INSTALLATION AND SETUP
Installation Process
Minimum Pressure Tank and Supply Pipe Sizing
A VFD system needs only a small pressure tank to maintain constant pressure, although a larger
tank may be used. If adding a SubDrive/MonoDrive to a conventional system with an existing large
tank, refer to
"Advanced Options" on page
When using a standard pressure sensor, system performance can be adjusted using the FE Connect
mobile app to select tank size. Refer to
The pressure tank pre-charge setting should be 70% of the targeted system pressure. To check the
tank's pre-charge, de-pressurize the water system by opening a tap with the drive off. Measure
with a pressure gauge at the inflation valve and make any necessary adjustments.
Refer to the following recommendations for best performance.
Submersible Pump Applications
Pump Flow Rating
Less than 12 gpm (45.4 lpm)
12 gpm (45.4 lpm) and higher
Surface Pump Applications
Maximum Pump Flow
10 GPM
20 GPM
30 GPM
40 GPM
Minimum Supply Pipe Sizes
The minimum supply pipe diameter past the pressure sensor (transducer) should be selected not
to exceed a maximum velocity of 8 feet per second (2.4 m/s) based on the flow rate of the system.
Maximum GPM (lpm)
11.0 (41.6)
19.6 (74.2)
30.6 (115.8)
44.1 (166.9)
78.3 (296.4)
176.3 (667.4)
16
38.
"Advanced Options" on page
VFD Model
SubDrive 15 or MonoDrive
SubDrive 20
SubDrive 30 or MonoDriveXT
SubDrive 50
SubDrive 15 or MonoDrive
SubDrive 20
SubDrive 30 or MonoDriveXT
SubDrive 50
Minimum Tank Size
2 gallons (7.6 liters)
4 gallons (15.1 liters)
4 gallons (15.1 liters)
8 gallons (30.3 liters)
Minimum Pipe Diameter
3/4"
1"
1-1/4"
1-1/2"
2"
2-1/2"
38.
Minimum Tank Size
2 gallons (7.6 liters)
4 gallons (15.1 liters)
4 gallons (15.1 liters)
8 gallons (30.3 liters)
4 gallons (15.1 liters)
8 gallons (30.3 liters)
8 gallons (30.3 liters)
20 gallons (75.7 liters)