Lorentz PS200 Instructions For Installation Operation Service page 66

Glossary of Solar Electricity and Water Pumping continued
Well Seal - Top plate of a well casing that
provides a sanitary seal and support for the
drop pipe and pump. Alternative: See pitless
adapter
Water Well Characteristics
Driller's Log - The document on which well
characteristics are recorded by the well driller.
In most states, drillers are required to register
all water wells and to send a copy of the log to
a state office. This supplies hydrological data
and well performance test results to the well
owner and the public. Synonym: well record.
Drawdown - Lowering of level of water in a
well due to pumping.
Drawdown level - Depth to the water
surface in a well while it is being pumped.
Recovery Rate - Rate at which groundwater
refills the casing after the level is drawn down.
This is the term used to specify the production
rate of the well.
Static Water Level - Depth to the water
surface in a well under static conditions (not
being pumped). May be subject to seasonal
changes or lowering due to depletion.
Wellhead - Top of the well.
Pump System Engineering
Friction Loss - The loss of pressure due to
flow of water in pipe. This is determined by 4
factors: pipe size (inside diameter), pipe
material, flow rate, and length of pipe. It is
determined by consulting a friction loss chart
available in an engineering reference book or
from a pipe supplier. It is expressed in PSI or
Feet (equivalent additional feet of pumping).
Pipe fittings, especially 90° elbows, impose
additional friction.
Head - See synonym: vertical lift.
Suction Lift - Applied to surface pumps:
Vertical distance from the surface of the water
in the source, to a pump located above the
surface. This distance is limited by physics to
around 20 feet at sea level (subtract 1 ft. per
1000 ft. altitude) and should be minimized for
best results.
Submergence - Applied to submersible
pumps: Distance below the static water level,
at which a pump is set.
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Total Dynamic Head - vertical lift + friction
loss in piping (see vertical lift and friction
loss).
Vertical Lift - The vertical distance that
water is pumped. This determines the
pressure that the pump pushes against. Total
vertical lift = vertical lift from surface of water
source up to the discharge in the tank + (in a
pressure system) discharge pressure.
Synonym: static head. Note: Horizontal
distance does NOT add to the vertical lift,
except in terms of pipe friction loss. NOR
does the volume (weight) of water contained
in pipe or tank. Submergence of the pump
does NOT add to the vertical lift. See total
dynamic head.
Water Distribution
Cut-In Pressure and Cut-Out Pressure -
See pressure switch.
Gravity Flow - The use of gravity to produce
pressure and water flow. A storage tank is
elevated above the point of use, so that water
will flow with no further pumping required. A
booster pump may be used to increase
pressure. 2.31 vertical feet = 1 PSI. 10
vertical meters = 1 bar. See pressure.
Head - Seevertical lift and total dynamic
head. In water distribution, synonym: vertical
drop. See pressure.
Open Discharge - The filling of a water
vessel that is not sealed to hold pressure.
Examples: storage (holding) tank, pond, flood
irrigation. Contrast: pressure tank.
Pressure - The amount of force applied by
water that is either forced by a pump, or by
the gravity. Measured in pounds per square
inch (PSI) or bar (atmospheres).
vertical lift (or drop) in Feet / 2.31. Metric: 1
Bar = vertical lift (or drop) of 10 vertical
meters.
Pressure Switch - An electrical switch
actuated by the pressure in a pressure tank.
When the pressure drops to a low set-point
(cut-in) it turns a pump on. At a high point
(cut-out) it turns the pump off.
Pressure Tank - A fully enclosed tank with
an air space inside. As water is forced in, the
air compresses. The stored water may be
released after the pump has stopped. Most
pressure tanks contain a rubber bladder to
capture the air. If so, synonym: captive air
tank.
PSI =