STICHTING BAKENS VERZET
1018 AM AMSTERDAM,
THE NETHERLANDS
Director,
T.E.(Terry)
Manning,
Schoener 50,
1771 ED
Wieringerwerf,
The Netherlands.
Tel:
0031-227-604128
Homepage:
http://www.flowman.nl
E-mail:
(nameatendofline)@xs4all.nl : bakensverzet
MODEL FOR SUSTAINABLE SELF-FINANCING INTEGRATED
RURAL AND POOR URBAN DEVELOPMENT FOR THE WORLD'S POOR
Incorporating
innovative social, financial, economic, local administrative and productive
structures, numerous renewable energy applications, with an important role for
women in poverty alleviation in rural and poor urban environments.
"Money is not
the key that opens the gates of the market but the bolt that bars them"
Gesell, Silvio The
Natural Economic Order
Revised English
edition, Peter Owen, London 1958, page 228
Edition 9: 07
December,2006
SOLAR SPRING : MAINTENANCE
How the Sunprimer controller works.
With panels coupled with each other and to the controller and the controller is connected to the pump motor, in the first instance
a) All transistors are initially in the OFF position
b) The pump motor has not received any impulses from the panels.
The 22000 uF capacitor starts charging via the brown cable and via the 3300 Ohm 4W resistor. After about 3 minutes (Mk I/d and Mk I/s controllers) and 2 minutes (Mk II controller), the capacitor voltage overtakes the DB3 Diac limit (nearly 30V) or, according to the SW1 on-off condition, the DB3 Diac limit plus 27V Zener limit (57-60V), and the BTA thyristor switches on and the 22000uF capacitor transmits current surge to the pump motor. Through the 8200 ohm 2W resistor (Sunprimer Mk I) or the 5600 ohm 2W resistor plus the 3300 resistor (Sunprimer Mk I/b), the output voltage switches the BDX53C Q4 and the BDX88C Q2 transistors on. The pump is then connected to the solar panels and starts working. The BTA16 thyristor subsequently switches off due to the low current from the 3300 ohm 4W resistor.
When output voltage is not greater than a given threshold (currently 20-21V) in which case the pump is turning slowly or not at all because the power from the panels is lower than the pump load, the BDX53C Q4 and BDX88C Q2 resistors are insufficiently polarised, and in off mode, cutting the contact to the pump motor. With arrays of 4 solar modules, the BDX53C Q3 and BDX88C Q1 transistors normally connect all four panels in series, as the voltage from the modules keeps the transistors on via the 6800 ohm resistor.
If output voltage is lower than a given threshold (currently 30-32V) transistors BDX53C Q3 and BDX88C Q1 are inadequately polarised, and are switched off so that the modules are then connected in parallel. A pulse PUT 2N6028 tries two or three times a second to switch the transistors on again. If the voltage is high enough, contact is switched to series mode. If voltage is not high enough, the modules are connected in parallel. The remote switch supplied with the Sunprimer MkI/b, when closed, cuts out Q2 and Q4 polarisation, and discharges the 22000 uF capacitor.
Maintenance of the Sunprimer Controller : How the Sunprimer works (cont.)
Both four-panel and two-panel configurations supply current directly from the panels to the pump without conversion. The black and the blue wires on the four panels configuration make automatic series/parallel connections in accordance with the available voltage. With four panels in a two-panel configuration, the automatic series/parallel switching feature is lost, and only a connection in series is possible so the pump might only start in good sunlight. If the internal 2 panel/4 panel switch is incorrectly used, the best capacitor charging voltage is therefore not attained. A traditional continuous DC/DC converter is better than the simple "2 gear" converter used for the Sunprimer units, but in practice the daily differences are very small. Since other controller functions for the Solar Spring pump are more complex than those designed for other controllers, the introduction of a DC/DC converter with the Sunprimer has been deferred.
A present limitation of the present series/parallel switching device is that it does not work well if the two pairs of panels are not equal or do not receive the same insolation.
IT IS EXTREMELY IMPORTANT to use low resistance (max 1.5 ohm) cables as prescribed in the instructions the better to handle higher heads according to cam size with a load of less than 4.5 amps. To avoid current peaks, water pipes should not be closed off with valves or taps. Since motor resistance is about 1.8 ohms, the motor is then protected. The D11 diode is used to protect the BDX88C Q2 transistor from (infrequent) inverse voltage. This Darlington type transistor has a built-in inverse protection diode which has in one or two situations proved to be too weak to handle irregular sudden interruptions. It is nearly impossible to check MkI controllers by connecting them to DC generators instead of to solar panels as the MKI controllers DO NOTE HAVE A COMMON GROUND (there are two independent fluctuating grounds). It is, however, possible to check 99% of controller failures without connecting them to any panels or DC generators, or by connecting them to a simple unstabilised DC generator comprising
For more information refer to: Functions of Sunprimer controller
Menu for the maintenance of Solar Spring pumps.
Main menu Solar Spring pumps.
Some recommended technologies,
List of attachments to the Model.
Complete index of the Model.
Model Homepage.
Typical list of graphs and
drawings.
List of abbreviations used.
List of key words.
Documents for funding
applications.
Homepage Bakens Verzet