1 Preparation before installation: Dual adaptation of environment and equipment
1. Compliance requirements for installation environment
The installation of hybrid inverters must meet the four core conditions of "ventilation, light avoidance, dryness, and safety":
• Temperature and humidity: The ambient temperature should be controlled between -30 ℃ -60 ℃, and the humidity should be maintained between 10% -90% (without condensation) to avoid component aging or short circuits caused by high temperature or humidity
• Ventilation space: At least 30cm of heat dissipation distance should be reserved around the equipment, and the top and bottom should be avoided from obstruction to ensure that the cooling fan can exhaust air normally. If installed in a closed cabinet, an additional forced ventilation system needs to be configured
• Safety distance: Keep away from open flames, heat sources (such as heating pipes), and corrosive gases. Keep a distance of no less than 1.5 meters from flammable and explosive materials, and avoid areas prone to water accumulation to prevent rainwater from soaking equipment
• Load bearing and fixing: The installation surface should be flat and meet the load bearing standards (wall mounted ≥ 50kg/㎡, floor mounted ≥ 100kg/㎡). The wall or floor should be reinforced with expansion bolts to avoid vibration and displacement during equipment operation.
2. Safety configuration of personnel and tools
• Personnel qualifications: Installation personnel need to hold an electrician certificate, be familiar with high-voltage electrical safety regulations, and have undergone specialized training on the operation of hybrid inverters to understand equipment wiring logic and protection mechanisms
• Protective equipment: Insulated gloves (withstand voltage ≥ 1000V), insulated shoes, goggles must be worn. When working at heights, safety belts must be worn to avoid direct contact with live parts
• Tool preparation: Equipped with insulation wrench, torque wrench (used for terminal fastening, torque value needs to match equipment requirements, usually 8-12N · m), multimeter (to detect voltage and current), insulation tester (to detect insulation resistance), crimping pliers, etc. Before using the tool, the insulation performance needs to be verified to ensure no damage.
3. Inspection and verification of equipment and accessories
Before installation, it is necessary to check the equipment and accessories one by one:
• Equipment appearance: Check that the inverter casing is free of deformation or cracks, the display screen and indicator lights are intact, and the wiring terminals are not oxidized or loose
• Accessory integrity: Confirm the installation bracket, fixing bolts, insulated cables (DC lines need to match photovoltaic/battery voltage, AC lines need to adapt to grid specifications), communication lines, instructions, etc. The cable cross-sectional area should meet the current requirements (such as 10kW equipment DC lines are recommended to be ≥ 6mm ², AC lines are recommended to be ≥ 10mm ²)
• Parameter matching: Check whether the rated power and input voltage range of the inverter match the parameters of the photovoltaic array and energy storage battery (such as the photovoltaic open circuit voltage needs to be within the maximum input voltage range of the inverter, and the battery voltage needs to be adapted to the energy storage interface of the inverter), to avoid equipment damage caused by parameter mismatch.
2 Standardized installation process: complete steps from wiring to debugging
1. Equipment fixation and wiring operation
Step 1: Fixed equipment
Wall mounted installation requires first fixing the bracket to the load-bearing wall, calibrating the flatness of the bracket with a level (error ≤ 2mm), and then hanging the inverter on the bracket and locking the fixing bolts; Floor standing installation requires placing the equipment on a prefabricated cement base or metal bracket, ensuring that the body is vertical, and fixing the bottom with bolts to prevent displacement.
Step 2: Wiring operation
DC side wiring: First, disconnect the main switch between the photovoltaic array and the energy storage battery. Connect the positive and negative photovoltaic wires to the "PV+" and "PV -" terminals of the inverter, respectively. Connect the positive and negative battery wires to the "BAT+" and "BAT -" terminals. When wiring, distinguish the positive and negative poles to avoid reverse connection; Terminal fastening requires torque wrenches to operate according to the specified torque to prevent overheating caused by virtual connections; After the wiring is completed, wrap the exposed part of the terminal with insulating tape and then install the protective cover.
AC side wiring: Connect the live wire (L), neutral wire (N), and ground wire (PE) of the power grid to the "AC L", "AC N", and "AC PE" terminals of the inverter, respectively. The ground wire should be connected first and have good contact to ensure that the grounding resistance is ≤ 4 Ω; If grid connection is required, additional grid contactors and metering meters need to be connected. The wiring of the meters must follow the specifications of the power grid company, distinguishing between "incoming" and "outgoing" lines.
Communication line connection: Connect the communication line (such as RS485, Ethernet) between the inverter and the monitoring platform (or APP) to the corresponding port, ensuring that the pins correspond. When the communication distance exceeds 100 meters, a signal amplifier needs to be added.
2. Insulation testing and safety verification
Insulation resistance testing: Use an insulation tester to test the insulation resistance of the DC side (photovoltaic ground, battery ground) and AC side (grid ground) separately, with a requirement of not less than 100M Ω. If the resistance value is too low, check for cable damage or moisture damage to the wiring terminals
Voltage detection: Close the photovoltaic and battery switches, use a multimeter to detect the DC input voltage of the inverter, and confirm that the voltage is within the equipment adaptation range (such as 300V-800V) to avoid overvoltage or undervoltage
Grounding detection: Use a grounding resistance tester to measure the grounding resistance of the equipment, ensuring it is ≤ 4 Ω. If the resistance exceeds the standard, it is necessary to add grounding electrodes or optimize the grounding grid.
3. System debugging and trial operation
Step 1: Parameter Setting
Connect the inverter power supply, enter the settings interface through the display screen or APP, and configure core parameters: including grid voltage/frequency (such as 220V/50Hz), charging and discharging cut-off voltage (matching battery type, such as lithium iron phosphate 3.65V/unit), grid connected mode (grid connected/off grid/hybrid), peak and valley electricity price periods, etc. Parameter settings should refer to the equipment manual and actual application scenarios.
Step 2: No load debugging
Disconnect the load and grid switch, start the inverter to enter no-load operation, observe the display screen data: whether the DC voltage, AC output voltage, frequency are normal, whether the indicator light is error free (if the fault light is not on), whether the fan automatically starts and stops according to temperature; If there is a voltage abnormality or alarm, power off to check the wiring and parameter settings.
Step 3: On load trial operation
First, connect 10% -30% of the rated load (such as connecting lighting and refrigerators in household scenarios), run for 1 hour, and monitor whether the output power and module temperature are stable; Gradually increase the load to full load and run continuously for 24 hours, recording voltage, current, and temperature data to ensure no overheating, tripping, or other issues; The grid connection scenario requires contacting the power grid company for acceptance after the trial operation is normal. Only after passing the acceptance can it be officially connected to the grid.
3 Daily operation and maintenance strategy: preventive maintenance and status monitoring
1. Periodic inspection plan
Establish a three-level inspection system of "daily inspection+weekly inspection+quarterly inspection":
Daily inspection (remote/on-site combination): Real time data including input and output power, battery SOC, device temperature, operating mode, etc. can be viewed through the monitoring APP, with a focus on whether there are alarm messages (such as overheating and overvoltage) to ensure no abnormalities
Weekly inspection (on-site inspection): Clean the dust on the surface of the equipment and the heat dissipation holes, use a soft brush or compressed air (pressure ≤ 0.3MPa) to clean the fan filter screen, and avoid dust blockage that affects heat dissipation; Check if the wiring terminals are loose and if the cables are aged or damaged. If the terminals are found to be overheating or discolored (such as copper bars turning black due to oxidation), they need to be re tightened or replaced
Quarterly inspection (professional testing): Use a multimeter to measure the voltage and current on the DC and AC sides, and confirm that the deviation from the rated value is ≤ 5%; Use an infrared thermometer to measure the temperature of the power module and terminals. During normal operation, the temperature should be ≤ 60 ℃; Check the grounding resistance and insulation resistance to ensure compliance with safety standards; Calibrate the charging and discharging parameters and adjust the SOC threshold based on battery degradation (if the battery capacity decreases by 10%, the charging cut-off voltage can be lowered by 5%).
2. Key points of operation and maintenance for special working conditions
High temperature season: Increase inspection frequency (such as twice a week), clean up debris in the cooling channel, check the operation status of the fan. If the ambient temperature exceeds 40 ℃, install sunshades or forced cooling fans around the equipment to avoid power derating caused by high temperature
Low temperature season: Before starting the equipment, it is necessary to confirm that the ambient temperature is ≥ -10 ℃. If the temperature is too low, the preheating function can be turned on first (supported by some models), and the equipment can be started after the temperature rises above 5 ℃; When charging the battery, it is necessary to control the charging current to avoid lithium dendrite precipitation caused by low-temperature and high current charging
Thunderstorm season: Check whether the lightning protection device (such as lightning arrester) is intact, check whether the equipment is damp after rain, and if condensation is found on the wiring terminals, cut off the power and dry it before operation; The grid connected system needs to pay attention to voltage fluctuations in the power grid to avoid equipment damage caused by lightning strikes.
4 Common troubleshooting: precise positioning and efficient handling
1. Diagnosis and solution of typical faults
Inverter cannot start: First, check if the DC input voltage is within the appropriate range. If the voltage is too low (such as insufficient photovoltaic irradiance), wait for the light to increase. If the voltage is too high, check if there are too many photovoltaic arrays in series; Secondly, confirm whether the power switch is fully closed, including the DC side main switch and the device's own power button; If all the above are normal, it may be that the internal fuse is blown, and the same specification fuse needs to be replaced after power outage (refer to the equipment manual to determine the fuse parameters).
Grid connection failure and reporting "power grid abnormality": first use a multimeter to detect the voltage and frequency of the power grid. If it exceeds the equipment adaptation range (such as voltage 220V ± 10%, frequency 50Hz ± 0.5Hz), contact the power grid company for handling; If the grid parameters are normal, check whether the grid connection is incorrect, with a focus on checking whether the live wire (L) and neutral wire (N) are connected in reverse, and whether the ground wire is in good contact; If the wiring is correct, it may be a false triggering of the anti islanding protection. You can try restarting the device. If the error persists, you need to contact the manufacturer to calibrate the protection parameters.
Battery cannot be charged: first check the actual voltage of the battery. If the voltage is lower than the discharge cut-off value (such as lithium iron phosphate battery below 2.5V/cell), the battery needs to be activated through an external charger first; If the battery voltage is normal, enter the device parameter interface to check the charging cut-off voltage setting and confirm that it matches the battery type (such as the charging cut-off voltage of ternary lithium batteries is usually 4.2V/cell); If the parameter settings are correct, it may be a fault in the Battery Management System (BMS). The battery needs to be disconnected and powered back on. If it still cannot be charged, the battery health should be checked and a severely attenuated battery should be replaced.
Insufficient output power: First check the photovoltaic irradiance. If the irradiance is below 200W/㎡ (cloudy or evening), it is considered a normal power decrease; If the irradiation is sufficient, check the equipment temperature. If it exceeds 60 ℃, clean the heat dissipation channel and reduce the module temperature; At the same time, check whether the load power exceeds the rated output of the inverter. If the load is overloaded, reduce the use of electrical equipment to ensure that the load power is within the rated range; If all the above are normal, it may be due to the performance degradation of the photovoltaic panel or battery. It is necessary to test the open circuit voltage and battery capacity of the photovoltaic panel and replace the components with substandard performance.
Display screen error "over temperature protection": First, check if the cooling fan is rotating normally. If the fan stops, replace the fan motor or clean any foreign objects stuck in the fan; Next, check the ambient temperature. If it exceeds 45 ℃, improve the ventilation conditions, such as installing sunshades or adding cooling fans; If both the fan and the environment are normal, it may be a power module malfunction. An infrared thermometer should be used to detect the temperature of the module. If the local temperature exceeds 80 ℃, the manufacturer should be contacted for repair or replacement of the power module.
2. Emergency response and safety precautions
Emergency shutdown: In case of equipment smoking, abnormal noise or pungent odor, immediately press the emergency power-off button, disconnect the DC and AC switches, stay away from the equipment and call the manufacturer's after-sales phone number. It is forbidden to disassemble it by oneself
Fault record: When a fault occurs, the fault code, fault time, and current operating conditions (such as load power and ambient temperature) should be recorded to facilitate the manufacturer to quickly locate the problem
After sales linkage: If the fault cannot be resolved by itself (such as internal component damage), qualified after-sales personnel should be contacted for repair. Non professionals are prohibited from disassembling high-voltage components to avoid electric shock or secondary damage to the equipment.