What is a smart meter in simple terms?

A smart meter is a digital electricity meter that records consumption at short intervals (commonly 15 or 30 minutes) and sends that data automatically over a communication link, to the utility or to a cloud platform. A traditional meter only accumulates total kWh and has to be read by hand.

What is the difference between a smart meter and AMI?

The smart meter is the device. AMI (Advanced Metering Infrastructure) is the whole utility system around it: meters, communication network, head-end system (HES) and meter data management system (MDMS). Private sub-metering inside a factory or building usually skips the HES/MDMS layers and sends data straight to a cloud dashboard or BMS.

Is a utility smart meter the same as a sub-meter?

No. A utility smart meter is the DISCOM's billing meter at your supply point, built to IS 16444 and installed and owned under the utility's metering rules. A behind-the-meter sub-meter, such as Tech OVN's Titan, is installed by the site owner inside their own panels to see where energy goes circuit by circuit. It does not replace or interfere with the utility meter.

Can a smart meter measure rooftop solar export for net metering?

Yes. Utility smart and static meters that measure import and export can serve as the net meter where the DISCOM approves them. Tech OVN's utility smart and static meters are dual-purpose and support net metering. A behind-the-meter monitor such as Titan can track solar generation and site consumption alongside the DISCOM's net meter, but it is not the billing net meter.

Which accuracy class does a smart meter need?

Accuracy classes are defined by IEC standards: Class 1 and 2 in IEC 62053-21, and Class 0.5S and 0.2S in IEC 62053-22. Which class applies to a billing meter is set by the CEA metering regulations according to the connection voltage; for example, meters up to 650 V are Class 1.0 or better. For behind-the-meter sub-metering, Class 0.5S is a common choice for cost allocation. Tech OVN's utility meters are Class 1; Titan is Class 0.5S.

Who can see my smart meter data?

Your DISCOM collects the data it needs from its own billing meter. Personal data handling in India is governed by the Digital Personal Data Protection Act, 2023, whose rules were notified in November 2025 with most obligations phased in over 18 months. For a private sub-meter on your own premises, the data belongs to the site owner and is not sent to the utility.

Do smart meters work during a power cut?

Many utility smart meters send a last-gasp outage notification and a power-restore notification, which lets the DISCOM detect outages without customer calls. They do not measure during the outage, because there is nothing flowing to measure.

Can a smart meter work without internet?

Yes. The meter keeps measuring and storing data locally; communication is only needed to move that data. Behind-the-meter meters can also be read locally over RS485 (Modbus RTU) by a BMS, SCADA or PLC without any internet connection.

What is a Smart Meter and How Does it Benefit You?

A smart meter is an electronic electricity meter that records consumption at short intervals, commonly every 15 or 30 minutes, stores it with a timestamp, and sends it over a communication link to the utility or to a cloud platform. A traditional meter only counts total kilowatt-hours and has to be read by a person. That difference, interval data plus communication, is what makes a meter “smart”.

How a smart meter works

Every smart meter has four functional blocks. A measurement front end senses voltage and current, through a shunt on direct-connected meters or through current transformers (CTs) on larger supplies. A metrology engine calculates active, reactive and apparent power and energy from those samples. A microcontroller keeps time, stores interval data, applies tariff registers and logs events. A communication module (RF, cellular, Wi-Fi, Ethernet or RS485) moves the data out. The meter sends computed values such as interval energy, demand and events, not raw waveforms.

Compared with a traditional meter, this gives you interval data instead of one monthly number, automatic reading instead of manual visits, support for time-of-day tariffs through multiple registers, import and export measurement for rooftop solar, and event records such as outages and tamper attempts.

Two different jobs: utility meters and sub-meters

“Smart meter” is used for two quite different devices, and mixing them up causes most of the confusion.

Utility smart meters sit at the supply point and are the basis of your electricity bill. In India they are built to IS 16444 and installed under the DISCOM’s metering rules, often with prepaid functionality. Our utility smart meter (IS 16444) and static meter (IS 13779) are in this category. Both are dual-purpose: they measure import and export and support net metering for rooftop solar.
Behind-the-meter sub-meters are installed by the site owner inside their own panels to see which feeders, machines, floors or tenants use the energy. They do not bill you and need no DISCOM approval. Tech OVN’s Titan is a Class 0.5S (IEC 62053-22) DIN-rail sub-meter for commercial and industrial sites, with external CTs from 100 A to 1000 A, Wi-Fi, Ethernet and RS485, and Modbus, MQTT and BACnet support. Read more on sub-metering for business.

A factory or building usually has both: one utility meter that the DISCOM bills from, and several sub-meters that the facility team uses to manage energy.

India’s smart meter rollout (RDSS)

Utility smart metering in India is being funded mainly through the Revamped Distribution Sector Scheme (RDSS). Under RDSS, smart metering has been sanctioned for 45 distribution utilities in 28 States/UTs, covering 19.79 crore consumers, 52.53 lakh distribution transformers and 2.05 lakh feeders (about 20.33 crore meters in all). As of 31 December 2025, 3.90 crore smart meters had been installed under the scheme, and 5.28 crore across all schemes, according to the Ministry of Power (PIB, 2 February 2026). A later parliamentary reply put RDSS installations at 5.73 crore as of 30 June 2026 (T&D India report). The installation deadline is the end of the scheme period, March 2028 (Lok Sabha reply, 31 July 2025).

One of RDSS’s aims is to cut distribution losses. National AT&C (aggregate technical and commercial) losses fell to 15.04% in FY 2024-25, from 22.62% in FY 2013-14 (Ministry of Power, PIB). The ministry attributes this to several reforms, smart metering among them. RDSS is a separate programme from the National Smart Grid Mission (NSGM), which supports smart grid planning and projects more broadly; smart meter funding figures belong to RDSS.

Benefits, without the hype

For consumers, a utility smart meter means bills based on actual readings rather than estimates, consumption data through the DISCOM’s app or portal, and access to time-of-day tariffs where the state offers them. Prepaid meters also let households track their balance.

For DISCOMs, they bring remote reading, remote connect and disconnect, outage detection, tamper and theft alerts, and energy accounting at the transformer and feeder level, which helps locate losses.

For commercial and industrial sites, the bigger value usually comes from sub-meters: allocating cost to departments or tenants, watching maximum demand and power factor before they turn into penalties, and checking whether an efficiency project actually delivered. How much that is worth depends entirely on the site, so we don’t quote a headline figure. If you want to estimate it for your own site, the energy audit ROI calculator lets you plug in your own numbers.

Accuracy classes: who decides what

The accuracy classes themselves are defined by IEC standards: Class 1 and Class 2 in IEC 62053-21, and Class 0.5S and 0.2S in IEC 62053-22. Which class a billing meter must meet in India is set by the CEA (Installation and Operation of Meters) Regulations according to connection voltage: up to 650 V, Class 1.0 or better; above 650 V and up to 33 kV, Class 0.5S or better; above 33 kV, Class 0.2S (as quoted in the OERC supply code; check the latest CEA amendments at cea.nic.in). Behind-the-meter sub-meters are not billing meters, so the choice is yours; Class 0.5S is common where readings are used to allocate cost.

Data privacy and security

Interval data can reveal when a home is occupied or when a plant is running, so privacy matters. The operative law for personal data in India is the Digital Personal Data Protection Act, 2023, with its rules notified in November 2025 and most obligations phasing in over the following 18 months. For a private sub-meter, the site owner controls the data. Whatever you deploy, look for encrypted transport (TLS for MQTT and HTTPS), signed firmware updates and role-based access to configuration.

Choosing a meter

If you are a DISCOM or an AMI integrator, the meter is specified by tender: see our AMI system page. If you run a factory, building or campus and want to see where energy goes, you need a behind-the-meter sub-meter: check the accuracy class, CT range and type (solid-core or split-core for retrofits), voltage range, and whether it speaks the protocols your BMS or cloud uses (Modbus RTU/TCP, MQTT, BACnet).