The method is:
Use the charger to charge the car battery, first look at the number of car battery volts, is a battery, the charging voltage is adjusted to 12V, two on the 24v. Then see which is the positive electrode of the battery (generally the positive electrode to the motor, the negative electrode to the iron), use the red clip of the charger to clamp the positive electrode, black clamp the negative electrode, plug in the power line can be charged. At this time, two meters of current and voltage on the charging machine are raised