Had a look through my booklet, and found this;
Tests the battery for possible deep discharge or sulphation. If necessary, the OptiMate IIISP automatically engages a special high voltage recovery mode (maximum 22V) with controlled very low fixed current, so as to desulphate very flat batteries, for up to 2 hours, controlled by an internal timer.
Sound like you batteries flat as a pan cake...
19-Mar-2006, 21:22 
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