Output Open Phase Detection; Ground Fault Detection - Omron VARISPEED L7 Manual

Output Open Phase Detection

This function detects an open output phase by comparing the output current value of each phase with the out-
put open phase detection level (5% of inverter rated current). The detection does not work when the output fre-
quency is below 2% of the base frequency.
Three settings are available:
L8-07=0, no output open phase detection
•
L8-07=1, the loss of one phase is detected only
•
L8-07=2, the loss of 2 or 3 phases is detected as well
•
The detection delay time can be set in parameter L8-20.
Related Parameters
Parameter
No.
L8-07
L8-20

Ground Fault Detection

This function detects the earth leakage current by calculating the sum of the three output currents. Normally it
should be 0. If the earth leakage current gets too high, the inverter output is switched off and a GF fault is
6
shown on the display. The fault contact is activated.
Related Parameters
Parameter
No.
L8-09
Precautions
It is not recommended to disable this function.
•
A Ground Fault can also be detected if the contactors at the inverter output are opened when the output is
•
still active. Therefore, to prevent false Ground Fault detection check the sequence and make sure, that the
output is switched of or base blocked before opening the contactors.
48
6-
Name
Output open-phase detection selection
Output phase loss detection time
Name
Ground detection selection
Control Methods
Change
Factory
Open
during
Setting
V/f Loop
Operation
Vector
2 No A
0.2 sec No A
Control Methods
Change
Factory
Open
during
Setting
V/f Loop
Operation
Vector
1 No A
Closed
Closed
Loop
Loop
Vector
Vector
(PM)
A A A
A A A
Closed
Closed
Loop
Loop
Vector
Vector
(PM)
A A A