Fuji Electric FRENIC-AQUA series, User Manual

Page: 17 / 751

1-2
„
System protection function
z Slow flow rate function
The inverter can be stopped when the discharge rate becomes low due to increase of pump
discharge pressure. Facility having a bladder tank can make the stoppage period longer by
applying pressure immediately before stoppage, which realizes energy-saving operation.
z Dry pump detection
Pump dry condition can be detected from PID deviation value by setting the output frequency,
output current, and flow rate sensor value. Water leakage and pressure drop due to impeller
damage can be detected as well. You can choose whether the inverter will stop operation by alarm
or continue to operate while outputting alarm.
z Acceleration and deceleration at initial stage
When a pump such as a deep well pump is operated at low speed over a long period of time, the
pump may be damaged since the load current is large in the low-speed range. It is possible to
provide acceleration/deceleration time specific to the low-speed range in order to avoid prolonged
operation.
Small water
volume
Pressurized operation
Past
Freque
ncy
Stop time increases, thereby maximizing energy savings.
Small water
volume
Initial
deceleration time