Solar Maintenance Guide

Cleaning: how often and how

In most of Gujarat, clean panels every 15 to 20 days during the dry and dusty months, and monthly during the monsoon when rain does part of the job. Sites near highways, construction, cement plants or industrial estates need more frequent cleaning. Use plain water with a soft brush or microfibre mop, early morning or late evening when the glass is cool. Never clean hot panels with cold water, never use detergents, abrasives, or a high-pressure jet, and never walk on the modules.

• Best time: before 9 am or after 6 pm
• Water only; soft brush or microfibre mop
• Never step on panels or lean on the frames
• Check for bird droppings and leaf litter between rows

What dust actually costs you

A moderately dusty array loses roughly 5–8% of its output, and a badly soiled one can lose 15–25%. Because the loss builds gradually, it rarely feels like a fault — it just shows up as a slowly rising electricity bill. Comparing generation before and after a cleaning cycle on your monitoring app is the fastest way to see whether your cleaning interval is right for your site.

Monitoring habits

Check your monitoring app weekly rather than daily. Compare this week against the same week last month and against a neighbouring system if you have that reference. A healthy system in Gujarat averages around 4 units per kW per day over the year. A single dull day means nothing; a sustained 10% drop that survives a cleaning cycle usually means a string is offline, a fuse has blown, or a module has developed a fault.

Seasonal checks

Before the monsoon, inspect structure bolts and earthing connections, confirm all cable entries and junction boxes are sealed, and clear roof drainage around the array so water does not pond under the structure. After the monsoon, look for corrosion at the structure base, check for moisture ingress in the DCDB and ACDB, and verify surge protection device indicators. In summer, ensure the inverter's ventilation is not obstructed and that it is not in direct afternoon sun.

Inverter care and common faults

The inverter is the component most likely to need attention over the system's life. Keep it in a shaded, dry, ventilated location and keep its vents free of dust and cobwebs. Common faults and their usual meanings: an insulation or isolation error typically points to moisture in a DC connector or a damaged cable; grid over-voltage errors are usually a supply-side issue in your area; a single low string points to shading, a blown fuse or a failed connector; a complete zero with a healthy grid usually means a tripped AC breaker.

• Do not open DC connectors or the DCDB yourself — DC arcs are dangerous
• Note the exact error code on the inverter display before calling support
• Keep the commissioning report and warranty documents accessible

Annual service checklist

Once a year, a technician should carry out a full preventive service. This is also the right moment to review a year of generation data against the design estimate and decide whether cleaning frequency needs to change.

• Visual module inspection for cracks, hotspots, delamination and snail trails
• Torque check on structure fasteners and module clamps
• Thermal check of DC and AC terminations for loose or heated joints
• Earthing resistance measurement and SPD condition check
• Inverter firmware, fan and filter check; error log review
• String-wise current and voltage measurement against the design values

What is covered by warranty

Modules generally carry a 10–12 year product warranty and a 25–30 year performance warranty. Inverters typically carry 5–10 years, extendable with some brands. Structures and workmanship are covered under the installer's own terms. Routine cleaning and consumables are not warranty items. Keeping cleaning records and monitoring data makes any performance claim far easier to support.