Pressure Tank
The SubDrive needs only a small pressure tank to maintain constant pressure. (See table below for recommended
tank size.) For pumps rated 2,5 m³/h or more, a slightly larger tank is recommended for optimum pressure regulation.
The SubDrive can also use an existing tank with a much larger capacity.
The minimum supply pipe diameter should be selected not to exceed a maximum velocity of 2,4 m/s (See
Table 6 below for minimum pipe diameter). The pressure tank pre-charge setting should be 70% of the
system pressure sensor setting as indicated in the following table.
Table 4: Minimum Pressure Tank Size (Total Capacity)
Maximum Velocity 2.4 m/s
min. Pipe Dia
(inches)
max. m³/h
1/2"
1,2
3/4"
2,4
1"
4,5
1-1/4"
6,8
1-1/2"
10
2"
17
2-1/2"
40
Table 6: Minimum Pipe Diameter
Pump Flow Rating
Controller Model
Minimum Tank Size
Less than 2,5 m³/h
SubDrive75
8 liters
SubDrive100
18 liters
SubDrive150
18 liters
2,5 m³/h and higher
SubDrive75
18 liters
SubDrive100
30 liters
SubDrive150
30 liters
Table 5: Pressure Tank Pre-charge bar
System Pressure
(bar)
(at Pressure Sensor)
Pressure Tank
Setting
(bar)
1,7
1,2
2
1,4
2,4
1,7
2,7
1,9
3
2,1
3,4 Factory Setting 2,3
3,7
2,7
4
2,8
4,4
3
4,7
3,3
5
3,7
Installation Procedure
1. Disconnect electrical power at the main breaker.
2. Drain the system (if applicable).
3. Install the pressure sensor at the pressure tank tee downstream of the
pressure tank. (The pressure tank should be between the pressure sensor
and the pump.) The pressure sensor has a 1/4-18 National Pipe Thread
(NPT) connection. The pressure sensor should not be installed in an inverted
orientation (upside down). Make sure the pressure sensor and tank are not
located more than 1m off the main piping.
4. Install the unit to the wall using adequate mounting screws (not included) as
shown in Figure 2. The top mounting holes are slotted in order to hang the
drive in place, while the bottom fasteners are inserted to secure the unit from
ever sliding up.
5. Remove the SubDrive lid as shown in Figure 2.
Lid Screws, (Quantity 2) Required
For Shipping; May Be Discarded
If Desired
Mounting Screw Locations
(User Supplied, Quantity 3)
Lid Screw (Required)
Figure 2: Shipping / Mounting / Lid Screws
14
Technical changes without notice / Techn. Änderungen vorbehalten / Modifications techniques réservées sans préavis / 5930
