Yaskawa Z1000U - Manual (Page 210)

A digital input set to 67H (MEMOBUS/Modbus
test) was closed while the drive was running
Stop the drive and run the test again.
Digital Operator Display Minor Fault Name
SrC
Phase Order Detection Fault
The phase rotation direction for the input power supply changed.
HOA Keypad Display Minor Fault Name
UL3
Undertorque Detection 1
Drive output current less than L6-02 for longer than L6-03 time.
Cause Possible Solutions
Inappropriate parameter settings Check parameters L6-02 and L6-03.
Load has dropped or decreased significantly Check for broken parts in the transmission system.
HOA Keypad Display Minor Fault Name
Uv
Undervoltage
One of the following conditions was true when the drive was stopped and a Run command was
entered:
• DC bus voltage dropped below the level specified in L2-05.
• Contactor to suppress inrush current in the drive was opened.
• Low voltage in the control drive input power. This alarm outputs only if L2-01 is not 0 and DC
bus voltage is under L2-05.
Cause Possible Solutions
Phase loss in the drive input power Check for wiring errors in the main circuit drive input power. Correct the wiring.
Loose wiring in the drive input power terminals
• Ensure the terminals have been properly tightened.
• Apply the tightening torque to the terminals as specified.
Refer to Main Circuit Wire Gauges and
Tightening Torque on page 72 .
There is a problem with the drive input power
voltage
• Check the voltage.
• Lower the voltage of the drive input power so that it is within the limits listed in the specifications.
Drive internal circuitry is worn
• Check the maintenance time for the capacitors (U4-05).
• Replace either the control board or the entire drive if U4-05 exceeds 90%. For instructions on
replacing the control board, contact Yaskawa or your nearest sales representative.
The drive input power transformer is too small and
voltage drops when the power is switched on
• Check for an alarm when the magnetic contactor, line breaker, and leakage breaker are closed.
• Check the capacity of the drive input power transformer.
Air inside the drive is too hot Check the temperature inside the drive.
The CHARGE light is broken or disconnected
Replace either the control board or the entire drive. For instructions on replacing the control board,
contact Yaskawa or your nearest sales representative.
HOA Keypad Display Minor Fault Name
WrUn
Waiting for Run
A Run command has been issued and the drive is waiting to begin running the motor.
Cause Possible Solutions
After a Run command has been entered, the drive
must wait for the time set to b1-11 to pass before
it can begin to operate the motor
This is not an error.
5.5 Alarm Detection
210 YASKAWA ELECTRIC TOEP C710636 10B Z1000U HVAC MATRIX Drive User Manual