Alpha Technologies Industrial Ni-Cd Batteries Standard Range - Manual (Page 27)

EN-ALPHA-TMSR-001 (10/09) 27
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7.4. Charging in operation
7.4.1 Continuous battery power supply
(with occasional battery discharge) Recommended charging voltage for ambient temperatures
+ 20°C to + 25°C Do not remove the vent caps during fl oat-, boost charge and buffer operation. The
current limit should be 0.3 ItA maximum in general.
7.4.1.2 Two level charge
Floating 1.40 - 1.42 V/cell
Boost charge: 1.55 - 1.70 V/cell
A high voltage will increase the speed and effi ciency of recharging the battery.
7.4.1.3 Single level charge
1.45 - 1.50 V/cell
7.4.2 Buffer operation
Where the load exceeds the charger rating. 1.45 - 1.55 V/cell
7.5. Periodic Maintenance
The battery must be kept clean using only water. Do not use a wire brush or solvents of any kind. Vent caps can
be rinsed in clean warm water if necessary but must be dried before using them again. Check regularly (approx.
every 6 months) that all connectors, nuts and screws are tightly fastened. Defective vent caps and seals should
be replaced. All metal parts of the battery should be corrosion-protected by coating with a thin layer of anti-
corrosion grease. Do not coat any plastic part of the battery, for example cell cases! Check the charging voltage. If
a battery is connected in parallel it is important that the recommended charging voltage remains unchanged. The
charging current in the strings should also be checked to ensure it is equal. These checks have to be carried out
once a year. High water consumption of the battery is usually caused by improper voltage setting of the charger.
7.5.1 Equalizing charge
It is recommended to carry out an equalizing charge once a year to maintain capacity and to stabilize the
voltage levels of the cells. The equalizing charge can be carried out for 15 hours at 0.2 ItA or with the boost
charging stage in conformity with the characteristic curve of the available charging implement. The electrolyte
level is to check after an equalizing charge. In order to equalize the fl oating derating effect it is recommended
to charge the battery once a year for 15 hours at the rated charging current 0.2 ItA. Then discharge the
battery down to 1.0 V/cell and charge again for 8 hours at the rated charging current 0.2 It A.
7.0 Installation and Operation, continued