62 HX7+ ASD Quick Start Guide
Alarms
Table 14 lists the alarm codes that may be displayed during operation of the HX7+ ASD. Each alarm code 
listed is accompanied by a description and a possible cause. In the event that the source of the malfunction 
cannot be determined, contact your the 
Toshiba Customer Support Center
 for further information on the 
condition and for an appropriate course of action.
The Alarms are listed in the top-down order that they are checked for activation. Only the first to be 
detected will be displayed on the Frequency Command screen.
Table 14. HX7+ Alarms.
Keypad 
Display
Function Description Possible Causes
CM1 Comm1 Error Internal communications error. • Improperly programmed ASD.
• Improper communications settings.
• Improperly connected cables.
CM2 Comm2 Error External communications error.
EMG Emergency Off Output signal from the ASD is 
terminated and a brake may be 
applied if so configured.
• Stop|Reset pressed twice at the keypad.
• EOFF command received remotely.
• ASD reset required.
MOFF Main 
Undervoltage
Undervoltage condition at the 
3-phase AC input to the ASD.
• Low 3-phase commercial power voltage too low.
OC Over Current ASD output current greater than 
F601
 
setting.
• Defective IGBT (U, V, or W).
• ASD output to the motor is connected incorrectly. 
Disconnect the motor and retry.
• ASD output phase-to-phase short.
• The ASD is starting into a spinning motor.
• Motor/machine jammed.
• Mechanical brake engaged while the ASD is starting or 
while running.
• Accel/Decel time is too short.
• Voltage Boost setting is too high.
• Load fluctuations.
• ASD operating at an elevated temperature.
*OH Overheat ASD ambient temperature 
excessive.
• ASD is operating at an elevated temperature.
• ASD is too close to heat-generating equipment.
• Cooling fan vent is obstructed (see Mounting the ASD 
on pg. 19).
• Cooling fan is inoperative.
• Internal thermistor is disconnected.
OJ Timer Run-time counter exceeded. • Type Reset required; select Clear run timer.
* Reset ignored if active.