Max Frequency
The Max Frequency should be set to the maximum output frequency that the pumps should be allowed to run. Contact
your pump and motor manufacturer for operation above 60 Hz.
PID Proportional Term
The PID Proportional Term is intended to be adjusted by
advanced
users only. The PID Proportional Term is used to
adjust the reaction of the output frequency to changes in the system pressure. Decreasing the PID Proportional Term
will allow the lead VFD to make larger corrections to the output frequency with differences between the Set Pressure
and actual system pressure. Increasing the PID Proportional Term will allow the lead VFD to make smaller corrections
to the output frequency with differences between the Set Pressure and actual system pressure.
PID Integral Term
The PID Integral Term is intended to be adjusted by
advanced
users only. The PID Integral Term is used to adjust how
quickly the output frequency reacts to changes in the system pressure. Decreasing the PID Integral Term will allow
the lead VFD to make quicker corrections to the output frequency with differences between the Set Pressure and
actual system pressure. Increasing the PID Integral Term will allow the lead VFD to make slower corrections to the
output frequency with differences between the Set Pressure and actual system pressure.
1st Accel Time
Set the 1st Accel Time to the rate at which the output frequency will accelerate from 0 Hz to the Accel 2 Switchover
Frequency. This time is based on the time the VFDs would take to accelerate from 0 Hz to 60 Hz. Example: If the
pump is required to accelerate from stop to 30 Hz in 1 second the 1st Accel Time should be set to 2 seconds.
1st Decel Time
Set the 1st Decel Time to the rate at which the output frequency will decelerate from the Accel 2 Switchover
Frequency to a stop. This rate is based on the time the VFDs would take to decelerate from 60 Hz to 0 Hz. Example: If
the pump is required to decelerate from 30 Hz to a stop in 4 seconds the 1st Decel Time should be set to 8 seconds.
Accel 2 Switchover Frequency
The Accel 2 Switchover Frequency should be set to the frequency at which the acceleration and deceleration rates
change. This is typically used on submersible type pumps, where the manufacturer requires a fast acceleration from a
stop to 30 Hz for proper thrust bearing operation.
Accel/Decel Time
Set the Accel/Decel Time to the rate at which the output frequency will change as the VFDs are operating above
the Accel 2 Switchover Frequency. This time is based on the time the VFDs would take the accelerate or decelerate
between 0 Hz to 60 Hz.
High Pressure
Set the High Pressure Alarm setting to the pressure at which the VFDs outputs will shut off due to high system
pressure. There is a 2 second delay before the VFDs will activate the High Pressure Alarm. If system pressure drops
below the High Pressure alarm setting for 10 seconds, the high pressure alarm will automatically reset and normal
operation of the VFDs will resume.
Run Dry Pressure
Set the Run Dry Pressure to the low pressure setting that will indicate the pumps cannot build pressure due to the
lack of supply water. The VFDs must be running at maximum output frequency and the system pressure must be
below the Run Dry Pressure for the amount of time set in Run Dry Delay Time for the VFDs to stop due to a Run Dry
Alarm.
Run Dry Delay Time
Set the Run Dry Delay Time to the amount of time the VFDs must be running at maximum output frequency while the
system pressure is below the Run Dry Pressure, before the VFDs will stop due to a Run Dry alarm.
Run Dry Restart Time
Set the Run Dry Restart Time to the amount of time the VFDs will remain stopped due to a Run Dry alarm, before
restarting. This time allows the well or water source to “recharge” before the system restarts. If a manual restart is
desired, set the Run Dry Restart Time to “0.0”. For a manual restart of the system, the “ESC” button must be pressed
for 2 seconds, or the power must be cycled. The display will indicate “Run Dry Fault” if a manual restart is required.
Parameter Setup List
VARIO
speed
®
3R Duplex User Manual
9
