AMETEK Lx Series II - Manual (Page 84)

User Manual Lx / Ls Series II
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ENTRY DESCRIPTION
of THD use the fundamental component (H1) of the voltage as the
denominator.
Lx/Ls units with firmware revision 0.88 or higher can be programmed
to use the fundamental component as the denominator. This mode
can only be programmed over the bus by sending the
“MEAS:THD:MODE FUND” command. At power up or after a reset
command, the mode will revert back to RMS.
CURR THD This readout displays the total current distortion for the selected
phase. The distortion calculation is based on the H2 through H50
with the RMS current in the denominator. Note that some definitions
of THD use the fundamental component (H1) of the current as the
denominator.
Lx/Ls units with firmware revision 0.88 or higher can be programmed
to use the fundamental component as the denominator. This mode
can only be programmed over the bus by sending the
“MEAS:THD:MODE FUND” command. At power up or after a reset
command, the mode will revert back to RMS.
PEAK CURR This readout reflects the peak current value detected at the output.
To measure inrush current for a unit under test, open the output
relay and reset the peak current value using the PEAK CURR
RESET entry. Then program the output voltage and frequency and
turn on the output relay. The peak current measurement will
continuously track the maximum current value detected until reset.
PHASE Relative voltage phase angle measurement with respect to phase A.
Update Program Functions from Measurement Screen
The Shuttles can be used to update voltage and frequency settings from the measurement
screen. While the measurement screens is visible, the Voltage and Frequency shuttle continue
to operate.
Frequency measurements on –LKS units
Lx or Ls models configured with the –LKS option used in a clock and lock configuration will not
accurately measure frequency if the programmed frequency of the master unit (-LKM) exceeds
2000 Hz unless the frequency setting of the
–LKS is set to the a value close to the programmed
frequency of the –LKM master unit. Setting the –LKS programmed frequency when it is operating
as a clock and lock auxiliary does not affect its actual output frequency as it is controlled by the
–LKM master unit. It does provide the controller with the required information to accurately
measure the frequency.