Fault Diagnosis And Corrective Actions; General - YASKAWA V7 Technical Manual

Section 6. FAULT DIAGNOSIS AND CORRECTIVE ACTIONS

6.1 GENERAL

This section describes the alarm and fault displays, explanations for fault conditions and corrective
actions to be taken if the Drive malfunctions.
A failure in the Drive can fall into one of two categories, Alarm or Fault.
A blinking "Alarm" indication is a warning that a Drive trouble condition will soon occur, or that a
programming error has been made. The Drive will continue to operate during an "Alarm" indication.
A blinking "Minor Fault" indication is displayed during less serious faults, or when a problem exists in
the external circuitry. The Drive will continue to operate, and a "Minor Fault" contact will be closed if
a multi-function output is programmed for the condition.
A steady "Major Fault" indication is displayed when the Drive's Fault relay has tripped. The motor
coasts to a stop, and a fault signal output is present at control circuit terminals 18-20.
: ON : BLINKING
Table 6-1. Alarm Displays and Corrective Actions
Alarm Display
Digital RUN (Green)
Operator ALARM (Red)
Blinking
Blinking
Blinking
Blinking
: OFF
Drive
Explanation
Status
UV (Main circuit low voltage)
Main circuit DC voltage
drops below the low-voltage
detection level while the
drive output is OFF.
230V: Stops at main circuit
DC voltage below
approx. 200V
(160V for single-
phase)
460V: Stops at main circuit
DC voltage below
approx. 400 V
OV (Main circuit overvoltage)
Warning
Main circuit DC voltage
only.
exceeds the over voltage
Fault
detection level while the
contacts
drive output is OFF.
do not
Detection level: approx.
change
410V or more (approx.
state.
820V for 460V class).
OH (Cooling fin overheat)
Intake air temperature
rises while the drive
output is OFF.
Warning. OH3 (Drive overheat
Fault pre-alarm)
contacts OH3 signal is input.
do not
change
state.
6-1
Causes and
Corrective Actions
Check the following:
• Power supply voltage
• Main circuit power
supply wiring is
connected.
• Terminal screws are
securely tightened.
Check the power supply
voltage.
Check the intake air
temperature.
Release the input of
inverter overheat pre-
alarm signal.