For a typical 2BHK Indian family: 150Ah provides 4–6 hours backup at moderate load. 200Ah provides 7–10 hours — enough to sleep through a night power cut without refilling. In states with 6–8 hour power cuts (UP, Bihar, Rajasthan, Odisha), always choose 200Ah minimum. In metro cities (Delhi, Mumbai, Bangalore) with 1–2 hour power cuts, 120–150Ah is sufficient. Always choose the larger battery if budget allows.

Luminous is India’s #1 inverter brand by sales — 25+ million homes, widest service network (3,500+ service centers), best resale value. Microtek is 30+ years old and stronger in smart/Wi-Fi inverters and Li-ion technology. For tier-2/3 cities: choose Luminous for service network. For urban apartments wanting smart features + Li-ion: choose Microtek iLithium. Both have excellent quality; Luminous has the edge on availability and service.

A 1.5 ton inverter AC requires 1300–1800W. Most home inverters (850–1100VA) cannot run an AC. To run a 1.5 ton AC on inverter: minimum 2KVA (2000VA) inverter required, with a 200Ah or preferably 150Ah×2 battery bank. The Microtek iLithium 1500W model can run a 1-ton AC but not a 1.5-ton. For AC backup, consider a dedicated solar inverter system — it’s more economical for long power cuts.

For lead-acid tubular batteries (Luminous, Okaya): summer (April–June) — check every 30–40 days. Winter — every 60–75 days. Rule: when electrolyte level drops below the “minimum” mark on the battery casing, top up with distilled water (not tap water). Never use RO purified water — use only commercially sold distilled water (₹15–20/litre at medical/auto shops). Li-ion batteries (Genus MaxiLion, Microtek) require zero water — ever.