YASKAWA FP65U T Series Installation & Primary Operation page 99

Code Name
LWT Low Water In Tank
NMS Setpoint Not Met
OD Output Disconnect
oH Heatsink Overheat
oH2 External Overheat (H1-XX=B)
oH3 Motor Overheat (PTC Input)
oL3 Overtorque 1
oL4 Overtorque 2
oS Overspeed
ov DC Bus Overvoltage
ovEr Too Many Parameters Changed
PASS Modbus Communication Test
PF Input Phase Loss
YASKAWA TOEPC7106171GA FP605 Drive Installation & Primary Operation
Causes
An external input has indicated that the water level in
the tank is too low in these conditions:
• Y4-24 = 2 [Low City Alarm Text = Low Water in
Tank]
• The terminal set for H1-xx = B8 or 1B8 [MFDI
Function Selection = Low City Pressure or !Low
City Pressure] activates
The feedback deviates from the setpoint at a level
more than Y1-15 [Maximum Setpoint Difference] for
the time set in Y1-16 [Not Maintaining Setpoint
Time].
The output circuit between the drive and the motor is
open, and the drive output current is less than 5% of
E2-01 [Motor Rated Current (FLA)].
The ambient temperature is high and the heatsink
temperature is more than the L8-02 [Overheat Alarm
Level].
An external device sent an oH2 alarm.
The thermistor wiring that detects motor temperature
is defective.
A fault occurred on the machine.
Example: The machine is locked.
A fault occurred on the machine.
Example: The machine is locked.
There is overshoot.
The drive output cable or motor is shorted to ground
(the current short to ground is charging the main
circuit capacitor of the drive through the power
supply).
The power supply voltage is too high.
Electrical interference caused a drive malfunction.
You tried to change more than 150 parameters.
The MEMOBUS/Modbus communications test is
complete.
There is a phase loss in the drive input power.
Loose wiring in the input power terminals.
The drive input power voltage is changing too much.
Unsatisfactory balance between voltage phases.
20 Troubleshooting
Possible Solutions
• Examine the pressure switch contact for correct operation.
• Examine control wiring to drive terminal strip from pressure
switch contact.
• Make sure that suction pressure is present with an isolated
measuring device.
• Increase the water level.
• Set Y4-22 [Low City On-Delay Time] and Y4-23 [Low City Off-
Delay Time] correctly.
• Deactivate the digital input terminals set to H1-xx = B8 or 1B8.
• Examine for a blocked impeller, over cycling, or broken pipe.
• Set Y1-15 and Y1-16 correctly.
• Close the disconnected output circuit between the drive and the
motor.
• If you do not use a motor disconnect, set Y4-42 = 0 [Disabled].
• Measure the ambient temperature.
• Increase the airflow around the drive.
• Install a cooling device (cooling fan or air conditioner) to
decrease the ambient temperature.
• Remove objects near the drive that are producing too much heat.
1. Find the external device that output the overheat alarm.
2. Remove the cause of the problem.
3. Clear the Overheat Alarm (oH2) [H1-xx = B] in MFDI
terminals S1 to S7.
Correct wiring errors.
Examine the machine and remove the cause of the fault.
Examine the machine and remove the cause of the fault.
Decrease C5-01 [ASR Proportional Gain 1] and increase C5-02
[ASR Integral Time 1].
1. Examine the motor main circuit cable, terminals, and motor
terminal box, and then remove ground faults.
2. Re-energize the drive.
Decrease the power supply voltage to align with the drive rated
voltage.
• Examine the control circuit lines, main circuit lines, and ground
wiring, and minimize the effects of noise.
• Find the source of the noise. If a magnetic contactor is the
source, use Surge Protective Device if necessary.
• Set L5-01 ≠ 0 [Number of Auto-Restart Attempts ≠ 0 times].
Make sure that parameters that do not have an effect on drive
operation are at their default settings.
Note:
• You can change 150 parameters maximum.
• If you change parameters that have dependencies, the drive
can detect ovEr when the number of changed parameters is
fewer than 150.
The PASS display will turn off after communications test mode is
cleared.
Correct errors with the wiring for main circuit drive input power.
Tighten the terminal screws to the correct tightening torque.
• Examine the input power for problems.
• Make the drive input power stable.
• Examine the input power for problems.
• Make the drive input power stable.
• If the input power supply is good, examine the magnetic
contactor on the main circuit side for problems.
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