Hitachi SJ700-4000HFU2

Chapter 4 Explanation of Functions
4-36
(3) Restarting methods
- Restart with matching frequency
The inverter detects the frequency and rotation direction based on the residual voltage in the motor, and then
restarts the motor based on the detected frequency.
- Restart with input frequency
The inverter starts the output with the frequency specified for the start frequency selection (b030), searches for
the point where the frequency and voltage are balanced while keeping the current at the restart current level
(b028), and then restarts the motor.
If the inverter trips when it restarts the motor in this way, reduce the setting of "b028".
- After the inverter output has been shut off, the digital operator continues to display until the
inverter restarts the motor operation.
4.2.28 Input/Output phase loss protection
(1) Input phase loss protection
The input phase loss protection function gives a warning when phase loss power
is input to the inverter.
Item
Function code
Data
Description
Input phase loss detection enable
b006
00
Disabling the protection
01
Enabling the protection
An phase loss power input may cause the following conditions, resulting in an inverter failure:
- The ripple current increases in the main capacitor, and the capacitor life will be shortened significantly.
- When the inverter is connected to a load, the internal converter or thyristor of the inverter may be damaged.
(2) Output phase loss protection
The output phase loss protection function gives a warning when output state on
the inverter is phase loss.
Item
Function code
Data
Description
Output loss detection
enable
b141
00
Disabling the protection
01
Enabling the protection
Output loss detection
sensibility
b142
1~100%
Detection sensibility of phase loss detection
An output phase loss may cause the motor is not running smoothly.
When you choose the size smaller capacity motor than the inverter capacity, phase loss warning may occur without
output phase loss. In this case, you should decrease the sensibility at b142 or set b141 = 00.
b006: Input phase loss detection enable
Related code
FW
FRS
b028
Output current
Inverter output
frequency
Deceleration according to the
setting of "b029"
Frequency selected as the setting
of "b030"
b003
Motor speed
b141: Output phase loss detection enable
b142: Output loss detection sensibility
Related code