For the 20kW inverter, we recommend 6 to 47 panels of 640–650W each (32 panels = 20.48 kW DC). A common question is whether 6 panels is enough — for a 20kW inverter, 6 panels (≈3.84 kW DC) significantly underutilises the inverter and reduces your daily generation. Our design tool at my.saigal.us calculates the exact right count for your specific loads and roof.
Knox hybrid inverters include the anti-islanding protection relay required by NEPRA. Note: NEPRA cancelled the net metering policy in 2026 and replaced it with net billing. We assist with the net billing application to your DISCO (FESCO, LESCO, IESCO, etc.) as part of our installation service. Processing time is typically 30–60 days after installation.
A standard residential installation (10–16 panels, inverter, 1–2 batteries) takes 4 to 6 days. Day 1: Order materials. Day 2: Materials delivery. Day 3: Panel mounting structure and panel installation. Day 4: DC/AC wiring, inverter and battery commissioning, earthing, testing, and app setup. Your system is fully operational by end of Day 4.
Saigal Solar provides a complete 3-pit earthing system with every installation, using separate dedicated earth pits for AC, DC, and lightning protection.
DC Earthing: All panel frames bonded with 4mm² copper earth wire. DC surge protection devices (SPDs) are installed per string, with a dedicated copper conductor running to a separate DC earth pit filled with damp sand.
AC Earthing: AC surge protection device (SPD) installed in the DB box. Dedicated copper conductor from the inverter earth terminal to a separate AC earth pit. Earth resistance tested and documented below 5 ohms at commissioning.
Lightning Arrestor: A lightning arrestor rod is installed at the highest point on the roof. A dedicated cable runs from the rod down to its own separate earth pit — fully isolated from the AC and DC earth systems.
We use 4mm² or 6mm² pure copper DC cables and 4mm² & 6mm² copper AC cables throughout — no aluminium, no undersized wire. Mounting structures are heavy-duty galvanised iron (GI) C-channel, the same grade used in commercial installations. All roof fasteners are also galvanised. The structure is engineered for Pakistan's wind loads.
Most inverters come with a 5 years product warranty. As an authorised dealer, Saigal Solar handles all warranty claims for you — you do not need to ship the unit abroad. Extended warranty options are available; ask us at the time of purchase.