SUNGROW PV System Preventive Maintenance Procedure (Monthly, Quarterly & Semi-Annual)

Monthly – External Inspection

• Inspect enclosures for mechanical damage, paint damage, oxidation or corrosion

• Check windows and doors open and close freely

• Verify sealing strips are intact and sealing correctly

• Inspect foundations and footings for settlement or deterioration

• Check for corrosion, particularly in areas of water pooling

• Inspect for vermin or insect build-up and rectify

• Verify access controls remain compliant with HV regulations

• Inspect bunds, bunding pipework and level gauges

• Remove accumulated liquids from bunds where required

Monthly – Internal Inspection

• Inspect internal condition for dust, dirt, foreign objects or water ingress

• Clean internal surfaces as required

• Inspect for internal vermin or insect build-up and rectify

• Verify signage is present, legible and compliant

• Check operation of door switches, internal lights and auxiliary switches

Quarterly

• Conduct detailed visual inspection of power conversion areas

• Review enclosure condition trends from monthly inspections

• Verify no progressive corrosion, seal degradation or access non-compliance

Semi-Annual

• Verify enclosure environmental integrity (seals, glands, penetrations, strain relief)

• Inspect internal enclosure body for corrosion or long-term dust accumulation

• Clean internal compartments thoroughly

• Pass
• Flag
• Fail

Temperature

• Measure room temperature using calibrated independent equipment

• Compare with installed battery room temperature sensor

• Record deviations

• Generate and review 1-month accumulated temperature trend

Humidity

• Measure room humidity using calibrated independent equipment

• Compare with installed battery room humidity sensor

• Record deviations

• Generate and review 1-month accumulated humidity trend

Monthly – Visual Inspection

• Inspect battery cabinets and racks

• Inspect data and power cabling for loose connections

• Inspect wiring for distortion or colour change

• Inspect mechanical structures for bending or corrosion

• Inspect for dust ingress and clean as required

Quarterly

• Review battery environmental trends (temperature & humidity)

• Verify no recurring environmental excursions

• Inspect battery system areas for progressive mechanical or electrical degradation

Semi-Annual

• Verify grounding connections associated with battery system

• Inspect internal cabinet condition for corrosion, contamination or moisture

• Perform deeper inspection of cable terminations and supports

• Pass
• Flag
• Fail

Monthly

• Verify inverter is running normally via HMI

• Confirm no active faults or warnings

• Review fault history records

• Check for temperature or humidity alarms

• Listen for abnormal transformer or fan noise and compare with historical operation

Quarterly

• Review inverter performance trends via SCADA

• Identify recurring alarms or derating events

• Verify inverter returns to normal operation after maintenance

Semi-Annual

• Verify operating parameters and protection functions

• Check emergency stop functionality (where permitted)

• Verify HMI/LCD time display accuracy and replace battery if required

• Pass
• Flag
• Fail

Monthly – Visual Inspection

• Inspect transformer body and cable glands

• Check for oil leaks

• Verify oil level is correct

• Inspect general condition of transformer components

• Check ambient temperature

• Check oil temperature is within normal operating range

Quarterly

• Review transformer condition trends

• Inspect surrounding area for drainage or environmental issues

Semi-Annual

• Inspect gas relays, pressure relief valves and thermometers

• Verify operation in accordance with OEM instructions

• Perform grounding resistance checks where applicable

• Pass
• Flag
• Fail

Monthly

• Inspect switchgear for physical damage

• Check for visible signs or smells of burning

• Verify correct operation of interlocks

• Check for abnormal noise or heat during operation

Quarterly

• Confirm switchgear remains in normal operating condition post-maintenance

Semi-Annual

• Inspect electrical connections and earthing points

• Pass
• Flag
• Fail

Monthly

• Inspect CBX enclosure for:

• Check enclosure door:

• Verify enclosure seals:

• Inspect mounting structure:

• Check for corrosion:

• Inspect for vermin or insect activity:

• Verify signage:

Quarterly

• Inspect DC terminals, fuse holders and busbars for: Discoloration Signs of overheating Carbon tracking Loose components

• Inspect internal wiring for: Loose conductors Insulation damage UV or thermal degradation

• Inspect fuses: Correct rating No visible damage

• Inspect earthing conductor connections: Secure and intact

SEMI-ANNUAL MAINTENANCE

• Perform thermal imaging of: DC terminations Busbars Fuse holders

• Identify hot spots or abnormal temperature rise

• Record thermal images and temperature values

• Flag any anomalies for corrective maintenance

• Torque check DC terminations Inspect mechanical fixings: Mounting bolt Rectify loose or degraded fixings

• Inspect CBX earthing conductor and bonding points Verify secure connection to site earth system Inspect for corrosion or mechanical damage

• Clean internal and external CBX surfaces Remove accumulated dust, insects or debris Apply anti-spider or pest deterrent treatment as required Ensure vents (if fitted) are clean and unobstructed

• Pass
• Flag
• Fail

Quarterly

• Review system monitoring and performance data

• Confirm alarm functionality and data logging integrity

Monthly

• Check and clean electronic sub-systems

• Verify communication hardware condition

• Confirm data availability for reporting

Semi-Annual

• Perform alarm verification testing

• Inspect communication cabinets internally for dust or contamination

• Pass
• Flag
• Fail

Monthly

• Visual inspection of weather station structure

• Check instrument alignment and mounting

• Clean all sensors (pyranometer, temperature sensor, anemometer)

Quarterly

• Verify sensor performance consistency

• Inspect pyranometer inclination and cleanliness trends

Semi-Annual

• Inspect desiccant cartridges

• Replace desiccant when colour changes from orange to clear

• Verify free movement of anemometers

• Confirm long-term mounting stability

• Pass
• Flag
• Fail

Monthly

• Inspect grass and vegetation

• Ensure vegetation does not exceed bottom of combiner boxes

• Include areas inside the fence and within the lease boundary

Quarterly

• Undertake vegetation management works (cutting, spraying)

• Inspect internal roads and access areas

Semi-Annual

• Inspect drainage points and erosion areas

• Inspect fencing, gates and access doors

• Inspect roofs and gutters for obstructions

• Pass
• Flag
• Fail

Monthly

• Visual check of safety signage and access controls

Quarterly

• Verify security systems, CCTV and lighting operation

Semi-Annual

• Inspect fire extinguishers (AS1851 / AS2444 compliance)

• Inspect first aid kits (stock & expiry)

• Verify electrical safety equipment (LOTO, signage, emergency stops)

• Pass
• Flag
• Fail

Monthly Report

• Environmental readings and trends

• Inverter and transformer status

• Weather station maintenance

• Vegetation observations

• Defects and corrective actions

Quarterly Report

• PV array and inverter condition trends

• Security, roads and vegetation outcomes

• Spare parts and system performance summary

Semi-Annual Report

• Grounding results

• Enclosure integrity findings

• Cooling and ventilation condition

• Electrical connection inspections

• Safety and compliance verification

• Pass
• Flag
• Fail

DATE:

Technician's Signature