Product Manual

SQ, SQE applications
SQ, SQE, CU 331, and SP
2
8
Constant-pressure control with CU 301,
residential water supply
The system maintains a constant pressure within the
maximum pump performance in spite of a varying
water consumption.
The pressure is registered by the pressure sensor and
transmitted to the CU 301. The CU 301 adjusts the
pump performance accordingly.
Function
When a tap is opened the pressure in the tank will start
to drop. At a flow lower than approximately 1 gpm
(0.18 m
3
/h), the pressure will drop slowly.
When the pressure in the tank is 7 psi (0.5 bar) below
setpoint, the pump will start. The pump will run until the
pressure is 7 psi (0.5 bar) above setpoint. This way of
operation is called on/off operation.
At a flow higher than approximately 1 gpm (0.18 m
3
/h),
the pressure will drop quickly and the pump will start
immediately and maintain a constant pressure.
During operation, the CU 301 will regulate the pump
speed to maintain a constant pressure. If there is no
consumption, the pump will boost the pressure to 7 psi
(0.5 bar) above setpoint and stop after a few seconds.
Fig. 6 Application example: Constant-pressure control with CU 301 - residential water supply
TM03 3429 0406
Recommended min. 20 inches
(0.5 m)
Min. 20 inches (0.5 m)
1Pump, SQE
2Cable
3Cable clips
4 Pressure tank, 2 gal (8 liters)
5 Control unit, CU 301
10 Pressure sensor, 0-120 psi (0-6 bar)
14 Pressure gauge
18 Tap
21 Mains connection
22 Riser pipe
30 Safety cable
31 Wire clamp
Pos. Part Type No. of units Product number Unit price Total price
1Pump SQE
2 Cable
3 Cable clips
4 Pressure tank 2 gal (8 liters)
5 Control unit CU 301
10 Pressure sensor 0-120 psi (0-6 bar)
14 Pressure gauge
30 Safety cable
31 Wire clamp