Xylem 2 Pump Booster Sets GXS20, GMD20, GMY20 - Manual (Page 16)

4. Installation
Use suitable equipment to handle the set, avoid impacts, do not use the eyebolts on the motor for lifting
purposes. Before installing the set, make sure it did not suffer any damage during transportation. Install
the pressure booster set in a well-ventilated room, allowing adequate clearance (0.5 m) on all sides and
front for maintenance. The tanks can be mounted on the set or floor. Place the set on a level and sturdy
surface.
Piping
The pipes connected to the set must be adequately sized (if possible, according to manifold diameter).
To prevent undue stress, expansion joints and suitable pipe supports should be provided. You can use
either end of manifold, but don’t forget to plug unused end.
WARNING
The weight of the pipes and tanks increases when they are filled with water.
Before starting the set, make sure you have closed and tightened all the unused
couplings.
Protection Against Dry Running
The electric panels are ready for connection of a float switch or a set of three probe electrodes (suitable
for open tanks) or a minimum pressure switch on the suction side ( recommended value 0.2 - 0.4 bar) .
Refer to the panel wiring diagram for the connections. The triggering of the protection device can be de-
layed by making suitable adjustments on the control panel. When the minimum pressure conditions are
restored, the pumps start up automatically. The protection is not operational in the Manual control mode
and in the selector switch control mode.
WARNING
The sets are supplied with the protection disconnected (factory setting)
Maximum Pressure Protection
Three-phase version only: a pressure switch on the delivery side, connected to the three-phase panel,
can detect any overpressure condition and shut down the pumps in both automatic and manual mode.
Tank Selection
To ensure efficient operation, the set must be connected to a membrane tank. The required water volume
may be distributed among multiple tanks.
Optimum volume is calculated using the following formula
V= Volume in litres
Q= Mean pump capacity in m3/h
P1 = start-up pressure in bar
DP = pressure differential ( P1s-P1) in bar
N = maximum number of starts per hour
Air Feeder
The pressure booster sets with check valves on the suction side are ready for connection of an air feed
device; the coupling for the air pipe is located near the check valve. Certain models of vertical pumps
are provided with an adapter for connection to the drain plug on the base of the pump casing.
Electrical Connections
DANGER
RISK OF
ELECTRIC SHOCK
The electrical connections must be made by a qualified electrician in
accordance with local codes.
Before making the connections, disconnect the power supply!
The wiring diagram and the labels on the panel provide the necessary
information for connection and the required power supply values.
WARNING
Fill the pumps with liquid before starting them. See the pump instructions manual.
Follow the start-up procedure described in section 6.
16
INFORMATION FOR INSTALLERS
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