
Protective and Diagnostic Functions
7-
3
PUF
Main IGBT
Fuse
Blown
Fuse Blown
The fuse in the main circuit is
blown.
The output transistor has failed because
of a short-circuit or ground fault at the
Inverter output.
Check whether there is a short-circuit
between the following terminals. A
short-circuit will damage the output
transistor:
B1 (
3)
←→
U, V, W
←→
U, V, W
Replace the Inverter after correct-
ing the cause.
OV
DC Bus
Overvolt
Main Circuit Overvoltage
The main circuit DC voltage
exceeded the overvoltage detection
level.
200 V Class: Approx. 410 V
400 V Class: Approx. 820 V
(E1-01
≥
400 V)
Approx. 720 V
(E1-01 < 400 V)
The deceleration time is too short and
the regenerative energy from the motor
is too large.
Increase the deceleration time or
connect a braking resistor (or
Braking Resistor Unit). Alterna-
tively, enable (set to 1) the stall
prevention selection during decel-
eration (L3-04).
Motor ground fault
(Ground fault current flowed to the
capacitor in the control circuit of the
Inverter through the power supply.)
Check the output cable, relay ter-
minal, or motor terminal box and
correct the cause of ground fault.
Incorrect constant setting for speed
search
(The speed search can be performed
during momentary power loss recovery
and auto restart after a fault.)
• Use the speed search function.
• Adjust the settings of the Speed
search operating current (b3-02)
and Speed search deceleration
time (b3-03).
• Use the estimated speed search
function. (Autotuning for motor
line-to-line resistance is
required.)
Improper PG cable connection
(PG noise, PG disconnection)
Check to see if the PG cable is
connected properly.
The regenerative energy when an over-
shoot occurs after acceleration is com-
pleted is too large.
In vector control, enable (set to 1)
the overvoltage inhibit selection
(L3-11).
The power supply voltage is too high.
Decrease the voltage so it’s within
specifications.
Table 7.1 Fault Displays and Processing (Continued)
Display
Meaning
Probable Causes
Corrective Actions
TOE-S616-60.1.book 3 ページ 2017年8月4日 金曜日 午後3時41分