Toshiba H9 - Manual (Page 261)

H9 ASD Installation and Operation Manual 253
OC2
Overcurrent During
Deceleration
• 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.
OC2P
Overheat 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.
OC3
Overcurrent During
Run
• 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.
OC3P
Overheat During 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.
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
• 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.
OH
Overheat
• Cooling fan inoperative.
• Ventilation openings are obstructed.
• Internal thermistor is disconnected.
OH2
External Overheat
• Excessive-heat signature received at the TB3 – TH1(+) and TH1(-)
terminals. See F637 for setup information.
LED Display LCD Display Possible Causes