Lead Acid Battery Operating Instructions - Alcad.com

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7 Charging When all the cells have been placed on the rack, fasten the intercell and intertier connectors in place using the bolts, nuts and washers supplied,taking care to maintain the positive-to-negative series connection sequence.. Apply an even coating of "No-Ox-ld" grease to all hardware before and after assembly. Use the insulated wrenches supplied to tighten the parts firmly together. Care must be taken to avoid short circuiting the cells with any of the battery hardware. The recommended torque values for the connector bolts are as follows: PMF, SGL Types 50 inch pounds SD, SDH 70 inch pounds SGH 105 inch pounds Make sure that the positive terminal of one cell is connected to the negative terminal of the next throughout the battery, leaving the main positive and negative terminals of the battery free for connection to the charging source. Take particular care to check the positive to negative sequence for flexible intertier or interstep connectors between rows of cells. Connect the positive terminal of the battery to the positive terminal of the charger and the battery negative to the charger negative. Affix the cell number labels to the cell jars and covers making sure that the surfaces are dry and clean. It is usual to number the cells beginning with # I at the positive end of the battery, numbering consecutively in the same order as the cells are connected electrically, through to the negative end of the battery. 7.1 Initial Charge (Dry-Charged Cells) An initial charge must be given to all batteries which have been filled on site (see Section 4). (Those batteries which have been shipped filled and charged should be given a freshening charge before being put into service (see Section 7.2)). The preferred method, using a constant voltage charger, is to charge the cells at a constant potential of 2.70 volts per cell. After the cells have started to gas, the charge current should not be allowed to exceed the finishing rate shown in Section 11. Monitor the cell temperatures carefully and discontinue the charge if they exceed 110.F (43.C). Allow to stand on open circuit until the temperature falls to 100.F (38¨C), at which point the charging process may be resumed. The duration of the initial charge under the above conditions will be approximately 24 hours. It is possible to use a lower charge voltage (down lo a minimum of 2.33 volts per cell), but this will extend the duration of the initial charge to as much as 100 hours or more. The initial charge may be terminated when the specific gravity readings of all cells have remained constant for at least 2 hours. 7.2 Freshening Charge It is normal for lead acid cells to lose charge while in transit or during storage. For this reason, a freshening charge should be given before putting the battery into service. This is normally accomplished using the "equalize" voltage setting on the charger (see Section 7.3). -5-
The duration of the freshening charge is dependent on the amount of charge to be restored, the temperature, and the charge voltage utilized. In general, it should not be necessary to charge for more than 96 hours. The freshening charge should be continued until the specific gravity readings for all cells have remained constant for at least 2 hours. 7.3 Charging In Service Most standby power batteries are charged by "float" or modified constant voltage chargers. The information in these instructions is based on this charging method. Details of battery operation from other charging sources may be obtained from Alcad Standby Batteries. Floating battery systems are those where the charger, the battery and the load are connected in parallel. The charger output voltage is set to a particular value and under normal conditions the applied charging voltage is maintained within very close limits. Most float chargers have two adjustable charge voltages: the "equalize" setting (also known as "boost", "high rate" or "recharge") will restore the battery to a fully charged state within a relatively short period; the "float" setting will maintain the battery in a high state of charge with minimal water consumption. The float voltage may be set between 2.15 and 2.25 volts per cell. The recommended set- is 2.23 volts per cell, which will maintain the battery in a fully charged state without the need for periodic equalize charges. Float voltages above 2.23 volts per cell should be avoided if the operating temperature frequently exceeds 80°F (27°C). For float voltages below 2.23 volts per cell, periodic equalize charges should be given in accordance with the following table: Float Voltage (per cell) 2.23 Never -6- Equalizing Required at these Intervals 2.20 Every 6 Months 2.17 Every 3 Months 2.15 Every Month Equalizing is generally required when the total voltage spread between the cells is greater than 0.04 V under float charging conditions. Charging at the equalize setting is necessary for fast recharging after an emergency discharge. A short equalize charge is also desirable after addition of distilled water to assist in mixing the acid and water (see Section 9.3). Equalizing may be carried out at voltage settings above 2.30 volts per cell. The maximum equalize voltage is generally determined by the maximum voltage which the system can tolerate. Normal values of equalize voltage are around 2.33-2.35 volts per cell. The battery should not be subjected to a final charge current, during the gassing state, of greater than the finishing rate shown in Section 11. This current corresponds to a charge voltage of approximately 2.7 volts per cell. The length of equalize charging required will depend on the depth of discharge, electrolyte temperature and normal float voltage level. The best guideline is to continue equalizing until the specific gravity of the acid in the pilot cell (see Section 9.4) has been constant for at least 2 hours.
Page 1: Lead Acid Battery Operating Instruc
Page 4 and 5: 1 Safety Precautions 1.1 Read Befor
Page 6 and 7: 4.2 Filling the Cells When mixing b
Page 10 and 11: 8 Specific Gravity Readings 9 Batte
Page 12 and 13: 11 Cell Data 1 1.1 Planté A sample
Page 14 and 15: 11.3 Tubular Plate Monoblocs Finish

Lead Acid Battery Operating Instructions - Alcad.com

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