[COLVERT]

Originally Posted by MarkS

If unconnected to a battery, the solar panel gives out between 0V (in darkness) and 18-22V in bright sunlight.

There is no reason that the voltage should pulse.

When connected to a battery, the 18-22 V in bright sunlight is 'clipped' by the battery to be between 12-13.8V, this keeps the charging voltage within acceptable limits.

WARNING: If you have a solar charger connected VIA THE CIGAR LIGHTER SOCKET, and you disconnect the battery (or any relevant fuse), this charging voltage is no longer 'clipped' by the battery, and MAY potentially rise to above 15V, (to 22V), 'potentially' damaging vehicle electronics.

So if you intend to disconnect the battery, or unplug fuses, it is a wise precaution to disconnect the solar charger from the cigar lighter socket FIRST.

FWIW, most solar chargers, when used in the latitudes of the UK, seem to give out approximately 1/2 the rated power, not what the manufactures may claim.

A 4W panel, giving 190mA for 6-8 hours, equates to 1.5Ah

Clipped ???---I guess---Absorbed by the battery would be better understood by the non technical folk.--