Helpful Motor Tips


Tips and "How-To" From J&B Motor Sales! Battery Charging Guidelines EV or Motive Power Service Original equipment systems usually include an automatic charging system for battery charging. To maximize battery life and performance, batteries should be charged as outlined in the operating instructions included with the charging equipment. In the event of a charging-related battery performance problem, consult the OEM or Crown Battery service department to seek technical support. Extra care spent in proper charging will ensure battery performance. Battery charging equipment varies in terms or output and overall charging performance. For new or replacement chargers used in EV or motive power service, Crown Battery recommends electronically controlled automatic chargers that are programmed to deliver a high constant current rate of 12 to 18 amperes per 100 ampere-hours (20 Hour Rating) of battery capacity. The constant voltage phase begins after the gassing point is achieved (2.42 volts per cell). This stage of charge will last approximately 5 hours for a fully discharged battery. During the constant voltage phase the charger voltage is limited to the gassing level (2.42 volts per cell), and the input current is allowed to gradually diminish. When the input current falls to the finish rate setting of 3 to 4 amperes per 100 ampere-hours (20 Hour Rating) of battery capacity, the charge phase will change from constant voltage to constant current at 3 to 4 amperes per 100 ampere-hours (20 Hour Rating) of battery capacity – with a maximum charging voltage of 2.65 volts per cell. The charge will be terminated approximately 3.5 hours from the gassing point by an approved charge termination method such as DV/DT. Please note that fixed ferro-resonant chargers using this profile mush have finish voltages set at 2.58 volts per cell or higher. Batteries should always be recharged immediately following a complete discharge period. A weekly equalization charge – with the finish rate charge time extended 3 hours for a total of 6 hours from the gassing point – will ensure reliable discharge time and battery life. The charge factor of the standard recharge cycle should be equal to or greater than 1.08 (108%), while the charge factor of the equalization cycle should be equal to or greater than 1.15 (115%). To ensure optimum battery performance, total recharge time should in all cases be limited to 10 hours. Power off the charger before connection to the battery to avoid sparking. To avoid battery explosion, never charge a frozen battery – warming the battery to room temperature before charging service begins. Charging service should be terminated if batteries become excessively hot or if violent gassing or discharge of electrolyte occurs during charge.
When properly maintained and charged, Crown deep cycle batteries will provide many years of trouble-free service. However, failure to follow the operating and maintenance guidelines listed above may result in poor performance or premature failure. The following addresses some of the typical errors in operation and maintenance: Condition Check For • Undercharged Battery • Sulfated Battery • Cold Operating Environment • Poor Battery Performance (Less than 32°F/0°C Temp) • Defective Connector/Cable • Low Electrolyte • Old Batteries • Defective Charge Level Gauge • Unequal/Low Specific Gravities Over-filling • Undercharging • Overcharging • Excessive Water Service Container leak • Old Batteries • Odor During Charging Low Electrolyte • Overcharging • High Temperature Overcharging • Battery Overworked • Opportunity Charging
Troubleshooting Battery performance involves a three-point procedure: Visual Inspection: Check battery age or length of service if available. Inspect battery for damage - when physical damage to the battery container or terminals is present, replace the battery. If none, check the battery’s cell electrolyte levels. Fluid levels should be above the top of plates in all cells, and no higher than the top of the fluid level indicator: If the battery is sufficiently filled with electrolyte – proceed to step 2 If the top of the battery’s plates are not covered with liquid, add water, replace vent caps and place the battery on charge. Be sure no open flame or spark is near while the battery’s vent caps are removed from the battery. Specific Gravity Inspection: Hydrometer reading of all cells should be at least 1.235 and show less than 50 points difference between high and low. More than 50 points difference: replace the battery. Less than 50 points, but some cells read less than 1.235: recharge the battery. Replace the vent caps during recharge. Charge the battery using a properly matched automatic charger until all cells measure a specific gravity of 1.275 to 1.280. If charging won’t bring up specific gravity, replace the battery. The Power Behind Performance Open Circuit Voltage and Electrical Load Test: Battery open circuit voltage is an effective indication of battery state of charge. Determine the approximate state of charge from the following chart. Electrical load testing is an effective troubleshooting technique for identifying batteries with internal defects – but it is not an approved method for measuring deep cycle battery capacity. For this reason Crown Battery recognizes load test results as useful only for identifying batteries having bad cell conditions. Batteries with less than 75% state of charge should be charged before an electrical load test is applied to the battery. When load testing batteries, remove all battery cables, disconnecting the negative cables first. Make sure the battery terminals are free of corrosion and dirt. For batteries having stainless threaded stud terminals, attach a lead charging post to the threaded stud terminal before testing. Using a carbon pile load tester, apply a 50 to 75 ampere load for 15 seconds; remove the load. Refer to the chart at the left to determine the minimum passing voltage.