Regulating The Rated Current Of The Pumps (Imax), Set Point (Sp) And Differential Restarting Pressure (Dp); System Operation; Pressure Switches; Pressure Sensor - DAB E.Box Plus Installations- Und Wartungsanleitungen

The following modifications may be made during configuration:
If the expansion vessel is larger than 100 litres, set DS_A1 at OFF.
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If you want the pumps to be exchanged every 24 hours and not at each restart, set DS_A2 at ON.
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If you do not want protection against too rapid restarts, set DS_A3 at OFF.
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If you do not want protection against lack of water, set DS_A4 at OFF.
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If you want to bring the delay in switching off the pumps from 2 to 4 seconds, set DS A6 at OFF.
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If you do not want to use the pump P1 set DS_A7 at ON.
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If you do not want to use the pump P2 set DS_A8 at ON.
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If you intend to use a set-point between 7 and 16 bar, set DS_B5 at ON.
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If you intend to use pressure switches, set DS_B7 at OFF.
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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.
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SP indicates the desired set point pressure.
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DP is the pressure variation, in percentage of the set point, necessary to restart the pumps.
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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.
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Pressure switch connected to input C starts and stops Pump 2.
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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.
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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
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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