You will need
- Maintenance-free Varta battery, charger.
Check the status of the rechargeable maintenance-free battery Varta. Usually, with most maintenance free batteries measure the electrolyte density in each cell is impossible. So measure the voltage using a voltmeter, or determine the degree of charge of the built-in color indicator that such devices located on the top wall of the housing.
A fully charged battery has a green light. As discharge the color darkens to black. The latter indicates the need for charging. If the indicator light yellow means an unacceptably reduced level of the electrolyte. Or add distilled water or change the battery. To charge the battery in this state and to light it from another device, impossible.
Turn on the car all the appliances that consume energy. Measure the voltage at the battery terminals with a voltmeter. If the voltage is less than 12.2 V, the battery is dead; if from 12.2 to 12.4 In part.
To charge the battery, remove it from the vehicle.
Charge maintenance-free battery at a constant current equal to 1/10 of the battery capacity. 2 hours after the voltage on the battery will cease to change, stop charging, or charge the battery current of 1.5 A. It is safer, however, requires more time to restore its properties.
Don't forget that too fast charging high current leads to overheating, harm the battery plates. Make sure that the electrolyte is not boiled. Disconnect the charger, cool the liquid and charge again.
If the battery voltage is below 12.2 V - it is completely empty. In this case, seek help in a specialized center. The charging process should be under the constant supervision of a specialist. Besides it is long lasting – up to three days.
Some modern vehicles when removing the battery to lose the settings of the electronics. In this case, maintenance-free batteries charge without removing the battery from the machine. Do it in a dry and warm room. The battery should be at room temperature.
Turn off or put in sleep mode all electrical appliances and lighting. Caution: do not close the hood not to close the terminals. First connect the charger to a battery when the current is turned down. Then connect the charger to the network. The current strength gradually increase, to avoid dangerous power surges.