Toshiba H9 operation manual OCA1 or OCL, OCA2 or OCL, OCA3 or OCL

LED Display	LCD Display		Possible Causes
OC2		•	Phase-to-phase short (U, V, or W).
	Overcurrent During	• Deceleration time is too short.
	Deceleration
		•	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		•	Cooling fan inoperative.
	Overheat During	• Ventilation openings are obstructed.
	Deceleration
		• 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		•	Load fluctuations.
	Overcurrent During	• ASD is operating at an elevated temperature.
	Run
		• 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		•	Cooling fan inoperative.
	Overheat During Run	•	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		•	ASD inability to discharge the bus voltage during regeneration.
	Dynamic Braking	• No dynamic braking resistor (DBR) installed.
	Resistor Overcurrent
		• Deceleration time is too short.
		• Improper DBR setup information.
		• Defective IGBT7 (or IGBT7 ckt.).
		• 3-phase input voltage is above specification.
OH		•	Cooling fan inoperative.
	Overheat	• 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.

H9 ASD Installation and Operation Manual 253