Seca 727 Series Service Manual page 6

Circuit description
Model 717,727,728,737,748,757 Blatt 4(3)
Diode 102 is used as polarity reversal protection
and overvoltage protection. Diodes 110 and 111
protect against discharge during battery operation
and against polarity reversal.
Electrolytic and tantalum capacitors are distributed
evenly over the printed circuit board as backup
capacitors for the operating voltage.
08.02.98 Law 25-01-02-467 Index E