India's rooftop solar market has changed scale. The PM Surya Ghar: Muft Bijli Yojana, launched in February 2024 with a target of putting rooftop solar on one crore homes, has by mid-2026 reached more than 50 lakh households according to the Ministry of New and Renewable Energy, with about 14.8 GW of rooftop capacity commissioned. July 2026 alone saw a record 5.06 lakh installations, a pace of roughly sixteen thousand systems a day. The scheme offers a central subsidy of up to \u20b978,000 for eligible households, which is \u20b930,000 for a 1 kW system, \u20b960,000 for 2 kW and \u20b978,000 for 3 kW or more, and installations go through empanelled vendors.
For an installer, that volume means thousands of identical jobs, and each one has the same quiet requirement: protected cable routes on the roof and down the wall. Conduit is a small cost in a solar system and a large factor in how long that system lasts without trouble. This guide explains where conduit is used in a rooftop installation, which grade and size to choose, how to deal with sun and heat, how to plan bulk supply for a busy installer, and how Trity Pipes supports vendors.
Why conduit matters on a rooftop solar system
A rooftop system has a few cable runs, and each one faces a hard environment.
- DC string cables carry power from the panels to the inverter, and they run across the roof in full sun.
- AC cables carry power from the inverter to the distribution board and meter, usually down an exterior or interior wall.
- Earthing conductors connect the array, structure and inverter to the earth system.
- Communication and monitoring cables may run from the inverter to a router or logger.
Unprotected cable on a roof suffers UV damage, heat, moisture, rodent attack and mechanical damage from foot traffic and maintenance. Conduit encloses the cable and shields it from all of those, so the installation lasts as long as the panels. Our general guide on conduit pipe for solar panel wiring covers the principles, and this post focuses on the high-volume residential job.
Where conduit is used in a typical home installation
From the array to the inverter
DC cables are usually clipped along the panel frames and then routed to the inverter location. Where the run is exposed on the roof surface or along a parapet, conduit protects it.
Down the wall to the inverter and distribution board
The cable has to get from the roof to the inverter and from the inverter to the main distribution board, often through an exterior wall or shaft. Conduit gives a neat, protected route with proper bends and boxes.
Earthing and bonding
Earthing conductors should be protected where they are exposed to damage. Keep earth routes continuous and accessible for testing.
Entry points
Where cables enter the building, seal the conduit entry against water and insects.
Choosing grade and size for residential rooftop solar
For most home systems, the choices are simple.
- Grade: HMS grade is the usual recommendation for exposed rooftop and wall runs, because of the heat, sun and physical exposure. MMS can suit protected indoor sections.
- Size: 20mm or 25mm conduit usually suits the cable runs of a typical 1 kW to 5 kW home system. Larger systems or multiple strings may need 32mm. Check the cable diameter and number of cables for each run, and keep the fill comfortable so that cables can be pulled without damage. Use our conduit pipe size chart for guidance.
- Separate runs: keep DC and AC in separate conduits, and label them clearly.
Our LMS, MMS and HMS guide explains the grades.
Sun, heat and UV: what to check
A rooftop gets some of the strongest sun a conduit will ever see, and uPVC needs to be suited to it.
- UV stabilised compound resists the surface damage and brittleness that unprotected PVC develops under sustained sun. Ask the manufacturer to confirm in writing that the product line you are buying is formulated for outdoor exposure. Our guide on UV resistant conduit for outdoor wiring explains what to ask.
- Thermal expansion: a conduit run on a hot roof expands and contracts every day. Use saddles at proper spacing, avoid rigidly fixing every point on a long straight run, and add expansion couplers where a run is long.
- Heat near panels: keep conduit and cable clear of the hottest surfaces where possible, and follow the module and inverter manufacturers' instructions.
- Storage before use: keep pipe in shade, flat and supported until it is used, because stacks left in the sun can deform.
For Rajasthan, Gujarat and other high-sun regions, these points matter even more. Our regional guide on conduit pipe in Rajasthan covers desert conditions in more detail.
Fixing, sealing and finishing
Good workmanship is what separates an installation that lasts from one that fails in a few seasons.
- Cut the conduit square and remove burrs.
- Fix saddles at the spacing recommended, closer on exposed horizontal runs.
- Use sealed boxes and proper glands at changes of direction and at the inverter.
- Seal conduit ends against dust, water and insects.
- Avoid sharp bends that make cable pulling difficult.
- Label the runs for DC, AC and earth.
- Leave a drip loop where cable enters equipment, so that water does not run into it.
- Keep records and photographs of the installation for the commissioning file.
Our guide on common conduit pipe installation mistakes lists errors worth checking before handover.
The installer's business case for good conduit
Conduit is a small share of the cost of a system, and cutting corners on it saves very little. A cracked or sun-degraded conduit can expose DC cable, and a callback to a home costs the installer time, travel and reputation. When a vendor handles hundreds of installations, even a small callback rate becomes a large cost. Choosing a certified, consistent conduit once and using it across all jobs reduces that risk and simplifies purchasing.
Planning bulk supply for a busy installer
Installers and EPC vendors working under the scheme buy conduit in volume, and a few habits help.
- Standardise on a few sizes and grades, such as 20mm and 25mm HMS, so that stock is easy to manage
- Buy fittings with the pipe, including bends, couplers, junction boxes and saddles, in matching sizes
- Order in single batches where possible, so that finish and dimensions are consistent
- Plan monthly volumes with your supplier, and ask about rate validity and phased delivery. Our guide on buying conduit pipe in bulk explains how to structure an enquiry
- Keep certification documents for your files, since some projects and financing partners ask for them
Opportunity for dealers who serve solar installers
Solar installers in every district buy conduit, boxes and saddles from local suppliers. A hardware or electrical dealer who stocks the right sizes in HMS grade, with fittings and fast delivery, can become the first call for local vendors. Our guide on how to sell conduit pipe as a dealer shows how to win repeat orders, and our guide on becoming a Trity Pipes dealer explains how to apply.
Why installers and dealers choose Trity Pipes
Trity Pipes is a manufacturer of uPVC conduit pipes and fittings made from lead-free, high-grade virgin raw materials, certified to IS 9537 Part 3 with ISO certification. For rooftop solar vendors, we offer:
- LMS, MMS and HMS grades with matching fittings from one manufacturer
- Technical guidance on grade and sizing for rooftop runs. For exposed solar work, ask our team to confirm the grade and specification suited to your site
- Bulk and phased quotations with the rate validity stated
- Certification documents on request, available on our certifications page
- A Delhi NCR factory with dispatch to 20-plus states, and a network of more than 250 distributors and 1,500 dealers
See the uPVC conduit pipes and fittings range and ask our team for the Trity Pipes price list for your monthly requirement.
A standard conduit kit for a 3 kW home system
Many installers save time by defining a standard kit for the most common system size. A typical 3 kW residential job might need a length of 20mm or 25mm HMS conduit for the roof run and wall run, a handful of bends and couplers, junction or inspection boxes at the turns, saddles at the right spacing, end caps and glands for the inverter entry, and a short separate run for earthing. The exact quantities depend on the distance from the array to the inverter and the distribution board, so measure a few typical jobs, build a kit list and order to it. A standard kit reduces site waste, shortens preparation time and makes stock easy to count.
Working with Trity Pipes as a vendor or dealer
Installers who work under the scheme tell us that they want three things from a conduit supplier: consistent product, reliable delivery and a quick answer when they ask a question. Trity Pipes makes conduit and fittings in our own plant, so one call covers sizes, grades and delivery. Share your monthly volume and typical kit, and we will prepare a quotation and a delivery plan. Dealers who serve solar vendors in their district can also ask about stocking a standard solar kit, and our team can help you work out what to hold.
Frequently Asked Questions
Which conduit is best for rooftop solar cables?
HMS grade, with UV stabilised compound for exposed runs, is the usual recommendation for rooftop and exterior wall runs. Confirm the UV rating with the manufacturer.
What conduit size should I use for a home solar system?
20mm or 25mm usually suits the cable runs of a typical 1 kW to 5 kW home system, with 32mm for larger systems or several cables. Check cable diameter and fill for each run.
Should DC and AC cables share a conduit?
Keep them in separate conduits and label them clearly, so that maintenance is safe and faults are easy to trace.
Does PM Surya Ghar require a specific conduit?
The scheme sets requirements for modules and system components through its guidelines and empanelled vendors. For conduit, follow your project specification and installation standards, and use certified material. Check current scheme guidelines with your DISCOM and vendor documentation.
Can Trity Pipes supply conduit in bulk to solar installers?
Yes. Share your monthly volume, sizes and grades, and our team will prepare a quotation and discuss phased delivery from our Delhi NCR factory to your state.
How can a dealer start supplying solar installers with Trity Pipes?
Apply through the Become a Distributor form on our website. We will discuss your territory, range and volumes, and how to stock the sizes that installers use most.
Supplying rooftop solar installers? Contact Trity Pipes on +91-9821030072 or +91-9319984755 for a bulk quotation, certification documents and a standard conduit kit for ISO-certified uPVC conduit pipe from our Delhi NCR factory.