Input Phase Loss Protection; Output Phase Loss Protection - Hitachi P1 Basic Instruction Manual

INPUT PHASE LOSS PROTECTION

When [bb-65] input phase loss selection is set to 01, when a missing phase is detected in input line, the inverter turns OFF its output.
This protection function is used to prevent system failure due to unstable motor operation when a phase loss occurs by breakage of
the input power cable.
When the input phase loss protection function has been enabled, an input phase loss error [E024] will occur if a phase loss state due
to disconnection or breakage of the input power cable continues for 1 second or more.
When 3-phase AC is not supplied to power supply terminals R, S, and T, such as in cases where DC voltage is supplied to R and T or
between P and N of the inverter, this function is disabled regardless of the setting for [bb-65].
Function
Input phase loss protection

OUTPUT PHASE LOSS PROTECTION

While operating in closed loop mode (AA121 = 10) this protection function should be disabled due to 0hz load floating. The motor
torque proving, and speed deviation protection functions will provide the protection function.
When the output phase loss selection [bb-66] is set to 01, when a loose connection or disconnection of output line, disconnection
inside the motor, etc. is detected, the inverter turns OFF its output. Detection of phase loss state is executed in the section between
5Hz to 100Hz.
When the output phase loss protection function has been enabled, an output phase loss error [E034] will occur if a phase loss caused
by disconnection or breakage of the motor cable continues.
If the capacity of the drive motor is smaller than that of the inverter, the inverter may detect an output phase loss erroneously. In this
case, decrease the value of [bb-67] or set [bb-66] to 00.
If the carrier frequency [bb101] is low, the inverter may detect an output phase loss mistakenly. It may improve by increasing the
value of the carrier frequency [bb101].
Function
Output phase loss protection
Output phase loss detection sensitivity
Parameter
bb-65
Parameter
bb-66
bb-67
Page 37
Example Value
0 = disabled
1 = enabled
Example Value
0 = disabled
1 = enabled
1 ~ 100%