Toshiba H9 Installation And Operation Manual page 261

LED Display LCD Display
OC2
Overcurrent During
Deceleration
OC2P
Overheat During
Deceleration
OC3
Overcurrent During
Run
OC3P
Overheat During Run
OCA1 or OCL U-Phase Overcurrent • Low impedance at the U lead of the ASD output.
OCA2 or OCL V-Phase Overcurrent • Low impedance at the V lead of the ASD output.
OCA3 or OCL W-Phase Overcurrent • Low impedance at the W lead of the ASD output.
OCR
Dynamic Braking
Resistor Overcurrent
OH
Overheat
OH2
External Overheat
H9 ASD Installation and Operation Manual
Possible Causes
• Phase-to-phase short (U, V, or W).
• Deceleration time is too short.
• Motor/machine jammed.
• Mechanical brake engaged while the ASD is running.
• ASD current exceeds 340% of the rated FLA on ASDs that are 100 HP or
less during deceleration. On ASDs that are greater than 100 HP, it occurs
when the ASD current exceeds 320% of the rated FLA during deceleration.
• Cooling fan inoperative.
• Ventilation openings are obstructed.
• Internal thermistor is disconnected.
• Deceleration time is too short.
• DC Injection current is too high.
• ASD or the motor is improperly matched to the application.
• Load fluctuations.
• ASD is operating at an elevated temperature.
• ASD current exceeds 340% of the rated FLA on ASDs that are 100 HP or
less during a fixed-speed run or if during a fixed-speed run the ASD
overheats. On ASDs that are greater than 100 HP, it occurs when the ASD
current exceeds 320% of the rated FLA on a fixed-speed run.
• Cooling fan inoperative.
• Ventilation openings are obstructed.
• Internal thermistor is disconnected.
• Improper V/f setting.
• ASD or the motor is improperly matched to the application.
• ASD inability to discharge the bus voltage during regeneration.
• No dynamic braking resistor (DBR) installed.
• Deceleration time is too short.
• Improper DBR setup information.
• Defective IGBT7 (or IGBT7 ckt.).
• 3-phase input voltage is above specification.
• Cooling fan inoperative.
• Ventilation openings are obstructed.
• Internal thermistor is disconnected.
• Excessive-heat signature received at the TB3 – TH1(+) and TH1(-)
terminals. See F637 for setup information.
253