Fluke 87V-MAX Product Manual - Page 31

87 Users Manual Use the Touch Hold mode (see item 10) to make audible diode tests. When the test leads are placed across the diode, a good diode or transistor junction will cause the meter to beep (and update the display) in the forwardbiased direction and remain silent in the reverse-biased direction. A short or resistance below about 30 kΩ will cause a beep in both directions. If an open is detected, the meter will remain silent in both directions. Using the Analog Display The analog display is easy to use and interpret. It functions much the same as the needle on an analog meter without the mechanical overshoot inherent in needle movements. The analog display is especially useful for peaking and nulling, and observing rapidly changing inputs. The analog display response time is fast, and it can be used to make approximate adjustments quickly. The 4000-count digital display can then be used for final adjustment. The analog display can also be used for limited diagnostic purposes. In situations where rapidly fluctuating signal levels make the digital display useless, the analog display is ideal. Like the needle on a Volt-ohm-milliammeter (VOM), the analog display excels at displaying trends, or slowly changing signals. Many diagnostic routines using 24 the analog display require practice. You will usually be looking for good or bad signal patterns that occur over some span of time. Noisy resistance measurements, for instance, create such patterns. Therefore, familiarity with analog display response and movement is necessary to accurately interpret a signal pattern. Compare the analog display response when making measurements on a unit known to be good, to the analog display response when making measurements on a faulty unit. Using the MIN MAX Recording Mode The MIN MAX Recording mode can be used to catch intermittents and turn on or turn off surges, verify performance, measure while you are away ("baby sit"), or take readings while you are operating the equipment under test and cannot watch the meter. The audible Min Max Alert indicates when a new minimum or maximum value has been recorded. You can select either a 100 millisecond, 1 millisecond (Peak), or 1 second (high accuracy) "response time" for recording minimum and maximum readings. The response time is the length of time an input must stay at a new value to record the full change. The 100 millisecond response time is best for recording power supply surges, inrush currents, and finding MyFlukeStore Find QuaSlhitoypPforordFulucktespOrondliuncetsato:nline awt:ww.wGwlo. balTestSupply.com.com [email protected]