How to Measure Resistance

To configure the electronic devices and matching circuits must know the resistance of their components. Sometimes it also becomes necessary to check the individual radio components (resistors, diodes, transformers of different function) on the resistance.

The item or item being tested for resistance disconnects the circuit. Start the measurement by turning instrument to measure the minimum resistance to the regime. If the readings are readable enough, you can step by step to move to higher value mode of resistance. Each meter has feelers. They are attached to the conclusions of the details. Before the measurements, it is necessary to read the instructions, especially what concerns the polarity. Polarity is important in measuring the resistance of semiconductor components.

The usual tester, MASTECH Voltmeter, (e.g. MASTECH MS6450 or MASTECH MS3302) can measure the resistance range from a few ohms to milliohms units. For higher resistances DC need additional power connection according to the instructions for the device. You can apply the calculation circuit resistance. For this item investigated include the circuit with a current source in series with an ammeter is included, and in parallel studied details - voltmeter. In this case, the resistance is calculated according to the formula: R = U / I, where R - voltage, U- resistance, and I - the current in the circuit.

Some radioactive elements (e.g. semiconductors) have different resistance for different directions of current. This should be considered when measuring by conducting reverse current measurement at lower values ​​of the applied voltage. Otherwise researched item may be damaged.