Technical data

20 U1401A User’s and Service Guide
1Getting Started
Display selection with the Hz key
The frequency measurement function is able to detect the
presence of harmonic currents in neutral conductors and
determines, whether these neutral currents are the result of
unbalanced phases or non- linear loads. Press to enter
the frequency measurement mode for current or voltage
measurements. The voltage or current values will be
displayed on the secondary display and the frequency values
on the primary display. Press this key again to step through
frequency (Hz), duty cycle (%), or pulse width (ms). This
allows simultaneous monitoring of real- time voltage or
current with frequency, duty cycle, or pulse width.
After you press and hold for more than one second,
the primary display will revert to voltage or current
measurement values.
Table 1 - 9 Measurement functions and corresponding display selection with the Hz key
Measurement function Primary display Secondary display
AC voltage Frequency (Hz) AC voltage
Duty cycle (%)
Pulse width (ms)
DC voltage Frequency (Hz) DC voltage
Duty cycle (%)
Pulse width (ms)
AC+DC voltage Frequency (Hz) AC+DC voltage
Duty cycle (%)
Pulse width (ms)
AC current Frequency (Hz) AC current
Duty cycle (%)
Pulse width (ms)