The most common type is the handheld Digital Multimeter (DMM) shown here alongside my trusty Fluke, both referred to throughout this section. A Multimeter can be used to; n Check the continuity of a circuit or cable. n Check the earth continuity of an IRS. n Measure the voltage of a battery or other source. n Measure the amount of current flowing through a device, like an LNB. n Check if a cable or wire is conducting electricity or not. n Check if a PSU is working OK. Parts of a DMM The basic DMM has several main parts (DMM type dependant) and are used with measuring leads. n Display – this usually has 4 digits and can show a negative sign. Some displays are illuminated for better viewing in low light. n Selection Knob – to select the appropriate setting. n Hold Button (if applicable) – used to ‘hold’ the reading for viewing display after disconnection of probes. n Ports – connect leads as required for the setting.
n Is that power supply working OK? n Is that Class 1 or Class 11? n Are those T & K brackets far enough apart? n How many amps is a milliamp (mA)? n Do I need to earth that coax cable? All of these questions are answered in the Essential Principles 2-day course for installers. It says installers, but in fact it’s suitable for anyone who wants to know answers to the above. They are all covered in the Essential Principles 2-day training course along with so much more. In the meantime, here is a brief introduction to the use of a multimeter. The Multimeter A Multimeter is an electronic measuring instrument which can measure multiple things related to electricity (Voltage, Current and Resistance) and show the results on the display of a meter. It can be indispensable when diagnosing system problems. The multimeter replaces a Voltmeter, Ammeter and Ohmmeter (Resistance), hence it functions as multiple meters in one unit. Some modern Multimeters will also measure capacitance, frequency and temperature. In this article, we will only be considering the basic meter types.
Parts of a Multimeter
A Basic DMM
My Fluke DMM
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