Toshiba W7 Manuale Utente

148

W7 ASD Installation and Operation Manual

ASD Overload

Load requirement in excess of 
the capability of the ASD.

• The carrier frequency is too high.

• An excessive load.

• Acceleration time is too short.

• DC damping rate is set too high.

• The motor is starting into a spinning load after a 

momentary power failure.

• The ASD is improperly matched to the application.

Motor Overload

Load requirement in excess of 
the capability of the motor.

• V/f parameter improperly set.

• Motor is locked.

• Continuous operation at low speed.

• The load is in excess of what the motor can deliver.

Resistor 
Overload

Excessive current at the 
Dynamic Braking Resistor.

• Deceleration time is too short.

• DBR configuration improperly set.

Overvoltage

DC bus voltage exceeds 
specifications.

• ASD attempting to start into a spinning motor after a 

momentary power loss.

• Incoming utility power is above the specified range.

• Decel time is too short.

• Voltage spikes at the 3-phase input; install inductive 

filter.

• DBR required.

• DBR resistance value is too high.

• DBR function is turned off.

• Overvoltage Stall feature is turned off.

• System is regenerating.

• Load instability.

• Disable the Ridethrough function (

).

Overtorque

Torque requirement in excess of 
the setting of parameter 

 or 

 for a time longer than the 

setting of parameter 

• ASD is not correctly matched to the application.

• Parameter 

 setting is too low.

• Obstructed load.

Control 
Undervoltage

Undervoltage condition at the 5, 
15, or the 24 VDC supply.

• Defective Control board.

• Excessive load on power supply.

• Low input voltage.

Reference Point

Two speed-reference frequency 
setpoint values are too close to 
each other.

• Two speed reference frequency setpoints are too close to 

each other (increase the difference).

Undercurrent

Output current of the ASD is 
below the level defined at 
parameter 

 and remains 

there for the time set at 
parameter 

.

* Reset ignored if active.