NP45-09 User’s Guide
37
example the start-up current in induction motors can be ten times the normal working
current. Inrush is a ‘single shot’ mode that records current and voltage Trends after a
current event has occurred. An Inrush occurs when the current waveform exceeds
adjustable limits. The Trends builds up from the right of the screen. Pretrigger
information allows you to see what occurred in advance of the inrush.
Trend display
Use the arrow keys in the inrush current function to adjust the trigger limits: expected
inrush time, nominal current, threshold and hysteresis. The maximum current
determines the vertical height of the current display windows. Threshold is the current
level that triggers the trend capture. The inrush time is the time between trigger and
the time that the current falls to the value indicated by Hysteresis and is indicated on
the trend display between two vertical markers. The screen header displays the rms of
all phases during the inrush time. If the Cursor is on, the rms measuring values at the
Cursor are displayed.
Function keys instruction:
【
F1
】
: Switch parameters to be displayed.
【
F2
】
: Access to inrush current events list
【
F3
】
: Open/ close cursor
【
F4
】
: Open/ close Zoom function
【
F5
】
: Switch between RUN and HOLD
