Xylem LOWARA SMB /HME Series, Инструкция по установке, эксплуатации и обслуживанию

Страница: 22 / 31

en
– Original instructions
22
Figure 10 shows the operating curves in the case of two pump units in pressure adjustment
mode.

The tank supplies water to meet the demand of the final user.

The first pump unit starts when the pressure drops below the PS value; the speed is adjusted
to keep the pressure constant as demand increases.

When demand decreases, the speed is reduced to minimum; at this point, one of the pump
units is deactivated.

If demand continues to increase and the pump unit reaches maximum speed, the second
pump unit is started and the speed is adjusted to maintain constant pressure.

If demand decreases further, the pump unit slows down, fills the tank and then stops when the
PS value is reached.
Figure 10: Operating mode
H Head Pmax Maximum pressure
Q
Flow
PS
Pressure setting value
5.2.1 Adjusting the frequency converter
1. To change the settings, refer to the Installation, Operation and Maintenance Manual of the
pump units in the Smart Pump Range.
2. Use the buttons of the frequency converter to set a new pressure adjustment value, select the
time of the ramps, check the latest alarms or access all the settings.
3. Check that the new selected value is within the range of the head specified on the data plate
of the pump unit.
5.2.2 Pre-charging the diaphragm pressure tank
1. Check that the diaphragm pressure tank is completely drained.
2. Pre-charge the diaphragm pressure tank at 0.6 times the pressure value.
5.2.3 Starting the booster set
1. Connect the water supply.
2. Connect the power supply.
3. Check the pre-charge value of the diaphragm pressure tank.
4. Shut the on-off valves located on the delivery line of the pump unit.
5. Prime the booster set (refer to the Installation, Operation and Maintenance Manual of the
pump units in the Smart Pump Range) and the suction manifold.
6. Connect the power supply at the panel switch and set the frequency converter to manual
mode.
7. Start the first pump unit.
8. Open the pump unit delivery on-off valve slowly and bleed the air.
9. Repeat the above operations for the other pump units.
10. Set the frequency converters to automatic mode.