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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default Solar Panel Help

"BF Lake" wrote in
news:JPbkh.99541$hn.5563@edtnps82:

Don't follow. (also haven't seen previous part of this) ISTR the
purpose of the blocking diode is to prevent the battery from charging
the solar panel at night.



Stops the battery from reverse current through the solar panel when solar
panel voltage is lower, not just at night. This causes damage to the
panel's silicon junctions and reduces its life by causing migration of the
doping across the junction.

Never use a solar panel to charge a battery unless there is, at minimum, a
blocking diode to prevent reverse current.

Larry

Kitchen theories about it reducing solar panel output are nonsense. Solar
panel open circuit voltages are above 18V in bright sunlight. Six tenths
of a volt the diode drops means nothing. The panels are DESIGNED with
blocking diodes in mind.....