Electrical Checks on Vehicle

It is strictly required to measure surface voltage of the battery before mounting it to the vehicle. Acceptance criteria of the battery should be in minimum 12.6 volt. If battery voltage is 12,4 or below, this battery is not suitable for use. The reason is that sulphation reaction has started in this battery. Accuracy rate of battery is 75% and below. In such case, if battery is mounted to the vehicle, life of battery will reduce considerably.

For mounting of battery, positive and negative cable should be connected respectively while connecting the battery. In computerized vehicles, system should be fed with service battery to maintain electric power. After mounting of battery, fixed electrical consumption value in the system should be measured.

For measurement of fixed electrical consumption measurement, inductive pickups with 10 mA of sensitivity should be used. It is required to connect inductive pickup to the negative cable and measure the value. Values should be 20 to 30 mA in 12-volt systems and 60 to 80 mA in 24-volt systems. If measured value is much higher than expected value, standard consumption of vehicle is high or electrical consumption of vehicle is out of standards.

For example, fixed electrical consumption value in automobiles is 100 mA. It means 100 mA of energy will be supplied from this battery per hour. If the vehicle is left in park position for 24 hours, battery will be exposed to 2400 mA or 2.4 ampere-hour of discharge in total. If this vehicle is left in park position for one week, battery of the vehicle will be exposed to 16.8 ampere-hour of discharge. Loss in battery may be calculated by dividing rate of discharge for related time by ampere hour of the battery.

If a vehicle that uses 60 ampere-hour battery is left in park position, this battery will be discharged at 28%. In order to prevent such situations, fixed consumption of vehicle should be measured during maintenance and controls of battery and necessary measures should be taken in inappropriate conditions. Following electrical consumption measurement, the second is measurement of charging system. For this process, vehicle should be started. When idling speed is 2000 cycle/minute and consumption is open, voltage value of battery should be measured. If voltage value is between 13,8 and 14,4 at each three steps, it means charging system (Alternator) is in proper condition. However; if voltage value is out of these values, it is required to check the charging system. All these electrical system measurements should be made with a new and full battery. If battery is in discharge position, measured values will vary. In such case, there may be mistakes in determinations.