Toshiba G7 manual ASD Characteristics, Over-current Protection, ASD Capacity, Using Vector Control

ASD Characteristics

Over-current Protection

Each G7 ASD model was designed for a specified operating power range. The ASD will incur a trip if the design specifications are exceeded.

However, the ASD may be operated at 110% of the specified output-current range continuously or at 150% for a limited amount of time as indicated in the section titled Current/Voltage Specifications on pg. 193. Also, the Overcurrent Stall Level may be adjusted to help with nuisance over-current trips (see F601).

When using the ASD for an application that controls a motor which is rated significantly less than the maximum current rating of the ASD, the over-current limit (Thermal Overload Protection) setting will have to be changed to match the application. For further information on this parameter, see Electronic Thermal Protection #1 on pg. 154.

ASD Capacity

The G7 ASD must not be used with a motor that has a significantly larger capacity, even if the motor is operated under a small load. An ASD being used in this way will be susceptible to a high-output peak current which may result in nuisance tripping.

Do not apply a level of input voltage to an ASD that is beyond that which the ASD is rated. The input voltage may be stepped down when required with the use of a step-down transformer or some other type of voltage-reduction system.

Using Vector Control

Using Vector Control enables the system to produce very high torque over the entire operating range even at extremely low speeds. Vector Control may be used with or without feedback. However, using feedback increases the speed accuracy for applications requiring precise speed control. Enabling the Automatic Energy Savings further increases the efficiency of the G7 ASD while maintaining its robust performance.

Vector Control is not capable of operating multiple motors connected in parallel.

See F015 on pg. 64 for further information on using Vector Control.

Local/Remote Operation

While running in the Local mode at a non-zero speed, if the RJ45 connector is removed from the EOI and then reinserted, the ASD remains in the Local mode even though the Local LED is off (press Run to illuminate the Local LED). The ASD output remains at the frequency of the Frequency Command field at the time of the disconnect so long as the connector is disconnected.

Once reinserted, the reference frequency that was loaded into the EEPROM (not RAM) before the disconnect will be the frequency to which the ASD output will return.

To prevent this condition, before disconnecting the RJ45 connector ensure that the ASD is off.

16 G7 ASD Operation Manual