Workplace Safety: Regulations and Risk Prevention

Riesgos

• For operators, businessmen, and technicians it is important to know:
• Safety Regulations
• Appropriate means and tools
• Personal and collective safety equipment

Generalities

• Work involves different guilds
• Poor management in one area affects others
• Management of Occupational Risk Prevention is based on standard UNE 81900
• All companies and their staff are expected to use safe working methods

5 Golden Rules

• Always comply with the five golden rules to work without tension
• Disconnect
• Prevent any possible feedback
• Verify the absence of voltage
• Ground and short circuit
• Protect against live elements and signal the area

Protection Against Storms

• Protection levels are divided into external and internal.
• External
• Objective: Prevent direct impact and channel current to ground safely
• Internal
• Objective: Eliminate or reduce damage that can cause overvoltages

Classification of Safety Signs

• Warning signs alert to a hazard
• Prohibition signs prohibit behaviors that could cause danger
• Mandatory signs enforce certain behaviors
• Information signs provide information on how to proceed or act

Response to an Accident

• In the event of an accident, apply PAS rules:
• Protect
• Alert
• Help
• Recognize the victim's vital signs:
• Consciousness
• Breathing
• Pulse

Strategic Planning

• Have all the necessary resources available when needed, including equipment, lifting devices, handling devices, and transportation
• Materials and supplies should be on site when needed for assembly.
• Meet the objectives specified according to established planning
• Control materials, ensuring they are properly marked and tracked at all times.
• Ensure the right human resources are assigned to each assembly phase.

Assembly Planning

• General information
• Characteristics
• Type
• Necessary materials
• Tools
• Machinery
• Human resources
• Timing and duration of use
• Delivery Schedule Details
• When it is made
• Delivery times
• Reception schedule
• Relations with the order schedule
• Time the delivery should arrive at the installation
• Planning
• Tasks in a coherent and orderly manner
• Gantt or PERT charts that show when each task should be started and completed
• Control indicators for assessment of progress and completion
• Contingency Plans
• Actions for unexpected situations, such as changing suppliers or altering the order of execution

Reorganization

• Phases
• Collect and verify information
• Verify placement coordination
• Replan in place
• create updated documentation

Climactic Conditions

• Roof Assembly
• Group and block ballasts to prevent movement along the slope due to thermal expansion
• Add a flexible layer between the roof and the support structure and ballasts

Component Labeling

• Includes warnings of the risk of electric shock

Tight Cases

• The IP level should be respected based on the surroundings and installation
• Doors and lid should be secure and easy to open

Quality of Connections

• Properly corrugated and tightened connectors to avoid overheating.
• Poor electrical contact due to loose connections can internally cause electric arcing, resulting in losses and the risk of fire.

Temperature Control

• Refrigerate them when they have electronic components

Connectors

• Use same model and manufacturer connectors

What is Maintenance Management?

• Coordinated activities to maintain and restore equipment and ensure the installation's performance and reliability.
• Extend service life
• Reduce downtime
• Effectively manage maintenance costs

Issues

• Lack of defined maintenance business process
• Inadequate support systems for management
• Preventative maintenance plans that are not optimized
• Low level of development and predictive maintenance
• Limited use of available information
• Warranty claims management:

Additional issues

• Stock management, ensuring optimal stock to meet the business objectives
• Rapid technological obsolescence, which accelerates equipment replacement

Types of Maintenance

• Preventative Maintenance
• Predictive Maintenance
• Corrective Maintenance

Preventative Maintenance

• Aims to prevent or reduce the consequences of equipment failures
• The objective of this type of maintenance is to prevent failure from happening
• Tests are scheduled for a specific period or amount of equipment usage
• It relies on the estimation of an element’s probability of failure
• Tasks include:
• Cleaning modules
• Reviewing connections
• Testing protections
• Cleaning ventilation filters

Predictive Maintenance

• Using real-time information to predict a possible failure before it happens
• Actions are planned based on the information for the particular situation
• Based on monitoring physical parameters (power, temperature, humidity, lubrication)
• When parameters reach a level of deterioration, procedures are followed
• This approach is similar to preventative maintenance except that the actions are performed when necessary
• Use monitoring data to determine critical deterioration levels
• This type of maintenance can also include:
• Control of the inverters
• Control of production of the modules
• Control of the temperature of the modules
• Least common in photovoltaic plants

Corrective Maintenance

• This maintenance is performed after a failure occurs, with the intention of returning the device to its original state
• The inconveniences are:
• Unscheduled downtime
• Excessive cost and maintenance time
• Severe damage
• This was the only maintenance strategy before the 1950s
• Activities are:
• Replacement of modules, inverters, transformers, cable, and protection

Risks of Performance Loss

• Challenges in the design, operation, and maintenance of large photovoltaic energy systems due to the uncertainty and variability of environmental factors.
• Components with different degrees of vulnerability
• The reliability is related to the temperature, power losses
• Increased stress on the operating system may shorten operational cycles due to sudden changes in environmental conditions, such as temperature and atmospheric agents
• The generation of photovoltaic within the power distribution grid can cause a reverse power flow that affects the installation, also causing disconnection and stoppage of the park with abrupt fluctuations in red voltage

Failure Characterization: PV Modules

• Stationary elements with a low probability of failure
• Failures of external origin: fragility requires transportation, handling and assembly care
• Vibrations or blows, faulty connections, rays or sabotage
• Failures Origin
• Power loss
• High repair costs

Failure Characterization: Inverters

• A critical element, high cost of repair and / or replacement can occur
• They incorporate sensors and measuring devices that monitor its operation, if there is an abnormal procedure the alarm is registered
• By analyzing the registered data it is possible to locate the source module, the motor or the network
• External Origin Failures:
• Poor installation, incorrect strings
• Grid failures
• Failures of Origin
• Failures in operation: insulation, grounding, transformer
• Failures in starting and stopping relays commutation
• Communication failures: since no production loss is recorded.

Failure Characterization: Others

• Problems in transformers or red falls
• Prolonged partial shades
• Incorrect positioning of followers

Thermography

• A safe method for detecting failure.
• Using a thermal imaging camera, quickly identify problems in photovoltaic systems with approximately 600 W/m² of solar radiation
• Diodes of defective bypasses
• Faulty contacts and short circuits in solar cells
• Humidity and dirt ingress
• Cracks in cells or module crystals
• Open circuit and disconnected modules
• Poor connections i.e. power losses caused by connecting photovoltaic modules with different potency
• Wiring errors and cold joints
• Symptoms of aging and stress