Two common factors that will affect the accuracy of a phasemeter are distortion and/or broadband noise present on either or both of the input signals. A unique circuit design used in the 6620 significantly reduces any effects that may be caused by these two factors.
Another problem found in most phasemeters is the inability to respond to very small phase angles, resulting in fluctuations or inconsistencies in the meter reading (sometimes referred to as ambiguity). To overcome this problem, the 6620A uses a design that eliminates any ambiguities that may occur at readings near 0°, 180° and 360°, and allows measurements as small as 0.01° to be made.
The 6620 employs a technique that eliminates phase reading errors usually associated with component drift called Automatic Meter Correct (AMC). AMC provides instant correction of phase readings for zero and full scale errors, making phase measurements more accurate and reliable.
The Model 6620 provides a RELATIVE phase measurement mode which allows the monitoring of phase deviations without having to make unwanted calculations. Also provided are an automatic selection of input voltage range, front panel indicators to indicate a too low/high input voltage range, and an analog output for use with an external meter or strip chart recorder.
The 6620 is the ideal instrument for precision phase angle measurements and provides more performance/dollar than any other phasemeter in its class. A broad range of applications include monitoring servo control systems, low impedance measurements, adjustment of crystal resonance, testing and adjustment of filter networks, controlling laser trimming of resistor networks, measurements in ac power systems, secondary standard and general testing and measurement.