Franklin Electric Fhoton Drive Guide D'installation page 9

Underload (Dry Well)
The Fhoton™ Drive monitors both the motor load and rotor speed to electronically detect when the pump runs dry. At approximately 35
Hz (rotor speed) and above, the electronic dry well protection algorithm is active. If the motor load falls below the built-in, dry well trip
level while the rotor speed exceeds 35 Hz for a period of 3 seconds, the Fhoton™ drive will halt the motor. The red LED will begin a 1 flash
sequence and continue this flash sequence for a duration of 5 minutes. After which time, the drive will resume normal operation (see
Figure 2. Underload (Dry Well) Protection Algorithm).
Motor Loading
(%)
Underload Protection
Region For Dry Well
Flow Switch Protection
Region For Dry Well
Dry Well
Rotor Speed (Hz)
Figure 2. Underload (Dry Well) Protection Algorithm
Overvoltage
The Fhoton™ Drive monitors the DC input bus voltage for an overvoltage condition. If the voltage exceeds 420 volts, at any time, the
Fhoton™ drive will halt the motor. The red LED will begin a 2 flash sequence and continue this flash sequence for a duration of 3 cycles.
After which time, the drive will recheck the bus voltage. The voltage must drop below 410 volts before the drive will resume normal
operation; otherwise, the red LED flash sequence will continue.
Locked Rotor
The Fhoton™ Drive monitors both the motor load and rotor speed to electronically detect when the motor/pump is not rotating. If the
motor operates near maximum loading conditions, while the rotor speed is below the minimum operating frequency for a period of 3
seconds, the Fhoton™ drive will halt the motor. The red LED will begin a 3 flash sequence and continue this flash sequence for a duration
of 3 cycles. After which time, the drive will resume normal operation.
Low Flow Trip
The Fhoton™ Drive monitors the input flow switch to determine whether water is flowing (see 'Flow Switch' under 'Features'). If the flow does
not meet the minimum value to close the switch for a duration of 30 seconds, the Fhoton™ drive will halt the motor. The red LED will begin a 4
flash sequence and continue this flash sequence for a duration of 5 minutes. After which time, the drive will resume normal operation.
9