The monitoring of vital operating parameters of lead acid batteries has made significant advances with new electronics and the price reduction of such devices. Watch for the coming IEC guideline (1997) for stationary lead acid battery monitoring.

The use of a monitor has to be decided case by case.

Accu Oerlikon suggests to monitor the battery performance according to the details of the Compact-Power operating instructions. For an adequate surveillance monitor and record at least

• cell and monobloc voltages and battery and temperature once every 6 months. Adjust, if necessary the battery float voltage.

• battery capacity with partial or complete test discharges every year or according to local standards.

The monitoring of the internal resistance or conductance of cells and monoblocs with a commercial conductance meter (Hewlett Packard, Hioki, Midtronics, Albèr, and similiar) can provide a quick qualitative view of the battery capacity instead of a more complex to organize capacity test. However the correlation conductance vs. capacity is not yet as firm so to supplant the capacity test completely (see INTELEC 1993-94-95 Conference Proceedings).