Fullscreen HTML5Med Res (??MB)HTML4

Motech MT-4080A LCR meter Some digital multimeters have facilities for testing inductance, capacitance and resistance but none really do a good job for all three, particularly as far as inductance is concerned. This is where the Motech MT-4080A LCR meter comes into its own. T HE MT-4080A is a multimetersized instrument with a large liquid crystal display and eight pushbuttons on its control panel. As well, there is a three-way socket with large contacts to take the measurement adaptors. Of course, some components with suitable leads can be plugged straight in but most component measurements will be taken using one of the adaptors. All told, up to 10 component par­ ameters can be measured: AC impedance and DC resistance from zero up to 9999MΩ; serial and parallel inductance from 0.000µH up to 9999H; serial and parallel capacitance from 0.000pF to 9999F; equivalent series resistance (ESR) from zero to 9999Ω; Dissipation factor (for capacitors) from 0 to 9999; Quality factor (for inductors) from 0 to 9999; and phase angle from -180° to + 180°. 128 Not only can all these parameters be measured but you can also use one of five test frequencies: 100Hz, 120Hz, 1kHz, 10kHz and 100kHz. The two lower frequencies are important when measur­ing ESR of electrolytic capacitors while 100kHz is important when measuring small inductors and dissipation factor in the smaller capacitors. At most times though, the chosen test frequency is likely to be 1kHz. The test voltage level is also select­ able, at 1V, 250mV or 50mV RMS or 1V DC (for DC resistance measurements). Furthermore, if you are making measurements on a component that is varying, you can select fast or slow measurement speeds: 2.5 or 4.5 meas­ urements/second. The LCD panel will show two par­ ameters for each measure­ment, plus the signal level and frequency. For example, when measuring a capacitor Silicon Chip’s Electronics TestBench it will display the capacitance in pF, nF, µF or F (Farads) plus the Dissipation factor or ESR. Similarly, for an inductor, it will display the inductance in µH, mH or H (Henries) plus the Q or ESR. Accuracy of the MT-4080A is quoted as ±0.2%. The instru­ment also has a range hold and relative modes which can be handy when selecting components against a standard value. Two adaptors are available for measurements plus a shorting bar attachment. The first adaptor is a 4-wire probe for sur­face mount components while the second is a 4-wire probe for testing standard leaded components. Power comes from two AA cells which may either be alkaline or rechargeable NiMH. A constant current charger is also sup­plied. All told then, the Motech MT-4080A is a well-thought out instrument that is very straightforward to use. We used it in our laboratory for several weeks and found it a very reliable unit. The MT-4080A is priced at $1142 plus GST. For further information, contact Westek Industrial Pro­ ducts, Unit 2, 6-10 Maria Street, Laverton North, 3026. Ph (03) 9369 8802; fax SC (03) 9369 8006.