Xylem GHV - Manual (Page 12)

12
1. Overview
The Lowara pressure booster sets of the GHV, GV, GHC series are designed to transfer and boost clean
water pressure in water systems for homes, offices, communities and industry.
Operating limits
Fluid temperature :
0°C to +80 °C
Ambient temperature:
0°C to + 40 °C
Operating pressure:
Max 8 bar, 10 bar, 16 bar depending on the type of pump (see instruc-
tions handbook)
Minimum inlet pressure:
According to NPSH curve and flow resistance; level should be raised by
a safety margin of at least 0.5 metres if water contains air.
Maximum inlet pressure:
The inlet pressure plus the pressure supplied by the pump against the clo-
sed valve must always be lower than the maximum operating pressure.
Starts per hour:
Do not exceed the number of starts per hour indicated in section 12.
Limitations to fluid temperature and pressure may be imposed by the membrane
tank. Observe the operating limits!
2. Product Description
The pressure booster set consists of identical electric pumps connected in parallel and mounted on a
common stand, suction and delivery manifolds, on-off valves, check valves, pressure gauge, pressure
transmitters, frequency converters and a Single-phase or Three-phase control panel.
The system must be equipped with a membrane tank. The delivery manifold is fitted with couplings desi-
gned for installation of 24-litre tanks with on-off valve. Along with the tanks, provide a suitable manifold
support. Additional floor-standing tanks may be installed and connected to the manifold.
3. Operation
The pumps are controlled by the converters according to system requirements.
The membrane tank provides for initial water demand.
When the pressure drops to the control value, the first variable speed pump starts running.
If the water demand rises, the speed increases until the subsequent pumps also start.
If the demand drops, the speed decreases until the pumps stop.
If the demand drops further, the last pump fills the tank and then shuts down.
GHV/…../M, GHC/…../M Single-Phase Version
The single-phase version has a single-phase control panel, the frequency converters power the motors
with variable frequency three-phase voltage.
Automatic line protection circuit breakers are installed on the control panel for each frequency converter.
GHV, GVE, GVF, GHC Three-Phase Version
The three-phase version has a three-phase control panel, the frequency converters power the motors
with variable frequency three-phase voltage.
On the control panel are installed automatic line protection circuit breakers for each frequency converter,
as well as a main switch.
WARNING
en