Mitsubishi Electric FR-A800, Instruction Manual

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Protective functions Causes and corrective actions
FR-A800 6 - 23
Operation panel
indication
E.IPF FR-LU-08 Instant Pwr failure
Name Instantaneous power failure (Standard models and IP55 compatible models only)
Description
If a power failure occurs for longer than 15 ms (this also applies to inverter input shut-off ), the
instantaneous power failure protective function is activated to trip the inverter in order to
prevent the control circuit from malfunctioning. If a power failure persists for 100 ms or longer,
the fault warning output is not provided, and the inverter restarts if the start signal is ON upon
power restoration. (The inverter continues operating if an instantaneous power failure is within
15 ms
.) In some operating status (load magnitude, acceleration/deceleration time setting,
etc.), overcurrent or other protection may be activated upon power restoration.
When instantaneous power failure protection is activated, the IPF signal is output.
(Refer to page 5-562, page 5-571.)
Check point Find the cause of instantaneous power failure occurrence.
Corrective action
앫
Remedy the instantaneous power failure.
앫
Prepare a backup power supply for instantaneous power failure.
앫
Set the function of automatic restart after instantaneous power failure (Pr. 57).
(Refer to page 5-562, page 5-571.)
10 ms for IP55 compatible models
Operation panel
indication
E.UVT FR-LU-08 Under Voltage
Name Undervoltage (Standard models and IP55 compatible 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 5-562, page 5-571.)
Check point
앫
Check if a high-capacity motor is driven.
앫
Check if the jumper is connected across terminals P/+ and P1.
Corrective action
앫
Check the power supply system equipment such as the power supply.
앫
Do not remove the jumper across terminals P/+ and P1 except when connecting a DC
reactor.
앫
If the problem still persists after taking the above measure, contact your sales
representative.
Operation panel
indication
E.ILF FR-LU-08 Input phase loss
Name Input phase loss (Standard models and IP55 compatible 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 5-306)
Check point Check for a break in the cable for the three-phase power supply input.
Corrective action
앫
Wire the cables properly.
앫
Repair a break portion in the cable.