7-2 Trips & Fault FindingAC30 series Variable Speed InverterUsing the Keypad to Manage TripsTrip MessagesIf the drive trips, then the display immediately shows a message indicating the reason for the trip. The possible trip messages are given in thetable below.ID Trip Name Possible Reason for Trip Criteria for Warning1 OVER VOLTAGE The drive internal dc link voltage is too high:• The supply voltage is too high• Trying to decelerate a large inertia load too quickly; DECEL TIME time too shortThe brake resistor is open circuitTo help prevent this trip, enable the DC Link Volts Limit featureInternal dc link voltage hasreached midway between theover voltage trip level and thedynamic braking resistor controlvoltage.2 UNDER VOLTAGE DC link low trip:• Supply is too low/power downInternal dc link voltage hasreached midway between thelowest expected instantaneousvoltage and the under voltagetrip level.3 OVER CURRENT The motor current being drawn from the drive is too high:• Trying to accelerate a large inertia load too quickly; ACCEL TIME time too short• Trying to decelerate a large inertia load too quickly; DECEL TIME time too short• Application of shock load to motor• Short circuit between motor phases• Short circuit between motor phase and earth• Motor output cables too long or too many parallel motors connected to the drive• FIXED BOOST level set too highThe over current trip makes up ofa multiple-attempt strategy.The warning is triggered if two ormore consecutive overcurrentevents are encountered (whereasfive consecutive events arerequired for a Trip to occur).4 STACK FAULT Stack self protection• Instantaneous overcurrent detected by the power stack. Refer to OVERCURRENTin this table.• Instantaneous over voltage event. Refer to OVER VOLTAGE in this tableNot applicable.5 STACK OVERCURRENT The motor current exceeded the capabilities of the power stack.• Instantaneous overcurrent detected by the power stack. Refer to OVERCURRENTin this table.Not applicable.6 CURRENT LIMIT V/Hz mode only: If the current exceeds 200% of stack rated current for a periodof 1 second, the drive will trip. This is caused by shock loadsNot applicable.
