Xylem 2 Pump Booster Sets GXS20, GMD20, GMY20 - Manual (Page 14)

1. Overview
The pressure booster sets, GXS20, GMD20, GMY20 series, are designed to transfer and boost clean
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Operating limits
Fluid temperature: 0°C to +40°C, +60°C depending on the type of pump
Ambient temperature: 0°C to +40°C, +45°C, +50°C depending on the type of pump
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 nPX resistance; level should be raised by
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Maximum inlet pressure: The inlet pressure plus the pressure supplied by the pump against the
closed valve must always be lower than the maximum operating pressure
Starts per hour: Max 60 up to 3 kW, max 40 from 4 kW to  kW, max 30 from 11 kW to
15 kW
WARNING
Limitations to nuid temperature and pressure may be imposed by the membrane
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2. Product Description
The pressure booster set consists of two identical electric pumps connected in parallel and mounted on
a common stand, suction and delivery manifolds, on-off valves, check valves, pressure gauge, pressure
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The system must be equipped with a membrane UBOL The delivery manifold is mUUFE with two couplings
designed for installation of 24-litre tanks with on-off WBMWF Along with the tanks, provide a suitable mani-
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3. Operation
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If the water demand increases, the pressure drops until it reaches the second start value, determining
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GXS20 Single-Phase Version
The single-phase version has a QXS20 control panel:
- Automatic sequential pump regulation with low-pressure control from two pressure switches
- Cyclic changeoveSPGmrst pump to be started
- Changeover lock selector switch
- Delay to prevent simultaneous start-up
- Thermal-magnetic switch for short-circuit protection
- 0Werload protection via a motor protector incorporated in the motor
- Dry running protection via a pressure switch or nPat switch or level sensors with sensitivity adjustment
(accessory electrodes not included)
- Dry running protection cut-in timer
- Shut-down delay timers on both pumps
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