffic. Afterwards, I checked - ALL the
incandescent bulbs that were on had blown, but the fuses were OK.
The radio had internal circuit board components blown but again
the inline fuses (there are 2) were OK. In the case of the fuel
pump, this had to be replaced.
Thinking this may have been a spike from the alternator, I
replaced the alternator.
Last week (3 years later), motoring back in the dark I had a
similar problem, but this time only my VHF radio 'blew'. Again
the inline fuse was good. The navigation lights have been
replaced with LED lights and the AM/FM radio was off.
I often motor after long races and this has only happened twice!
Does anyone have any ideas as to what may have caused this. I am
an engineer so can diagnose most things but this has baffled me.
I am about to upgrade my VHF radio for one with DSC and internal
GPS and to add some wind instruments. (I have a Raymarine
knotmeter/depth meter combined, and a EV-100 autopilot.) I want
to separate my electronics electrical input and have considered
putting them on an isolated battery, but charging is a problem.
Is there some circuit protector I can put in place to stop this
happening again?
All suggestions welcomed.
BTW - for those of you with 29 mk 1's - you can race them
competitively in strong winds (as is usual on San Francisco Bay) -
keep the boat flat and have a really good crew!
--
Ian Matthew
"Siento el Viento" C&C 29-1
San Francisco Bay
_______________________________________________
Thanks everyone for supporting this list with your contributions.
Each and every one is greatly appreciated. If you want to support
the list - use PayPal to send contribution --
https://www.paypal.me/stumurray
_______________________________________________
Thanks everyone for supporting this list with your contributions. Each and
every one is greatly appreciated. If you want to support the list - use PayPal
to send contribution -- https://www.paypal.me/stumurray
_______________________________________________
Thanks everyone for supporting this list with your contributions. Each and
every one is greatly appreciated. If you want to support the list - use PayPal
to send contribution -- https://www.paypal.me/stumurray
