Drive Characteristics; Overcurrent Protection; Drive Capacity; Using Vector Control - Toshiba H7 Operation Manuals

Drive Characteristics

Overcurrent Protection

Each H7 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 120% of the specified range for a limited amount of time as
indicated in Appendix D on pg.
nuisance over-current trips (see F601).
When using the drive for an application that controls a motor which is rated significantly less than the
maximum current rating of the drive, the over-current limit (Thermal Overload Protection) setting will
have to be changed to match the application. For further information on this parameter, see
Thermal Protection

Drive Capacity

The H7 ASD must not be used with a motor that has a significantly larger capacity, even if the motor is
operated under a small load. A drive being used in this way will be susceptible to the high-output peak
current which may result in nuisance tripping.
Do not apply a level of input voltage to a drive that is beyond that which the drive 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 H7 ASD while maintaining its robust
performance.
Vector Control is not capable of operating multiple motors connected in parallel.
See F015 on pg. 53

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.
22
203. Also, the Overcurrent Stall Level
#1.
for further information on using Vector Control.
may be adjusted to help with
Electronic
H7 ASD Operation Manual