Mitsubishi Electric FR-F820-00046, Инструкция по эксплуатации

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Causes and corrective actions Protective functions
6 - 22
Operation panel
indication
E.UVT FR-LU08 Under Voltage
Name Undervoltage (Standard models only)
Description
If the power supply voltage of the inverter decreases, the control circuit will not perform normal
functions. In addition, the motor torque will be insufficient and/or heat generation will increase.
To prevent this, if the power supply voltage decreases to about 150 V AC (300 V AC for the 400 V
class) or below, this function shuts off the inverter output.
When a jumper is not connected across P/+ and P1, the undervoltage protective function is
activated.
When undervoltage protection is activated, the IPF signal is output.
(Refer to page 5-415, page 5-423.)
Check point
Check if a high-capacity motor is driven.
Check if the jumper is connected across terminals P/+ and P1.
Corrective action
Check the power supply system equipment such as the power supply.
Do not remove the jumper across terminals P/+ and P1 except when connecting a DC
reactor.
If the problem still persists after taking the above measure, contact your sales
representative.
Operation panel
indication
E.ILF FR-LU08 Input phase loss
Name Input phase loss (Standard models only)
Description
When Pr. 872 "Input phase loss protection selection" is enabled ("1") and one of the three-phase
power input is lost, the inverter output is shut off. This protective function is not available when
Pr. 872 is set to the initial value (Pr. 872 = "0"). (Refer to page 5-163)
Check point Check for a break in the cable for the three-phase power supply input.
Corrective action
Wire the cables properly.
Repair a break portion in the cable.
Operation panel
indication
E.OLT FR-LU08 Stall prevention STP
Name Stall prevention stop
Description
If the output frequency has fallen to 0.5 Hz by stall prevention operation and remains for 3 s, a
fault (E.OLT) appears and the inverter trips. OL appears while stall prevention is being activated.
During speed control, a fault (E.OLT) appears and the inverter trips if the frequency value
converted from the motor rotation speed drops to 1.5 Hz or lower by stall prevention operation
and the output torque exceeds the Pr. 874 "OLT level setting" (refer to page 5-180) and remains
there for 3 s.
Check point
Check the motor for the use under overload.
Check that the Pr. 874 values are correct.
(Check the Pr. 22 "Stall prevention operation level" setting under V/F control and Advanced
magnetic flux vector control.)
Check if a motor is connected under PM motor control.
Corrective action
Reduce the load.
Change the Pr. 22, and Pr. 874 values. (Check the Pr. 22 setting under V/F control and
Advanced magnetic flux vector control.)
For a test run without connecting a motor, select the PM motor control test operation. (Refer
to page 5-42.)
Also check that the stall prevention (overcurrent) warning (OL) or the stall prevention
(overvoltage) warning (oL) countermeasure is taken.
V/F V/F V/F Magnetic flux Magnetic flux Magnetic flux
PM PM PM