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LEARNING GOALSDescribe the steps involved with commissioning a new PV system. Identify the maintenance tasks involved with maximizing array output, battery health, and other equipment operation. Develop a maintenance plan based on system configuration, installation, and location. Compare the various methods of monitoring system parameters for performance verification and troubleshooting. Troubleshoot PV systems based on a logical and efficient process. COMMISSIONINGOnce a PV system has been installed, inspected, and approved, it can then be commissioned. Commissioning is the starting and operation of a PV system for the first time. Commissioning is also the time when the installer formally transfers responsibility for the system to the owner or operator, and marks the completion of the installation contract. Any warranties or service agreements should be finalized at commissioning. The requirements for commissioning vary depending on the complexity of the system, though some general guidelines apply to most situations. Final Checkout: Before any PV system is fully operated for the first time, the system should be checked thoroughly to ensure that the installation is complete and that the system is safe and ready for operation. A final checklist includes many of the same items as on maintenance, testing, and inspection checklists. All disconnects should be in the open (OFF) position during the final checkout. Final checkout should include attention to details associated with a neat and professional installation. All tools and debris should be removed from the site and the area cleaned. The customer's property should be restored to its original condition or better. Any property belonging to the customer that is damaged during the installation must be repaired or replaced at the installer's expense. General Start-Up Procedure: A general start-up procedure begins at the array and ends at the loads, though exact procedures may differ. Initial Startup: The initial startup is the first time that all the system components are energized. A general start-up procedure begins at the array and ends at the loads. If there are any installation problems, this reduces the chances of causing safety hazards and damaging equipment. One at a time, each disconnect is closed and each component is switched ON, and voltage and current are compared with expected values. (Array and battery bank voltages should be confirmed before closing their disconnects.) Meters, indicators, and displays on charge controllers and inverters are used for measuring and verifying system parameters. If at any step the system parameters are outside of the acceptable range, the startup should be aborted and troubleshooting procedures should be used to find the cause of the problem. It’s critically important to review all equipment documentation for any special start-up procedures. Improper startup may cause safety hazards, component damage, or impaired performance. Some component manufacturers specify variations on the general start-up procedure, which should always be followed. For example, some interactive inverters require that connections be made in a certain sequence to properly synchronize with utility-supplied power. The manual details each step and typically includes troubleshooting procedures for out-of-range results. The voltage and current measurements take enduring the initial startup should be recorded and kept with the other system documentation. These measurements serve as a baseline that will be helpful for subsequent maintenance and troubleshooting tasks. System Documentation: A complete documentation package should be assembled and given to the customer at the time of commissioning. The package should include system and equipment manuals, permitting documents, and any warranty or service information. Comprehensive manuals for package systems, such as those pre-engineered by an integrator, may be available. System manuals generally include safety requirements, electrical and mechanical drawings, parts lists with sources, system warranty information, and procedures for operation, maintenance, and troubleshooting. A documentation package should include the manuals for all major components, including PV modules, inverters, and charge controllers. Copies of permits, certificates of inspection, and utility interconnection agreements should also be included. These documents, in addition to installation contracts, may be required for insurance or financing purposes. Original documentation should be kept in a safe place where it won’t be easily damaged, but will always be available, If it’s desired that operating or servicing instructions be posted, copies rather than original documents should be used in order to avoid loss or damage of the original documents. The installer should also retain copies of all documentation provided to the owner to aid with any warranty claims or follow-up service. --- Maintenance Safety--Proper safety precautions must be taken during all aspects of PV-system installation, operation, maintenance, and troubleshooting. These tasks can expose personnel to electrical, chemical, explosion, fire, exposure, and ergonomic hazards. Qualified persons have a thorough understanding of the equipment and procedures involved, and the skills and knowledge to recognize and mitigate the associated safety hazards. Specific safety regulations and standards required for construction and maintenance activities are covered in OSHA regulations 1926 and 1934 and NFPA 70E, Standard for Electrical Safety in the Workplace. Depending on the system and the task, special tools and equipment, fall protection, and personal protective equipment (PPE) may be required. PPE includes face shields, safety glasses, hoods, helmets, harnesses, footwear, and clothing appropriate for the tasks to be conducted. Additional safety equipment may be permanently installed with the PV system, such as fire extinguishers and smoke detectors. All sources of power should be disconnected, de-energized, or disabled before con ducting any maintenance on electrical equipment. If tasks require working on energized equipment, special PPE must be used. It’s highly recommended to work with a partner, especially around hazards. --- Commissioning Checklist: -- Installation conforms to system design documents -- Conductors are of appropriate types and sizes -- Wiring is correct, protected, and secure -- Terminal connections are tight and properly identified -- Equipment is securely mounted -- Array mounting system is secure -- Roof penetrations are properly weather sealed -- Safety features are installed and operational -- Applicable warning and operational labels are posted -- Job site is clean, neat, and orderly -- Documentation package is complete --1. A commissioning checklist should be reviewed before the initial startup of any PV system. Commissioning, maintenance, and troubleshooting tasks include setting and adjusting parameters on inverters or charge controllers. User training: Installers should provide operation and some maintenance training to the PV-system owner. The appropriate level and amount of training will vary depending on the type of system, the capabilities of the owner/operator, and the owner's! operator's expected involvement with the system. At a minimum, the owner should understand the overall functions of system components, principles of operation and safety, and maintenance requirements. Means of disconnecting the system should be demonstrated, and the owner should be given clear instructions about what to do or who to contact if service is required. For relatively simple residential interactive systems, user training may require only a short walkthrough. If the customer observes much of the installation and commissioning processes, additional training time may not be required. For stand-alone and hybrid systems, additional training on safety and maintenance requirements is recommended, particularly regarding batteries, charge controllers, engine generators, dedicated electrical loads, and other equipment as applicable. Energy-management training is especially important for stand-alone systems. The customer must be aware that excessive load usage may result in over-discharged batteries and failure to meet system load requirements. In addition to required system labeling, posting line diagrams, operating procedures, and programming instructions near key components can be very helpful when explaining system operation during user training, and for maintenance and troubleshooting tasks after ward. The installer should also review the con tents and key sections of system documentation with the customer. Quality documentation greatly facilitates user training and allows the owner to continue learning about the system after the commissioning. --3. Customer Walkthrough: A detailed walkthrough allows the installer to explain the basic operation of the PV system and the maintenance requirements to the owner. System Warranties: Major components such as PV modules, inverters, charge controllers, and batteries typically include warranties from the manufacturer. Some integrators and installers offer additional warranties on selected subsystems or the entire system. Terms vary widely regarding what is covered by a warranty and the length of time a system or component is covered. Installers may also extend warranties by offering a service contract. Local contractors may work under an agreement with a large national integrator that backs warranty claims for systems and major components installed by its recognized installers. The installer should discuss and clarify all warranties with the system owner at the time of commissioning. This includes the method and manner in which the warranties are exercised, such as through the installer or dealer or directly with the product manufacturer. Next: PV Systems--Maintenance |