The Rolson M830 digital multimeter is a low-cost entry-level electronics instrument designed for measuring the full range of electrical units, including Direct Current (DC) voltage, Alternative Current (AC) voltage, Ohms (resistance) and Amperage (amps). The unit also includes diode bias and continuity test selections. Though low-cost, the device operates just as any other digital multimeter does, with the connections and dial settings being the same as well.
Pick up the red test lead wire and observe the two metal ends. One end will contain a short, spring-steel plug, while the other end will have a narrow, pointed probe extruding from the insulated plastic handle. If you will be measuring voltage or resistance, plug the short end of the test lead into the jack on the front panel of your M830 multimeter labelled "10ADC" where the ADC stands for "AC/DC." You'll touch the probes to the circuit or component during testing--black probe to the negative side and the red probe to the positive side.
Pick up the black lead wire and locate the plug end as you did with the red lead wire, then insert it into the jack on the front panel of your M830 multimeter labelled "COM" which stands for "Common," or "Ground." Again, you'll touch the probes to the circuit or component during testing.
Determine whether the power source you are measuring is Direct Current (DC) or Alternating Current (AC), and what the maximum voltage is for the circuit in question (6 volts, 10 volts, 120 volts, etc.). Direct Current is usually present in battery-powered equipment, or if a device has a wall-pack converter that converts household Alternating Current to Direct Current specifically for the device's requirements.
Turn the dial from the "OFF" position to the "ACV" (AC Voltage) if measuring Alternating Current, and set the dial to 150 volts if measuring a circuit that is 150 volts or less. Set the dial to 200 volts if measuring between 151 and 200 volts AC.
Turn the dial to the "DCV" sector on the panel if measuring DC volts, and set the meter to the voltage setting that matches or exceeds the level of DC volts you will be testing, just as you did when measuring AC volts as in Step 4.
Unplug the red lead wire from the meter, plug it into the jack labelled "V(ohm)ma" and set the dial to the sector in the lower left corner of the panel where you see the "Omega" (appears as a horseshoe) sign if measuring resistance in Ohms. Set the dial to the resistance level you are measuring, or one step higher than the maximum you are testing; either way will work properly.
Keep the red test lead wire in the "V(ohm)ma" jack and turn the dial to "DCA" if you desire to measure amperage in a Direct Current circuit, again setting the dial to match or exceed the maximum amperage the circuit should be producing.
Keep the red test lead wire in the "V(ohm)ma" jack and turn the dial to the diode/continuity sector if a component or diode is to be tested for an "open" circuit (you should hear a tone when you touch the probe to the component. If you don't, the component is burnt out). For a diode, you may have to switch the probes around on the legs of the diode to get an audible tone, as electricity flows through these in one direction only.
If measuring Alternating Current, never turn your meter to the Direct Current (DCV) sector, as this will permanently damage a digital multimeter. Likewise, if measuring Direct Current, never set the meter to the Alternating Current measurement sector. In the latter case, you won't get a reading at all.
Tips and warnings
- If measuring Alternating Current, never turn your meter to the Direct Current (DCV) sector, as this will permanently damage a digital multimeter. Likewise, if measuring Direct Current, never set the meter to the Alternating Current measurement sector. In the latter case, you won't get a reading at all.