Water feed
Depending on the availability of water and pipework, the pump
’s wheel can be driven in one of three ways:
1
– Water supply at top
This is the best way to drive the wheel. The delivery pipe must be centralised
with the top of the wheel no more than 10cm above the drive vanes. The delivery
of water will determine the rotation of the wheel.
2
– Water supply at lower level
In situations where it is not possible to provide a water supply to the top of the
wheel, it is possible to direct the jet at the spokes of the wheel and drive it in
that fashion. Where this methodology is required, it is essential to utilise a larger
wheel in order to optimise the water pressure available.
3
– Water supply at ground level
When topographic conditions do not permit installation of the feed water tube
in the normal way, a suitable culvert should be constructed either from brick or
wood. This should be approximately the same width as the paddles on the wheel,
in order to optimise the water pressure available. This method of propulsion
is not very efficient and a typical rotation speed is 8
–12 r.p.m. should be
anticipated. To increase efficiency, multiple streams can be fed into the culvert to
increase feed water volume and thereby, pressure.
Wheels should be specified for specific water feed applications and preferably
only after a survey of the water availability has been undertaken.
Suction System
Notes
• The maximum vertical lift in water head possible with ZM–MAXXI pumps is
approximately 7m. Horizontally, the suction distance is approximately 60m.
For installations exceeding 2m vertically, or a horizontal distance more than
5m, a non return valve should be installed at the foot of the pump.
• Pumps should always be primed with water before use, when point of suction
is more than 2m from pump.
• As a rule, 1m of vertical water lift is equivalent to 10m horizontal pumping
• Water quality will affect the pump’s leather seals and mechanism. Where sand
and other gritty substances are carried in the water flow, the life of the pump
could be adversely effected. This additional wear and tear is not covered by
the
unit’s guarantee.
NB! Gap between paddles and base
must not be less than 50mm
