Using Analog and Digital Multimeters to Test Automotive Systems
The most commonly used automotive electrical maintenance tool may be a multimeter. A typical multimeter can test voltage, current, and resistance. Specially developed multimeters such as Fluke's F78/F88/F98 have many functions specifically designed for automotive testing, such as frequency, duty cycle, diode testing, temperature, lockout time (Dwell), and even engine speed (using accessories).
This information is about how to use Fluke's high-quality specialized multimeters and their accessories for car maintenance. The analog/digital combination method of this watch has completely different advantages from other watches, and its accessories make maintenance more convenient and easy. Although multimeters have been used for repairing cars for many years, most of them do not have specialized functions for car repair. Nowadays, computers and various sensors are widely used in cars, and a truly multifunctional multimeter is needed for car maintenance. The input impedance of early analog (pointer) multimeters was too low, which had a significant impact on electronic circuits during measurement. This type of meter mostly uses 9V voltage to test resistance, so it is easy to damage sensitive electronic components. In recent years, new digital multimeters (DMMs) have been widely adopted.
Its input impedance is high, and its accuracy and performance are superior to analog meters. The voltage during resistance measurement is also low (usually 5V, Fluke is 3.5V), so it will not damage the components of each sensor. But there is also a problem with the digital table. It cannot display information on the increase or decrease in measurement readings. During exhaust emission testing and engine analysis, it will be found that pure digital meters cannot provide stable change values.
Fluke has overcome the shortcomings of digital watches and replaced them with analog/digital combination watches. It has the advantages of both digital meters and analog meters for dynamic measurement.
