English
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WILO AG 10/2006
7.2 Hydraulic connection
• The installation and connection dimensions are
given in fig. 3.
-
Pump with two bolt oval flanges: Pipe is
threaded (NPT) directly into the companion
flanges supplied with the pump.
-
Pump with round 300 lb flange have accessory
companion flagnes (counter flanges) that attach
to system piping in a manner dependant on the
flange type (threaded NPT, weld neck etc.).
• When fitting the oval flange, only the bolts supplied
should be used. The use of longer bolts might dam-
age the base of the pump.
• The fluid flow direction is indicated on the pump
body.
• Pump must be installed in such a way that it is not
stressed by the pipework. The pipes must be
attached so that the pump does not bear their
weight.
• It is recommended that isolation valves be installed
on the suction and discharge side of the pump. This
will save having to drain and refill the system if the
pump needs replacing.
• It is recommended that the pipe leading into the
suction side of the pump has a minimum length
which is three times as long as the pipe diameter.
• A check valve should be placed on the discharge pipe
to protect it from water hammer.
• Note: To pump water with a large content of air or
hot water, we recommend installing the by-pass kit.
Fig. 2: Flooded or pressurized suction applications
• For direct connection to a public drinking water sys-
tem please refer to local plumbing codes for the
requirement of a back flow protection device.
• For indirect connection via a tank, the suction pipe
must have a strainer, to keep any impurities out of
the pump.
Fig. 1: Suction lift applications
• To avoid any loss of head, use the shortest possible
suction pipe and keep it free of bends that would
increase the piping friction losses.
• Connections have to be correctly sealed: No air
entrance is allowed on the suction pipe (2 %). See
figure 1
7.3 Electrical connection
• The electrical characteristics (frequency, voltage,
nominal current) of the motor are mentioned on the
name plate: check if it complies with the mains sup-
ply used.
• The pump must be connected to the power supply
by a solid cable equipped with a grounded plug-con-
nection or a main power switch.
• Three-Phase motors must be connected to an
approved motor starter. The set nominal current of
which must correspond to the electrical data on the
pump name plate
• The supply cable must be laid so that it never
touches the pipe work and/or the pump and motor
casing.
CAUTION! Possible damage of the pump caused
by cavitation (boiling water at the eye of the first
impeller
Do not install in a suction lift position with fluids
above 175 deg F (80 Deg C). Please refer to the
chart below for NPSH required corrections for
suction lift applications above sea level.
Altitude
Loss of head
0 ft
0.0 ft
1000 ft
1.2 ft
2000 ft
2.4 ft
3000 ft
3.5 ft
5000 ft
5.7 ft
7000 ft
7.6 ft
10000 ft
10.7 ft
Temperature
Loss of suction head (HA)
Temperature
Loss of suction head (HA)
20 °C
0.20 mCL
70 °F
0.70 ft
30 °C
0.40 mCL
90 °F
1.50 ft
40 °C
0.70 mCL
100 °F
2.00 ft
50 °C
1.20 mCL
120 °F
3.70 ft
60 °C
1.90 mCL
140 °F
5.70 ft
70 °C
3.10 mCL
160 °F
10.10 ft
80 °C
4.70 mCL
180 °F
16.20 ft
90 °C
7.10 mCL
200 °F
26.20 ft
100 °C
10.30 mCL
210 °F
32.60 ft
WARNING! Electrical shock hazard
Dangers caused by electrical energy must be
excluded.
• Electrical work by a qualified electrician only!
• National Electrical Codes, local codes and regula-
tions must be strictly followed.
• All electrical connections must be performed
after the electrical supply has been switched off
and secured against unauthorized switching.
• For safe installation and operation a proper
grounding of the pump to the power supply’s
grounding terminals is required.
