The following modifications may be made during configuration:
If the expansion vessel is larger than 100 litres, set DS_A1 at OFF.
•
If you want the pumps to be exchanged every 24 hours and not at each restart, set DS_A2 at ON.
•
If you do not want protection against too rapid restarts, set DS_A3 at OFF.
•
If you do not want protection against lack of water, set DS_A4 at OFF.
•
If you want to bring the delay in switching off the pumps from 2 to 4 seconds, set DS A6 at OFF.
•
If you do not want to use the pump P1 set DS_A7 at ON.
•
If you do not want to use the pump P2 set DS_A8 at ON.
•
If you intend to use a set-point between 7 and 16 bar, set DS_B5 at ON.
•
If you intend to use pressure switches, set DS_B7 at OFF.
•
8.16
Regulating the rated current of the pumps (Imax), Set point (SP) and differential restarting pressure (DP)
With a straight tip screwdriver, position the indices in the centre of the graduated scales, as shown in Figure 53, so that:
Imax indicates the rated current of the installed pumps, which you can find on the pump data plate.
•
SP indicates the desired set point pressure.
•
DP is the pressure variation, in percentage of the set point, necessary to restart the pumps.
•
Attention, the differential restarting pressure is calculated as SP * DP. If the set point is 4 bar and DP is 50%, the pressure
differential RP is 2 bar.
8.17
System operation
Pressure switches:
The operating logic is the following:
Pressure switch connected to input B starts and stops Pump 1.
•
Pressure switch connected to input C starts and stops Pump 2.
•
Pressure sensor:
RP is the pressure differential, and indicates the pressure variation around the Set Point for which the pumps are switched on. In systems with a
display it is set directly. In systems without a display, DP is set as a percentage of the Set Point. RP = SP*DP. For further information see Figures
54 and 55.
The operating logic is the following:
The first pump starts when the pressure falls below the Set Point and it stops when it reaches the Set Point pressure + RP.
•
The second pump starts when the pressure falls below the Set Point minus RP, or 2% of the Set Point if vessels over 100 litres are
•
used. It stops when the set point pressure + RP is reached in the system.
Figure 53: Regulating the rated current SP and DP
Pressure boosting operation with pressure switches
Pressure switch
P1
B = CLOSED
Pressure switch
P2
C = CLOSED
Table 11: Pressure boosting operation with pressure switches
ENGLISH
Start
100
Stop
Pressure switch
B = OPEN
Pressure switch
C = OPEN