Sun Pumps MTR BLM-SB-103S-120Y - Manual (Page 5)

wire size, conduit runs, trenching, controller accessibility, tank location, pump head etc. Shading even a
small portion of the array can reduce the output of the entire array and thus reduce or completely stop the
output of the pump. There is no substitute for a good plan!
The PCC-series controller can either be mounted indoors or outdoors. Locate all system equipment as
close as possible to each other. For top of pole mount racks, the controller is usually mounted on the north
side (shaded side) of the mounting pole. The controller must be mounted in a vertical position for proper
cooling and to keep the electronics dry. The pole should be located close to the well (bore hole). This
general physical layout is conducive to clean installation both aesthetically and electrically.
3.2 System Design Basics (Read carefully before installation)
1. The pump discharge piping should be sized for efficient pump operation. We suggest using the
Friction Loss Tables to calculate the Total Dynamic Head using different pipe sizes. As a rule of
thumb use 1” for up to 8 GPM, 1 ¼” for up to 25 GPM, 1 ½” for up to 40 GPM and 2” for up to
70 GPM.
2.
For optimum pump performance make sure that the wire is sized properly for the length of run
between the pump and the solar modules. Wire sized too small will cause a decreased output
from the pump. Keep the distance from the solar modules to the pump as short as possible.
Refer to a DC wire loss chart for proper sizing. It is recommended to keep the voltage drop
under 3%.
3. Due to the aggressive action of DC power, it is essential that any under-water splice be made
correctly. This splice must be watertight. Improper sealing of the splice will cause poor pump
performance and may cause damage to the system. A submersible 4 wire splice kit is
recommended for this watertight connection.
4. Never rest the pump on the bottom of the well (bore hole). This can cause the pump to fill with
mud and damage the impellers. It is recommended that the pump be set at least 10 feet off of the
bottom of the bore hole. If this is not possible the pump may be placed a minimum of 5 feet above
the bottom of the well. If possible, install the pump above the well casing perforations. This will
allow any sand intrusion to settle below the pump.
5. Never install a pump in a well that has had an oil-lubricated line shaft turbine in it without
cleaning it first. Any drip oil remaining in the water may damage the pump shaft bearing
sleeves.
6. On deep wells, a check valve should be installed in the drop pipe every 200 feet.
7. Never install the controller in direct sunlight. Direct sunlight on the controller may cause over-
heating of the controller.
8. Never lay the controller on the ground or mount the controller in a horizontal position. The
controller should be mounted in a vertical position only. A convenient place to mount the
controller is on the north side (shaded side) of the solar module array.
9. The controller should be grounded to the pump motor housing, the frame of the solar modules
and to an 8-foot ground rod. If the well casing is steel it may be used as the ground rod. Drill
and tap a hole in the casing or weld a bolt to the casing for the ground lug. Use only a copper
lug to attach the ground wire. The cemented support structure pole will not provide an adequate
ground. Do not ground the positive or negative electrical wires. Always use a DC
surge/lightning arrestor on the panel side of the controller. (Midnight Solar MN-SPD surge
arrestor is recommended)
10. Do not ground the array positive or negative electrical wires.
3.3 Well Measurements
Before installing the pump measure the depth of the well (bore hole) and static water level. The static
water level is the distance from the top of the well casing to the water level in the well (bore hole). This
information is necessary in determining the pump setting (See Figure 1).