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3) ELECTRICAL CONNECTIONS
3) ELECTRICAL CONNECTIONS
The installer is responsible for making electrical connections
to the mains supply in compliance with relevant local
regulations. Ensure that a professional electrician carries out
the electrical connections and that the following guidelines
are followed:-
Ÿ
All installations must be provided with an isolator to cut off mains power
supply and coarse current protection in the form of a fuse or MCB rated
at 2-3 times the full load current as given on the pump plate.
Ÿ
Ensure that the power supply rating complies with the specification on
the pump rating plate.
Ÿ
Electrical connections must be made according to details in the pump
junction box cover and effective earthing must be provided according to
local regulations.
Ÿ
Single-phase motors are protected against overloads by a thermal
overload fitted in the motor windings. Three phase motors should be
installed with remote starter.
WARNING
!
If there is negative suction (i.e the pump is above the suction water level)
the suction pipe must be slightly angled upwards towards the pump inlet
to avoid the formation of air locks. It must also be immersed in water by
at least 0.5m to avoid the formation of vortexes and a good quality foot
valve must be fitted.
!
Ensure that all suction pipe connection are completely airtight or else the
pump will not operate.
!
The diameter of the delivery pipe must be chosen to suit the flow rate and
pressure required at the delivery point though must not be smaller than
the pump outlet size. It is also advisable to fit a non-return valve and
isolating valve on the delivery outlet.
!
This measure is essential if the delivery pressure exceeds 20 meters.
!
The pipes must be fitted using suitable brackets to avoid transmitting
stress to the pump body. Take care not to cause damage by over
tightening the pipes during fitting.
