Section 3: Installation And Setup; General Installation Guidelines; Proper Grounding; Corrosive Water And Ground - Pentair Pentek Series Electronic Manual

SECTION 3: Installation and Setup

3.1

General Installation Guidelines

• In order to avoid abrasion to the power and control
cables, pad the top of the well casing (a rubber pad is
recommended) where the cable will pass over it; use
a cable reel for cable control.
• The unit must always be easy to rotate in the
hoisting gear.
• Lay power and control cables out straight on the
ground (no loops) before installation. Guide cables
during lowering so that they are not stretched or
squeezed while pump is being installed. Make sure
that cable insulation is not nicked or damaged before
or during installation. Never use the electrical cables
to move the motor/pump.
• The pump and motor are heavy. Make sure that all
connections are secure and that the hoisting gear is
adequate to do the job before starting to lift pump.
Don't stand under the unit. Don't allow extra people
into the area while hoisting the unit.
• If motor or pump/motor unit are attached to a
supporting girder, do not remove girder until unit
is vertical.
• Install pump at least 10' (3m) below the lowest water
level during pumping, but at least 6' (2m) above the
bottom of the well.
• 6" motors can be operated in vertical or horizontal
(when lead wire is at 12:00 position facing motor
flange) positions.
• 4" motors can be operated in vertical or horizontal
positions. Note that the thrust bearing will have
shorter life in a non-vertical application. In such an
installation, keep frequency of starts to less than
10 per day.
3.2

Proper Grounding

Hazardous voltage. Can shock, burn
or cause death. Installation or service to electrical
equipment should only be done by qualified electrician.
Control panels must be connected to supply ground
Proper grounding serves two main purposes:
1. It provides a path to ground in case of a ground-fault.
Otherwise the current would present a shock or
electrocution hazard.
2. It protects equipment from electrical surges.
Use wire the same size as, or larger than motor's
current-carrying wires (consult Tables in the motor
section).
Installations must comply with the National Electric Code
as well as state and local codes.
All systems must have lightning (surge) protection with a
secure connection to ground.
An above ground lighting (surge) protection must be
grounded metal-to-metal and extend all the way to
the water bearing layer to be effective. Do not ground
the lightning (surge) protection to the supply ground
or to a ground rod as this will provide little or no surge
protection to the unit.
All motors are internally grounded and requires a 3 or
4-wire drop cable.
3.3

Corrosive Water and Ground

Some waters are corrosive, and can eventually corrode
the ground wire. If the installation uses a metal well
casing, any ground current will flow through it. In the
case of plastic piping and casing, the water column would
carry the current in a ground fault situation.
To prevent this, route the motor ground wire and the
motor power leads through a GFCI with a 10 mA set
point. In this way, the GFCI will trip when a ground fault
has occurred AND the motor ground wire is no longer
functional.
3.4

Check Valves

Check valve installation is necessary for proper pump
operation. The pump should have a check valve on its
discharge, or within 25 feet (7.62 m) of the pump. For very
deep wells, locate a check valve at least every 200 feet
(61 m) vertical.
• Use only spring type or gravity-poppet check
valves. Swing type valves can cause water hammer
problems.
• Do not use drain-back style check valves (drilled).
Check valves serve the following purposes:
• Maintain Pressure: Without a check valve, the pump
has to start each cycle at zero head, and fill the drop
pipe. This creates upthrust in the motor, and would
eventually damage both the pump and motor.
• Prevent Water Hammer: If two check valves are used,
and the lower one leaks, then a partial vacuum forms
in the pipe. When the pump next starts, the flow fills
the void area quickly, and creates a shock wave that
can break piping and damage the pump. If you get
water hammer on pump start, this may be the cause.
• Prevent Back-Spin: Without a functioning check
valve, upon shutoff, the water drains back through
the pump, and cause it to rotate backwards. This can
create excessive wear on the thrust bearing, and if the
pump restarts as water is flowing down the pipe, it
will put an excessive load on the system.
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