Splicing The Motor Cable - Grundfos SP Series Installation And Operating Instructions Manual

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Fig. 3 Motor position during filling – MMS
3.2.5 Installation depth
A check should be made to ensure that the
installation depth of the pump will always be at
least (5) five to (10) ten feet (1.5 to 3 m) below
the maximum draw-down level of the well. For
flow rates exceeding 100 gpm (22.7 m
to performance curves for recommended
minimum submergence.
The bottom of the motor should never be installed
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, the water velocity passing
over the motor must be sufficient to ensure
proper motor cooling. The minimum
recommended water flow rates which ensure
proper cooling are listed in section 7.1 Minimum
water flow requirements for submersible pump
motors on p. 19.
3.2.6 Electrical supply
The motor voltage, phase and frequency
indicated on the motor nameplate should be
checked against the actual electrical supply.
3.2.7 Wire cable type
The wire cable used between the pump and
control box or panel should be approved for
submersible pump applications. The conductor
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 should be type RW,
RUW, TW, TWU or equivalent and must be
suitable for use with submersible pumps. An
equivalent Canadian Standards Association
certified wire may also be used. See section
7.4 Submersible pump cable selection chart (60
Hz) on p. 21 for recommended sizes of cable
lengths.
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3.3 Splicing the motor cable

Note
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
using a heat shrink splice kit. The splice should
be made in accordance with the kit
manufacturer's instructions. Typically a heat
shrink splice can be made as follows:
45°
1. Examine the motor cable and the 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. 4.
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
3
/h), refer
connector on each lead, making sure that lead
colors are matched. Using a "Sta-kon"
crimping pliers, indent the lugs; see fig. 5. Be
sure to squeeze hard on the pliers, particularly
when using 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. 6.
6. Continue to apply the heat to the tubing using
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. 7.
Fig. 4
A good cable splice is critical to
proper operation of the submersible
pump and must be done with
extreme care.
Cutting and stripping the motor leads