T.E.(Terry) Manning
Schoener 50
1771 ED Wieringerwerf
The Netherlands
Tel/fax 0031-227-604128
Homepage: http://www.flowman.nl
E-mail:pumps@flowman.nl
FLOWMAN
ADVANCED PUMP TECHNOLOGIES
Edition 06: 22 December,2002
SOLAR SPRING SOLAR PUMPS
INSTALLATION
The following pages are about sealing the well, lightning and freeze protection and the use of accessories. If you are more interested in other aspects concerning installation, please return to
INSTALLATION INDEX
SEALING THE SYSTEM
It is most important your bore-hole be completely sealed off once your Solar Spring pump has been installed. This is to stop pollution of the water in the bore-hole through events such as animals and insects falling down; soil, sand, dirt or animal dung entering the water and/or the bore-hole, and, finally, to stop the water pumped from going back down the bore-hole.
We recommend that the bore-hole lining pipe be allowed to protrude several centimetres above ground level; that concrete borehole exit support be made sloping from the borehole outwards, so as to ensure drain off water from around the bore-hole.
In particular, it is necessary to seal off, as carefully as possible, the centre hole where the feed pipe, electric cable, safety rope, and, where used, sensor cables, pass, or use a pitless adapter.
LIGHTNING PROTECTION
At sites considered highly exposed to lightning which can damage PV panel by-pass diodes and internal components of Sunprimer electronic controllers, a lightning conductor made from a large horizontal conductor placed at a reasonable height above the panels and connected at each end through two good conductors to two good earth contacts placed a reasonable distance away from the equipment, may be used. Such lightning protection should only be installed by expert electricians, scrupulously respecting applicable safety regulations. The basic protection so obtained can be further improved by protecting all the electrical wires from the panels to the controller and from the controller to the pump, by housing them in strong metal pipes similar to those used by plumbers, and connecting the metal pipes and the metal box of the controller to earth contacts placed a long way away from those of the lightning conductor. It is not however considered possible to eliminate all risk of lightning damage. Insurance coverage for damage by lightning is usually avialable.
STRUCTURAL GROUNDING
Ground the metallic structure of your solar array. Use a minimum of one 3m (8 foot) copper plated ground rod, or equivalent, preferably in moist earth. In an area of high lightning exposure, where the earth may be very dry (non-conductive) we recommend running a length of BARE copper ground wire in your pipe trench, perhaps 30m (100 feet) beyond the ground rod. This will help discharge static charges into dry earth. If you have a steel well casing, you may use it as your ground rod. Drill and tap a hole to make a strong, bolted connection to the casing.
ELECTRICAL GROUNDING
DO NOT GROUND either the positive or the negative electrical wires. We have found the best lightning protection results from grounding the metallic structure only and NOT grounding the power wiring. Exception : You may connect the pump to a battery based home power system with a negative ground. If the wiring distance to the pump exceeds 50 feet (17m) - particularly in a high lightning area - the use of DC rated surge protection devices is recommended.
EXCEPTION. Where system grounding is unconditionally required by electrical authorities, ground the yellow/green PV array negative lead on the controller. Do NOT break its continuity in your array disconnect switch. Where your system is so grounded, a DC rated surge protection device MUST be fitted. We believe electrical grounding INCREASES the risk of lightning damage and should be avoided wherever legally possible.
ADDITIONAL LIGHTNING PROTECTION may be advisable in case of:
a)Isolated locations on high ground in severe lightning areas
b)Poor grounding potential because of dry, rocky, or poorly conductive soil
c)Wire runs between arrays and well-heads or between controllers and remote float switches exceed 30m (100ft).Fit an appropriate surge protection device. In case of poor grounding potential, bury gauge 6 (or double gauge 8) BARE copper grlounding wire in a trench at least 30m (100ft) long, with one end connected to the array structure.
FREEZE PROTECTION
Sunprimer Mk I/d and Mk I/e controllers will automatically switch your pump off where the feed pipe system is blocked because of freezing or for any other reason. However, since the pump will then not pump any water, steps should be taken to try to avoid the freezing of the water in your system.
One method is to bury all piping below the frost line (refer to the use of pitless adapters in the preceding pages). Another method is to drill a tiny "weep hole" in the drop pipe below frost line. This will cause a constant, but small, leakge, causing the pipe to drain slowly after the pump stops. This works well if the distance from the well to the tank is short, and the pipe spills into the top of the tanks.
WARNING !! USE OF HIGH VOLTAGE PANELS IN VERY COLD AREAS.
The voltage of PV Panels increases as temperature decreases. The transistors used in the Sunprimer Mk I unit are suitable for voltages up to 100V, which allows, in the case of use of 4 conventional PV panels each with a nominal voltage of 12V, protection to -20 degrees centigrade. As panels warm up when exposed to the sun, -20 degrees C. is considered safe for utilisation in any part of the world. Some new panels currently (November 1996) appearing on the market, such as the BP 590 modules, have a nominal voltage which is higher than 12V. This may mean that the voltage limits of the Sunprimer transistors reach their maximum at -5 degrees C. In very cold areas, it may in such cases be advisable to place a voltage limiter between the panels and the Sunprimer unit, and/or to consult your supplier.
OPTIONALS FOR PRESSURE GROUPS
Sets of pressure presostate groups may be connected to the pump for automatic household water supply, both where the Solar Spring is used directly connected to PV panels or where it is used (with Mk I/e controllers) together with battery sets. This 0equipment MUST operate on the two wires of the smallest cable coming out of the Sunprimer controller. When the two wires are in contact with one another or in an electrical circuit, the Sunprimer controller cuts current flow to the pump. When the two wires are not in contact with one another, or not in circuit, the Sunprimer controller supplies current to the motor.
TYPE OF SWITCH REQUIRED
While most float-switch units cut current on contact and incorporate good quality switches, only a few pre-sostate groups currently in commerce offer the possibility of switching the pump off when contact is made as is required by the Mk I/d controller. Further many presostates in commerce seem to incorporate extremely poor quality switches. Fortunately, good quality presostates with the required connections are available in equipment designed for use with compressed air. Pre-sostates used for compressed air, fitted where required with an appropriate water filter, are therefore warmly recommended. They must be connected to the dedicated wires of the controller and NOT to the panel/controller cable.
WARNING!
It is prohibited to make a float switch or pre-sostate connection by intervening on the electric cable joining the PV panels with the controller unit. The small cables from the controller have been expressly dedicated for this purpose. If either the pre-sostate used is of bad quality and/or the switch incorporated in it is a bad quality one, then the emergency circuit of the controller will act to cut all operations and protect the pump motor while the main transistor of the controller itself may in some cases burn out. On- and off-switching must be done using high quality switches with a rapid and precise opening and closing. Switches which are slow and hesitant have a very high probability of burning out the controller. This is true not only where the switch were to be placed on the panel-controller cable but also, at least in some cases, where it is used with the small controller wires. The difference in the probability of damage to the controller itself is that while the panel cable is crossed by many amps, the small dedicated controller cable is crossed by just a few milliamps and external switches should therefore always be connected to the dedicated controller cable and not to the main panel-controller cable.
Water flow must in NO CIRCUMSTANCES be blocked by taps, valves or similar, as these could cause a dangerous build-up of pressure within the pumping system.
MANUAL SWITCHES
An AC waterproof 30 amps single phase (two pole) on/off swtich may be placed BETWEEN THE PV ARRAY AND THE Sunprimer controller. The switch should be wired to disconnect the positive from each half of the solar array.
WARNING !!
NEVER place a switch between the Sunprimer controller and the pump.
BATTERY CONNECTIONS
GENERAL COMMENTS
Use the Mk I/e controller with battery installations, NEVER the Mk I/d unit. The Mk I/e controller has both overcharge control and low voltage disconnect incorporated to protect the pump motor.
Use 24V-36V battery systems. NEVER use 48V battery systems!
Use ONLY deep-cycle batteries.
If the pump starts comfortably after connection with the battery system, the battery installation is in order. If the pump does not start, then increase cable size and eventually use a smaller cam.
BATTERY WIRING FOR 24V SYSTEMS USING MK I/E CONTROLLER
Switches inside the Mk I/e controller have already been put correctly in position, with the black panel mode switch situated under the supplementary circuit in "Four panels" mode, and the switch on the supplementary circuit near the float switch wire already in "ON" position.
Wire as for the Mk I/d unit (refer to
Connection Sunprimer to Panels, but INSERT A 3 AMP FUSE on the positive (brown) wire between the battery set and the controller.
If the controller is not new, check switch positions before proceeding.
PROTECTION OF BATTERY GROUPS
The Mk I/e controller incorporates a battery protection function. 24V battery systems are irreperably damaged if their voltage goes down to about 21.6V. The Mk I/e unit therefore cuts current to the pump motor when battery voltage (for a 24V sent) reaches about 22.4V, which indicates that the batteries have lost 90-95% of their full charge.
If a voltmeter is placed in the circuit between the batteries and the Mk I/e controller, the voltage shown with the pumped stopped will always be about 24V, whether the batteries are flat or fully charged. To find out whether the batteries are flat and how flat they are, the voltmeter must be watched the moment the pump is switched on. If the voltage is slightly more than 22.4V, the pump will start. The moment the voltage goes below about 22.4V the controller will switch the pump off and try to start the pump again once every three minutes.
Before checking battery voltage on pump start-up, amke sure there are no other resistances in the circuit between the batteries and the controller,as these could falsify the result.
CHECKING BATTERY INSTALLATIONS
To carry out a check on the operation of the pump using batteries, it is usually enough to use a commercially available tester (ampmeter) in the pump circuit.
If the newly installed pump does not produce water but absorbs the current shown in the performance tables then either the pump is not submerged or it cannot self-prime, in which case please refer to the section on testing after installation.
If the newly installed pump starts but absorbs a current which is higher than that shown in the capacity tables, or where a safety switch or fuse jumps, AND the pump does not produce any water, then either the feed pipe is blocked or the pump cannot start because the load is greater than what the pump can handle. If the feed pipe is not blocked, then the load on the pump must be reduced by doing the following IN THIS ORDER:
Reduce submergence
Reduce cable length
Increase cable size
Use a smaller cam size.
If the pump suddenly stops working after several years' service and is not absorbing any current even though the rest of the system is in order, then either the cable is broken or the motor brushes need replacing. To carry out a check in such situation, a 10000 Ohm resistor has been placed inside the motor in parallel with the brushes. If the overall electrical resistance of the circuit is measured with a tester at the two external ends of the motor cable BEFORE lifting the pump and the resistance is found to be about 10000 Ohm, then we know the brushes need replacing. If, instead, we find a resistance which is practically infinite, then we know the cable is broken.
If the pump after a period of normal operation, absorbs the current foreseen in the performance tables or a current which is slightly lower than that, but fails to produce any water, then the water level in the borehole has gone down and the pump is running dry. This will not harm the motor but will defeat the reason for having made the installation in the first place.
If the pump after a period of normal operation, absorbs a current which is higher than that foreseen in the tables but produces no water, then the feed pipe is blocked. The Mk I/e controller will act and automatically switch the pump off.
Optionals : sensors
Where, as is usual, the Solar Spring is installed with a Sunprimer controller, switches or similar connected with optional equipment such as level sensors should be connected to the two wires of the smallest cable coming out of the Sunprimer controller unit. A number of electronic sensors can be used to help make your Solar Spring system more practical to use. Others may help you conserve your Solar Spring system.
The Sunprimer controller has been expressly fitted with wires for sensors, amongst which :
1) Float switches, which are used to switch off the pump (and therefore further delivery of water) where the water tank, or other recipient or system into which the water is fed, is full. The sensor switches the pump motor on automatically when the water level drops. The float switch must make contact on rise, to turn the pump off. If there is no contact, the pump is in ON mode. This has been done in order to ensure that in case the float switch wires or the float switch itself are damaged, the pump will continue working.
2) During interruptions of pumping operation, available power from the PV panels is not being utilised. A device can, in such circumstances, be placed between controller and panels to switch automatically over to the charging of batteries for use with other equipment and/or for subsequent use with your Solar Spring pumping system itself. Where batteries are coupled to the Solar Spring pump, the pump can also be used at night or when irradiance is too low to drive the pump directly. Storage of energy in the form of water is however usually considered more efficient than battery storage.
3) Dry running. Your Solar Spring pumping system is unique in that it can run dry, and water level sensors in the borehole are not necessary. However, running dry would be a waste of energy, cause unnecessary aggravation of wear and tear on the pump, and defeat the purpose of the installation. THE PUMP SHOULD ALWAYS BE INSTALLED BELOW THE LOWEST SEASONAL LEVEL OF WATER IN THE BORE-HOLE. This is always possible with Solar Spring pumps because they can support very deep submergence.
When the two wires of the smallest Sunprimer controller cable are connected with one or more external devices such as switches, float switches, pre-sostates, they enable pump operation to be controlled at a distance. The colours and the polarities of the wires are unimportant, and the electrical currents involved are just a few milliamperes. If the two wires are not used, they should each be separately well insulated.
Optionals : meters
As a user of a Solar Spring pumping system, you may wish to carry out cost and benefit analyses in relation to the running of the Solar Spring system. We are eager to cooperate with you in every way to help you build up and elaborate your statistics. We always seek your authorisation to use your data for general statistical purposes of interest to the general public. In order to carry out such analyses, a minimum instrumentation is needed:
This is :
1) A water meter, to measure the water pumped by your Solar Spring system, measured in cubic metres. Accuracy of the data, on a daily, monthly or seasonal basis, will depend on the number of readings taken. More refined automatic data logging equipment with accurate timing falls within the field of scientific research, and is therefore outside the scope of the optionals foreseen in this manual. We assure our strong support to Universities, testing organisations and interested parties who wish to carry out detailed data logging programmes directly connected with the use of the Solar Spring pumping system.
2) A simple electronic meter at controller and/or at motor point to measure power input into the motor. Comments under 1) above apply to this meter too.
THE TWO METERS LISTED ABOVE, WHEN USED TOGETHER OVER THE SAME TIME SPAN, WILL SUPPLY INCONTROVERTIBLE EVIDENCE OF THE GLOBAL SUB-SYSTEM EFFICIENCY OF YOUR SOLAR SPRING HORIZONTAL AXIS SUBMERSIBLE PISTON PUMP GROUP.
The use of taps, valves and the like may have unforeseeable consequences and is SEVERELY PROHIBITED. Water flow must be controlled by cutting the supply of current to the pump motor.
Go to: INSTALLATION INDEX
FOR MORE INFORMATION ON THE SOLAR SPRING PUMP PLEASE GO TO:
SOLAR SPRING COVER PAGE
RETURN TO:PRODUCTS OFFERED
If you cannot find the information you require on these pages, please contact Terry Manning
by e-mail on : pumps@flowman.nl or
telephone or fax him at 0031-227-604128.
E-mail Terry Manning