final report of internship EWB Rwanda Mukindo water project by Ntambara Sylvestre Owen Berbason

Controller Installation
General
The pump system must be equipped with a proper sized DC disconnect switch. The switch must
be installed between the solar generator and controller. It must meet the following
requirements:
‣ minimum 850 V DC
‣ continuous current rating according to maximum current of pump controller or higher
‣ the switch must be rated for DC current, NOT AC
Electrical conduit is recommended
We recommend the use of an electrical conduit (pipe) to protect outdoor wiring from the
weather, from human activities and from chewing animals. If you do not use a conduit, use a
strong, high-quality outdoor cable. Where cables enter the junction box, install sealed strainrelief
cable glands.
Treat the controller as industrial waste when processing the discarded controller. It is possible
that some components could produce toxic and harmful gas.
Controller Placement
The controller must be protected from water, moisture and animals. Place the controller in a dry
and sufficiently ventilated environment.
Place the controller close to the solar array, not the pump. This will reduce the risk of lightning
damage. Explanation: The controller’s input circuitry is more sensitive to surges than its output.
It is safest to minimize the length of the input wiring.
Electronic devices are most reliable when they are protected from heat. Mount the controller
where it is shaded from the midday sun. An ideal location is directly under the solar array, on the
North side of the mounting structure. If no shade is available, cut a piece of sheet metal and bolt
it behind the top of the controller. Bend it over the controller to provide shade. This is especially
important in extremely hot locations. Extreme heat may trigger a thermal function in the
controller causing it to reduce the power consumption or turn it off.
Figure 2: Controller dimensions for installation