Multimeter functions

Modern digital multimeters have many abilities, there are a wide range available to suit most engineers needs. These start from basic models costing only a few Pounds Sterling which are capable of measuring voltage, resistance and current, to expensive and exotic meters.

The more expensive meters are capable of performing not only the three functions mentioned above but depending on the needs of the service technician there are meters to measure capacitance, frequency, temperature, transistor specifications etc.

Functional Description

The multimeter is one of the single most useful instruments you will ever use for testing electrical circuits.

Enabling you to: -

• Measure Voltage in AC and DC circuits.

• Measure current flow AC and DC circuits

• Measure Resistance of the complete circuit or individual components

• Measure Transistor Gain

• Perform Diode tests

• Measure Temperatures etc.

For the purposes of this section you will need only a basic model which will give more than adequate results.

When you are unsure about any functions in the meter read the supplied manual to familiarise yourself with it. This will help to avoid expensive and possibly fatal mistakes.

ALWAYS

Ensure the multimeter selector is set to the correct position for the work to be carried out.

NEVER Connect a meter to a live circuit when it is set to read Ohms

The first three items listed below will take place, plus any combination of the other items listed could occur.

• Short out the device under test.

• Cause a surge of power through the multimeter.

• Increase the flow of current through the circuit.

• Possibly cause damage to the circuit under test.

• Blow the protection device in the meter.

• Cause irreparable damage to the meter.

• Injure or possibly Kill You.

NEVER Try to measure the voltage drop across a component in a circuit under test with the multimeter on the Amps measuring range.

The following will happen.

• Short circuit the component being tested.

• Cause a surge of power to flow through the circuit.

• Increase the possibility of major damage to components in the device being tested.