Operation - Brymen BM905s User Manual

4

4) OPERATION

CAUTION
Before and after hazardous voltage measurements, test the voltage function on a
known source such as line voltage to determine proper meter functioning.
VFD-ACV & VFD-Hz (Line Level)
+Hz
Function defaults at VFD-ACV
+Hz
. By default, voltage is set at 600V & 1000V two
auto-ranges to best cope with most Variable Frequency Drives (VFD) measurements.
High noise-rejection frequency measurement algorithm and Low-pass filter circuit are
permanently bundled with all the voltage and frequency function-ranges within this
rotary-switch position. Press the RANGE button momentarily to select other ranges
only when needed.
Hz Input sensitivity varies automatically with voltage range selected. 6V range has the
highest and 1000V range has the lowest. Press SELECT button momentarily toggles to
higher resolution VFD-Hz in main display. The display shows the selected voltage
range for about one second before displaying Hz readings. Pressing the RANGE
button momentarily repeatedly to display and select any other voltage range. If the Hz
reading becomes unstable, select higher voltage range to avoid electrical noise. If the
reading shows zero, select lower voltage range for better sensitivity.