Grundfos SP Series Installation And Operating Instructions Manual page 10

The ground wire should be a bare copper
conductor at least the same size as the drop
cable wire size.
The ground wire should be run as short a
distance as possible and be securely fastened to
a true grounding point.
True grounding points are considered to be:
• a grounding rod driven into the water strata
• steel well casing submerged into the water
lower than the pump setting level
• steel discharge pipes without insulating
couplings.
If plastic discharge pipe and well casing are used
or if a grounding wire is required by local codes, a
properly sized bare copper wire should be
connected to a stud on the motor and run to the
control panel.
Warning
Do not ground to a gas supply line.
Connect the grounding wire to the
ground point first and then to the
terminal in the control box or panel.
Electrical
disconnect
Electricity supply
Control
Fig. 13 Wiring and installation diagram
3.5.5 Wiring checks and installation
Before making the final surface wiring connection
of the drop cable to the control box or panel, it is
a good practice to check the insulation resistance
to ensure that the cable and splice are good.
Measurements for a new installation must be at
least 2,000,000 ohm. Do not start the pump if
the measurement is less than this.
If it is higher than 2,000,000 ohm, the drop cable
should then be run through the well seal by
means of a conduit connector in such a way as to
eliminate any possibility of foreign matter
entering the well casing.
10
box
box
Conduit
connector
Submersible
cable
Pressure
gauge
Pressure
switch
Pressure
tank
Well
seal
Tape
Pump
Motor
Conduit should always be used from the pump to
the control box or panel to protect the drop cable;
see fig. 13.
Finish wiring and verify that all electrical
connections are made in accordance with the
wiring diagram.
Check to ensure the control box or panel and
high voltage surge arrester have been grounded.
House
supply