Motor Cooling; Removing And Fitting The Cable Guard; Splicing The Motor Cable - Grundfos SP Serie Instrucciones De Instalación Y Operación

6.3.5 Installation depth
Make sure that the installation depth of the
pump is always at least 3 ft (1 m) below the
maximum draw-down level of the well. For flow
rates exceeding 100 gpm (22.7 m
performance curves for recommended minimum
submergence.
Never install the pump so that the bottom of the
motor is lower than the top of the well screen or
within five feet of the well bottom.
If the pump is to be installed in a lake, pond,
tank or large diameter well, make sure that the
water velocity passing over the motor is
sufficient to ensure proper motor cooling. The
minimum recommended water flow rates
ensuring proper cooling are listed in section

10.1 Motor cooling

requirements.
6.3.6 Power supply
Check the motor voltage, phase number and
frequency indicated on the motor nameplate
against the actual power supply.
6.3.7 Power cable type
The power cable used between the pump and
control box or control panel must be approved
for submersible pump applications. Conductors
may be solid or stranded. The cable may consist
of individually insulated conductors twisted
together, insulated conductors molded side by
side in one flat cable or insulated conductors
with a round overall jacket.
The conductor insulation must be type RW,
RUW, TW, TWU or equivalent and must be
suitable for use with submersible pumps. An
equivalent Canadian Standards Association
(CSA) certified cable may also be used. See
section 10.4 Submersible drop cable selection
charts (60 Hz) for recommended cable lengths.
6.4 Removing and fitting the cable
guard
If the cable guard is attached with screws,
remove the screws to loosen the cable guard. To
fit the cable guard on the pump, tighten the
screws to fit the cable guard securely to the
pump.
CAUTION
Caution
When the cable guard has been fitted,
make sure that the pump chambers
are aligned.

6.5 Splicing the motor cable

Note
3
/h), refer to
If the splice is carefully made, it will work as well
as any other portion of the cable, and will be
completely watertight. Grundfos recommends
that you use a heat shrink splice kit. Make the
splice in accordance with the kit manufacturer's
instructions. Typically a heat shrink splice can
be made as follows:
1. Examine the motor cable and the
submersible drop cable carefully for damage.
2. Cut the motor leads off in a staggered
manner. Cut the ends of the drop cable so
that the ends match up with the motor leads.
See fig. 6. On single-phase motors, be sure
to match the colors.
3. Strip back and trim off 1/2 inch of insulation
from each lead, making sure to scrape the
wire bare to obtain a good connection. Be
careful not to damage the copper conductor
when stripping off the insulation.
4. Slide the heat shrink tubing on to each lead.
Insert a properly sized "Sta-Kon" type
connector on each lead, making sure that
lead colors are matched. Using "Sta-Kon"
crimping pliers, indent the lugs. See fig. 7.
Be sure to squeeze hard on the pliers,
particularly in the case of a large cable.
5. Center the heat shrink tubing over the
connector. Using a propane torch, lighter, or
electric heat gun, uniformly heat the tubing
starting first in the center working towards
the ends. See fig. 8.
6. Continue to apply the heat to the tubing
taking care not to let the flame directly
contact the tubing. When the tubing shrinks
and the sealant flows from the ends of the
tubing, the splice is complete. See fig. 9.
A good cable splice is critical to
proper operation of the submersible
pump and must be done with extreme
care.
11