Input/Output Phase Loss Protection (B006 / B141,B142) - Hitachi SJ700D-004L Instruction Manual

Chapter 4
(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
restarts the motor operation.
FW
FRS
Output current
Inverter output
frequency
Motor speed
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
Input phase loss detection enable
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
Output loss detection
enable
Output loss detection
sensibility
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.
When the carrier frequency setting is too low, phase loss warning may occur without output phase loss. In this case,
you should adjust the carrier frequency setting.
The inverter detects that a phase loss on the output phases during the output frequency is between 5 and 100Hz．
b003
Function code
b006
Function code
b141
b142 1~100%
Explanation of Functions
b028
Deceleration according to the
setting of "b029"
Frequency selected as the setting
of "b030"
Data
00 Disabling the protection
01 Enabling the protection
Data
00 Disabling the protection
01 Enabling the protection
Detection sensibility of phase loss detection
4-36
until the inverter
Related code
b006: Input phase loss detection enable
Description
Related code
b141: Output phase loss detection enable
b142: Output loss detection sensibility
Description