Fuji Electric FRENIC-AQUA series, User Manual

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6.3 Details of Function Codes
6-187
Chap. 6
FUNCTION C
ODES
H98 Protection/Maintenance Function (Mode selection)
H98 specifies whether to enable or disable automatic lowering of carrier frequency, input
phase loss protection, output phase loss protection, judgment threshold on the life of DC link
bus capacitor, judgment on the life of DC link bus capacitor, DC fan lock detection, and
IP21/IP55 switching, in combination (Bit 0 to Bit 7).
Automatic lowering of carrier frequency (Bit 0)
This function should be used for important machinery that requires keeping the inverter
running.
Even if a heat sink overheat or overload occurs due to excessive load, abnormal ambient
temperature, or cooling system failure, enabling this function lowers the carrier frequency to
avoid tripping (OH1, OH3 or OLU). Note that enabling this function results in increased
motor noise.
Input phase loss protection (Lin) (Bit 1)
Upon detection of an excessive stress inflicted on the apparatus connected to the main circuit
due to phase loss or line-to-line voltage unbalance in the three-phase power supplied to the
inverter, this protection feature stops the inverter and displays an alarm Lin.
In configurations where only a light load is driven, phase loss or line-to-line voltage
unbalance may not be detected because of the relatively small stress on the
apparatus connected to the main circuit.
Output phase loss protection (OPL) (Bit 2)
Upon detection of output phase loss while the inverter is running, this feature stops the
inverter and displays an alarm OPL.
Where a magnetic contactor is installed in the inverter output circuit, if the magnetic
contactor goes OFF during operation, all the phases will be lost. In such a case, this
protection feature does not work.
Judgment threshold on the life of DC link bus capacitor (Bit 3)
Bit 3 is used to select the threshold for judging the life of the DC link bus capacitor--the
factory default level or a user-defined one.
Before specifying a user-defined threshold, measure and confirm the reference level
in advance.
Refer to H42.
Judgment on the life of DC link bus capacitor (Bit 4)
Whether the DC link bus capacitor has reached its life is judged by measuring the discharging
time after power OFF. The discharging time is determined by the capacitance of the DC link
bus capacitor and the load inside the inverter. Therefore, if the load inside the inverter
fluctuates significantly, the discharging time cannot be accurately measured, and as a result, it
may be mistakenly determined that the DC link bus capacitor has reached the end of its life.
To avoid such an error, you can disable the judgment based on the discharging time. (Even if
it is disabled, the judgment based on the "ON-time counting" while the voltage is applied to
the DC link bus capacitor is continued.)
For details about the life prediction function, refer to H42.
Since load may fluctuate significantly in the following cases, disable the judgment on the life
during operation. During periodical maintenance, either conduct the measurement with the
judgment enabled under appropriate conditions or conduct the measurement under the
operating conditions matching the actual ones.
• Auxiliary input for control power is used.
• An option card is used.
• Another inverter or equipment such as a PWM converter is connected to terminals of the
DC link bus.