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 About Bakens Verzet




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



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 12: 04 December,2006

Specifications of pump

Pump type

Submersible coaxial horizontal piston

Nominal depth

0-150m (within normal materials stresses)

Maximum depth

250 + m

Nominal installation below water level

2-10m.Where less than 1m. consult supplier

Maximum installation below water level

50 + m with panel & controller, 25m. with batteries at 24V

Pump height


Pump diameter


Number of units in 6" ID borehole

Up to 5

Piston diameter

2 x 40mm

Pump lubrication

40Ml of non toxic oil

Pump weight with motor


Pump weight without motor


Outlet, internal diameter


Valve type

2 x conical flapper

Diameter valves

60mm external

Cam diameters in mm

2.0; 2.2; 2.6; 3.0

Piston movement acc/to cam size in mm

1.0; 1.1; 1.3; 1.5

Piston diameter

2 x 40mm

Standard cam size

2.6mm (3.0mm with Hyboost)

Standard spring force


Maximum hydraulic capacity

27 litres/minute with Hyboost;16 litres/minute without Hyboost

Hyboost pipe (standard)


Specifications of motor

Motor type

Brushed DC permanent magnet



Nominal power rating


Motor speed

0-3000 rpm optimised at 2000 rpm




0-4.5; peak 4.5 amps, average operational 3 amps

Motor resistance

Up to B907 1.8 Ohm; B907 and after 1.4 Ohm

Start up current

1.5 amps

Start up irradiance

300 w/m2

Kick starter

Maximum 20 amps for max. 50 milliseconds


24 amps

Motor protection



2 x special alloy, fail safe

Size of brushes

Length mm 15mm, width 13mm, breadth 6mm

Rate of wear of brushes

approx 2.5mm per 1000 hours

Diameter motor


Weight of motor


Dry running

Yes (air-cooled)

Water temperature

4 degrees C - 40 degrees C

Operating temperature

Ambient + 50 degrees C

Feed pipe


High density polyethylene, nominal pressure 16 bar(10 bar can be used up to 30m depth)

Internal diameter


External diameter


Resistance to suns rays

Acceptable, but imbedding recommended

Meters per roll


Weight of roll


Dimensions of roll

External diameter external 100cm

Weight per meter


Electric cable

Type, for submersion in water, subject to national norms

Indicatively 2 x 2.5mm2 up to 80m, 2 x 4mm >80m. Larger cables may

occasionally be required. Three wire cables will be required where the use of ground cable is

legally unavoidable. NEVER USE POROUS CABLE

Type, for submersion > 100 meters)

Use 2 x 6mm. Three wire cables will be required where the use of ground cable is legally



5th class CEI 20-29 in metal coated copper

Max. resistance of wires (in- and out-)

1.5 ohms

Nominal voltage


Max.rated operating temperature

+60 deg. C

Mac. rated short circuit temp.

+200 deg. C


Rubber insulation El 1 quality completely watertight for submersion in water to at least

10 bar pressure


Neoprene EM2

Metres per roll


Weight of roll

2 x 2.5 20kg each 100m

Weight of roll

3 x 2.5 22kg each 100m

Weight of roll

2 x 4 27.5kg each 100m

Weight of roll

3 x 4 33.5kg each 100m

Typical dimensions of roll

External diameter 40cm, height 15cm

Type of protection of length with pump

Submersible, resin packed, leak-proof

Cable supplied with pump

1.5m with 3 sets of internally sealed copper strands, sealed inside an outer neoprene

sheath in turn sealed at the point of entry into the pump to the motor cover.

Cable ties


Solar panels


Any combination in parallel or in series up to 400Wp, 24-80 V

Panels to pump motor

Direct D.C. or through batteries


None required

Battery storage

None required as standard

Optional use of batteries

2 x 12V or 3 x 12V (maximum 36V)


Manual on support or with sensor

Switch type

Standard hermetically sealed type

Current regulation/kick starter

Strongly recommended - see notes Sunprimer

Panel support (Recommended)


Lattice type on 50cm thick concrete slab


250cm x 80cm x 80cm


120 kg


Hot dip galvanised mild steel

Daily tracking

1) Standard no 2) Alternative 3 point manual

Height from ground

Recommended 2m-2.5m

Resistance to wind

All recorded wind speeds

Resistance to shock

Extremely resistant

Resistance to abrasion/salt corrosion


Support pole (Alternative - no guarantees implied)


Hot dip galvanised mild steel




76mm standard


1m below ground

Joints for electric cable


Ferrule joints, shrink tubes over plastic tube with epoxy filling

Type of shrink tube

Raychem or equivalent internally glued

Measurements of shrink tube

Length 35-40cm; internal diameter 20cm

Alternative splice kit: part 1

Duraseal ferrule + heat shrink joints DS 14-16 blue for wires to 2.5mm2, DS 10-12 yellow for wires 4mm2 and 6mm2

Alternative splice kit : part 2

Raychem internally glued shrink tubes WCSM 20/6 internal diameter 20mm, length 35-40cm

Alternative splice kit : part 3

2 x Raychem internally glued shrink tubes WCSM 9/3 internal diameter 9mm, length 10cm

Alternative splice kit : part 4

Raychem ES-CAP at least 5cm for sealing off earth wire

Joints for feed pipe


Double rapid couplings

Safety rope





Notes on multiple pump installations

Subject to borehole capacity, up to five Solar Spring units can be placed in 6" internal diameter boreholes. The more the pumps installed the more experienced the installer needs to be. Competence is required to install five units in one bore-hole. Feed pipes, electric cables, and safety ropes must not get tangled with those of other pumping units.

Multiple pump installations are important because they enable considerable savings to be made on drilling costs, to the point where the cost of the solar pumping systems can be lower than the amount saved on drilling costs. Solar Spring pumps are capable of pumping at great heads and of forcing water over several kilometres if necessary to dedicated water tanks near users' houses.

For a drawing of a multiple pump installation, please refer to the drawing showing multiple pump systems.

Notes on the Sunprimer MKII controllers

The Sunprimer electronics units incorporate five functions:

1) To interrupt current connection between the PV panels and the pump when irradiance or the battery charge is such that voltage is so low, about 22V, that the pump slows down to the point where it stops. This stops the motor from being put under continuous load when stopped.

2) To start your Solar Spring pump as early as possible in the morning and keep it going as long as possible into the evening (thus extending running time), provided irradiance or battery charge is sufficient to keep the pump running. If the pump cannot start, or is turning too slowly, function 1 enters into operation. If irradiance is reasonable, function 2) will make another attempt to start the pump. A secondary timer unit attempts to start the pump at intervals of approximately two-three minutes. This timer also operates on initial starting up, so that the pump will start operating APPROXIMATELY TWO-THREE MINUTES AFTER ELECTRICAL CONTACT HAS BEEN MADE.

3) To switch nominal voltage between 48V and 24V in relation to the available power from the PV panels and pump load, so as to optimise amperage absorbed by the pump motor and adjust motor speed as required to optimise pump capacity. It does this by automatically connecting all the panels in series or in two sets each of two panels in parallel, according to irradiance and the load on the pump. This enables the pump to operate better in slightly cloudy conditions and/or earlier in the morning and later in the evening. This device performs some of the functions of traditional "boosters". The controller charges the capacitor to 60V in 48V, 24V direct, and battery applications. The controller starts in 48V mode, then switches to 24V if insufficient current is available.

4) To connect the Solar Spring pump to GOOD QUALITY external float switches and/or other devices such as pre-sostates. This is the smallest cable which comes out of the Sunprimer. It has two wires which, when placed in contact with one another or in an electrical circuit, interrupt the electricity supply. When the two wires are not in contact with one another or in an electrical circuit, the controller feeds current to the pump motor and, assuming irradiance is sufficient, the pump will start again after about three minutes. External controls or switches used should be of high quality and such that on and off contacts be made cleanly, precisely and quickly. Uncertain or irregular contacts may damage the controller and may shorten the life of the motor brushes.

5) To save pump motor and system components where specifications are not complied with during installation and/or in the presence of particular extreme or unforeseen environmental events (including freezing or blocking of the feed pipe system for any other reason or excessive draw-down of water in the borehole) where a fail-safe system is needed. For instance this function intervenes to cut current where current is greater than 4.5 amps for more than half a second. Normal starting procedures will then be activated, so the pump will attempt to start again after approximately two minutes (Sunprimer Mk II). Another device will act to cut current to the controller by putting the PV panels into short circuit when for any reason the main transistor in the controller is damaged so that the controller can no longer work properly. The pump will automatically start again once the damaged transistor has been repaired.

6) The Sunprimer Mk II controller does not have a minimum current control to switch the pump off when it is running dry. The pump can run dry for days or even weeks without suffering undue harm. It has been assumed that where dry running is not immediately obvious to users, those interested will carry out periodic checks to make sure the pump is in fact pumping water.

Main menu Solar Spring pumps.

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.


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