Xylem e-NSCS: 4 Installation

en - Translation of the original instructions

The following equation is used to calculate the maximum height above

4 Installation

the liquid level which the pump can be installed:

(p

b

*10.2 - Z) ≥ NPSH + H

f

+ H

v

+ 0.5

Precautions

p

b

Barometric pressure in bar (in closed system is system pres-

WARNING:

sure)

• Observe accident prevention regulations in force.

NPSH Value in meter of the pump intrinsic flow resistance

• Use suitable equipment and protection.

H

f

Total losses in meters caused by passage of liquid in the suc-

• Always refer to the local and/or national regulations,

tion pipe of the pump

legislation, and codes in force regarding the selection of

the installation site, plumbing, and power connections.

H

v

Steam pressure in meters that correspond to the temperature

of the liquid T °C

Electrical Hazard:

0.5 Recommended safety margin (m)

• Make sure that all connections are performed by quali-

Z Maximum height at which the pump can be installed (m)

fied installation technicians and in compliance with the

regulations in force.

For more information, see Figure 13 .

• Before starting work on the unit, make sure that the unit

(p

b

*10.2 - Z) must always be a positive number.

and the control panel are isolated from the power sup-

ply and cannot be energized. This applies to the control

NOTICE:

circuit as well.

Do not exceed the pumps suction capacity as this could cause cavita-

tion and damage the pump.

Grounding (earthing)

4.1.2 Piping requirements

Electrical Hazard:

• Always connect the external protection conductor to

Precautions

ground (earth) terminal before making other electrical

connections.

WARNING:

• You must ground (earth) all electrical equipment. This

• Use pipes suited to the maximum working pressure of

applies to the pump equipment, the driver, and any

the pump. Failure to do so can cause the system to

monitoring equipment. Test the ground (earth) lead to

rupture, with the risk of injury.

verify that it is connected correctly.

• Make sure that all connections are performed by quali-

• If the motor cable is jerked loose by mistake, the

fied installation technicians and in compliance with the

ground (earth) conductor should be the last conductor

regulations in force.

to come loose from its terminal. Make sure that the

ground (earth) conductor is longer than the phase con-

NOTICE:

ductors. This applies to both ends of the motor cable.

• Add additional protection against lethal shock. Install a

Observe all regulations issued by authorities having jurisdiction and by

high-sensitivity differential switch (30 mA) [residual cur-

companies managing the public water supplies if the pump is connect-

rent device RCD].

ed to a public water system. If required, install appropriate backflow-

prevention device on the suction side.

4.1 Facility requirements

Piping checklist

4.1.1 Pump location

Check that the following requirements are met:

• All piping is independently supported, piping must not place a bur-

DANGER:

den on the unit.

Do not use this unit in environments that may contain flam-

• Flexible pipes or unions are used, in order to avoid transmission

mable/explosive or chemically aggressive gases or powders.

of pump vibrations to the pipes and vice versa.

• Use wide bends, avoid using elbows which cause excessive flow

Guidelines

resistance.

Observe the following guidelines regarding the location of the product:

• The suction piping is perfectly sealed and airtight.

• If the pump is used in an open circuit, then the diameter of the

• Make sure that no obstructions hinder the normal flow of the cool-

suction pipe is suited to the installation conditions. The suction

ing air that is delivered by the motor fan.

pipe must not be smaller than the diameter of the suction port.

• Make sure that the installation area is protected from any fluid

• If the suction piping must be larger than the suction side of the

leaks, or flooding.

pump, then an eccentric pipe reducer is installed.

• If possible, place the pump slightly higher than the floor level.

• If the pump is placed above liquid level, a foot valve is installed at

• The ambient temperature must be between 0°C (+32°F) and

the end of the suction piping.

+40°C (+104°F).

• The foot valve is fully immersed into the liquid so that air cannot

• The relative humidity of the ambient air must be less than 50% at

enter through the suction vortex, when the liquid is at the mini-

+40°C (+104°F).

mum level and the pump is installed above the liquid source.

• Contact the Sales and Service Department if:

• Appropriately sized on-off valves are installed on the suction pip-

• The relative air humidity conditions exceed the guidelines.

ing and on the delivery piping (downstream to the check valve) for

• The room temperature exceeds +40°C (+104°F).

regulation of the pump capacity, for pump inspection, and for

• The unit is located more than 1000 m (3000 ft) above the

maintenance.

sea level. The motor performance may need to be de-rated

• Appropriately sized on-off valve is installed on the delivery piping

or replaced with a more powerful motor.

(downstream to the check valve) for regulation of the pump ca-

For information about which value to de-rate the motor with, see Table

pacity, for pump inspection, and for maintenance.

12 .

• In order to prevent back flow into the pump when pump is turned

off a check valve is installed on the delivery piping.

Pump positions and clearance

WARNING:

Provide adequate light and clearance around the pump. Make sure

that it is easily accessible for installation and maintenance operations.

Do not use the on-off valve on the discharge side in the

closed position in order to throttle the pump for more than a

Installation above liquid source (suction lift)

few seconds. If the pump must operate with the discharge

side closed for more than a few seconds, a bypass circuit

The theoretical maximum suction height of any pump is 10.33m. In

must be installed to prevent overheating of the liquid inside

practice, the following affect the suction capacity of the pump:

the pump.

• Temperature of the liquid

• Elevation above the sea level (in an open system)

For illustrations that show the piping requirements, see Figure 14 and

• System pressure (in a closed system)

Figure 15 .

• Resistance of the pipes

• Own intrinsic flow resistance of the pump

• Height differences

e-nscs Installation, Operation, and Maintenance Manual 15