Toshiba H7 Operation Manuals page 191

EOI
Function
Display
OCA 1, U, V, or W Phase
2, or 3 Short Circuit
Motor
OCL
Overcurrent
(Startup)
OCR Dynamic Braking
Resistor
Overcurrent
OFF ST-to-CC
Opened
184
Description
This fault occurs in the
event of a short circuit at the
U (1), V (2), or W (3)
output leads of the ASD.
This fault occurs when a
short circuit is detected at
the output of the ASD.
This fault is caused by the
inability of the system to
adequately discharge the
bus voltage during
regeneration.
This fault is caused by the
ST-to-CC connection being
open.
Possible Causes
• Output resistance of the U,
V, or W leads of the ASD
are not within the
acceptable range.
• Output resistance of the U,
V, or W leads of the ASD
are not within the
acceptable range.
• No dynamic braking resistor
(DBR) installed.
• Deceleration time is too
short.
• Improper DBR setup
information.
• Defective IGBT7 (or
IGBT7 ckt.).
• Excessive input voltage.
• ST-to-CC connection is
open.
• (If applicable) MS1 AUX is
defective, inoperative, or
there is an open circuit in
the MS1 AUX circuit (see
Installation Notes on pg. 6).
Corrective Action
• Ensure that the ASD
output and the motor are
connected correctly.
• Disconnect the motor
from the ASD and retry.
• Replace the applicable
IGBT (U, V, or W).
• Contact your Toshiba
distributor for repair
information.
• Ensure that the output of
the ASD is correctly
connected to the motor.
• Decrease the output short
circuit detection pulse on-
time settings of F614.
• Install a DBR.
• Extend the deceleration
time.
• Ensure that the DBR
setup information is
correct (program ⇒
protection parameters ⇒
dynamic braking).
• Increase the value of the
DBR installed.
• Replace IGBT7.
• Ensure that the 3-phase
input voltage is within
established parameters.
• Close the ST-to-CC
connection.
• Confirm that the MS1
AUX circuit is
functioning properly.
• Remove the ST-to-CC
requirement via Program
⇒
Terminal Selection
Parameters ⇒ Input
Special Functions ⇒ ST
Signal Selection ⇒ ST-
CC Not Required.
H7 ASD Operation Manual