Solar PV systems must be installed safely by a licensed electrician in accordance with the manufacturer’s instructions. We recommend using an accredited solar installer with an established track record and good after sales service. We also suggest involving your regular electricity service provider in the process, and if the system is for irrigation, your regular irrigation engineer.
The key to site safety is knowing the potential hazards of your site and managing these effectively. Hazards typically associated with solar PV-powered water pumping systems can be divided into two categories: electrical and non-electrical hazards.
Working with electricity is hazardous. Working with electricity and water in the same system requires increased care during and after installation. Below are some key guidelines for working with solar electricity in Australia.
- According to Australian Standard S3000, electrical work on any sections of a solar PV system that have voltages greater than 120V DC or 50Vrms AC must be performed by a licensed electrician.
- Solar modules will produce electricity whenever sunlight hits them, and attempting to cover them (eg. with blankets) to stop them generating is not a safe practice.
- Solar PV module connectors should be the same make and model as each other; using imitation or ‘compatible’ connectors is against Australia standards (AS5033) and can be dangerous.
- All wiring should be considered live and treated as live. The voltage and current values of each wire should be measured, and exposed wire ends should be terminated appropriately to prevent anyone from coming into contact with them.
There are several non-electrical hazards to keep in mind when installing a solar PV pumping system. Solar pumps are often installed in exposed, remote areas, so it is especially important to avoid injuries. Never work on a solar pumping system alone. Some common non-electrical hazards include:
- Sun exposure: Solar systems are installed in exposed locations with limited shading so anyone installing such a system is at risk of exposure to sunburn and potentially, heat stroke. The risk of heat stroke can be reduced by wearing a hat, cool clothing and high-SPF sunscreen, taking regular breaks and drinking plenty of water;
- Slips and trips: Worksites with rough or slippery terrain can increase the risk of slips and trips for people carrying equipment;
- Strains: Solar pumping systems include components that are bulky and heavy, so it is important that anyone involved uses appropriate lifting methods. In some cases, lifting aids may be required to assist with moving heavy equipment;
- Cuts and burns: Components of a solar pumping system (module frames, bolts, nuts, etc.) can have sharp edges and may get very hot on sunny days. Gloves should be worn when handling this equipment to prevent cuts and burns; and
- Animals: Often solar pumps are installed in rural areas frequented by snakes, spiders and other insects. Care should be taken when opening equipment. System installers should have ready access to first aid, including treatment for bites from venomous and toxic species common to the area.
Installing the array and electrical wiring
The electrical components of a solar pumping system should be installed according to Australian standards and the manufacturer’s instructions.
Many solar pumping system packages include solar modules with interconnecting cables/connectors set up for ‘plug and play’. These modules should be installed and connected according to the manufacturer’s instructions. If system components – say, pumping equipment and solar modules – are to be provided by different suppliers, suitable advice should be sought from the solar pump manufacturer, or from a qualified solar installer regarding the installation and electrical connection of the new solar PV system to DC pumping equipment.
The solar array and the mounting system should be installed according to the manufacturer’s instructions. Correctly fixing the solar modules to the mounting frame is particularly important. The manufacturer’s instructions will dictate the allowable clamping points to the solar modules and the recommended installation methods. Unless the solar array and framing are installed according to the manufacturer’s instructions, and to suit the prevailing conditions, the structural loadings of the equipment will be compromised.
The wiring between the array, system controller and electric motor should be installed according to Australian standards and the manufacturer’s instructions. This includes selecting the correct wire sizing and protection devices: using undersized cable, for instance, would result in higher electrical losses. The electrical schematics of a DC-configured and an AC-configured solar pumping system are shown in Fig. 64 and Fig. 65, respectively.
Note: Some of the components specified in the electrical schematics may be combined into one device. It is important to check that all components are contained in the system – or, if not, that suitable reasons for this are given by the supplier prior to installation.
Australian standards covering the installation of and safety requirements for solar PV arrays
Both DC and AC systems
- ‘Earthing PV Array’: Clause 22.214.171.124 and Appendix B2 AS/NZS5033:2012 and Section 4 AS/NZS 4509.1
- ‘PV Array Frame Installation: AS/NZS1170’, install to manufacturers specifications and Section: 2.2 AS/NZS5033:2012
- ‘Electrical Equipment – Sizing and Selection’: Section 4 AS/NZS5033:2012 and Section 3 AS/NZS4509.1
- ‘DC Cable Sizing’: Section 3 AS/NZS4509.1, Section 3 AS/NZS5033:2012, AS/NZS3000 and AS/NZS3008
- ‘Battery Current Protection’: Section 3 AS/NZS4509.1 and Clause 3.3.3 AS/NZS5033:2012
- ‘Optional Battery Storage’: Section 7 AS/NZS4509.1
- ‘Sizing of Protection Devices’: Section 3 AS/NZS5033:2012 and AS/NZS4509.1
- ‘System Commissioning': Section 10 AS/NZS4509.1
Only DC systems
- ‘DC Cable Sizing and Connection to Loads’: Section 4 AS/NZS 4509.1, Section 3 AS/NZS5033:2012, AS/NZS3008 AS/NZS3000
Only AC systems
- ‘Multi-mode Inverter Compliance’: Clause 2.1 and Section 4 AS/NZ4509.1
- ‘Optional Generator’: Section 6 AS/NZS4509.1
- ‘AC Electrical Cable’: Section 3 and 4 AS/NZS4509.1, AS/NZS3008 and AS/NZS3000
Installing pumps and piping
Typically, a solar pumping system requires installation of electrical, mechanical and structural equipment. Contracting an experienced company, or its personnel, is generally the best way to ensure the successful installation and long-term operation of the system.
If you opt to install pumping system components independently, it is important that you, or whoever you contract, follow the manufacturer’s instructions in full. It is advisable that before you begin the installation, you set out the relevant guides and equipment in the correct chronology, as detailed by the pump manufacturer’s installation instructions.
The pump and motor should be mounted firmly on a suitable base, with attention given to alignment of the pump and motor on this foundation, and to the alignment of the pump and the motor (if these are not already aligned).
Piping should be installed so that it is supported and anchored independently. The piping should not put any weight on the pump attachment.
System commissioning occurs once the system’s components have been installed. A general guide to system commissioning is as follows.
- Check electrical connections: Check that the physical cabling is securely fastened and then check the electrical system for continuity.
- Check water connections: Examine the pipes and the connections between these pipes and the pump, to ensure that they are secure and supported.
- Check pump: Check that the pump and motor alignment are correct; check the pump lubricants; and inspect any seals.
- Prime pump (if required): Some pumps will need to be primed initially; this usually involves filling the casing with water.
- Turn on array: Check the output voltage and current of the array.
- Turn on the control systems: Check the system readings against the manufacturer’s specifications.
- Turn on the pump: Following the manufacturer’s instructions, start the pump. Monitor its pressure and water flow to confirm that the system is operating correctly.
- Observe pump operation: Check for leaks and monitor system readings while the pump is in operation.