Single-Line Diagram — Incomer, Panel, Metering & Temperature Points

Secure Meters Elite 440 (E440-34-4-1-0-2-1-0)

Sensor: Rishabh ESCT 100/150, 2000/5A, Class 0.5S split-core CT

Replicates utility billing logic; triggers a pre-alarm before the 950 kVA contract limit is crossed

Panel-door flush mount, 92×92mm cutout

A — Optris CTratio 2M / CSvision R1M (two-colour/ratio): 550–3500°C, robust to smoke, dust, slag and dirty optics. Same vendor family as elsewhere in this spec, shared spares/support. Sold in India through Optris's distribution (e.g. Manglam Electricals lists the Optris ratio/two-colour line). Higher upfront cost.

B — Tempsens A250C (two-colour, Indian-made): Udaipur manufacturer — local service and shorter lead time, typically lower cost. Listed range 350–1350°C; confirm with Tempsens whether a higher-range variant covers the 1610°C tap before ordering.

Sighted directly on the furnace bath — independent of Meter 2, which only measures the electrical feed.

The ladle is portable — a fixed sensor doesn't work. Pointing/dipping is done manually by the operator, so lower accuracy than the furnace sensor is acceptable here.

Neither option below has a record/capture output — the operator reads the value and logs it by hand. Not wired to the RS-485 bus, not captured in the EMS.

A — Handheld single-wavelength IR thermometer (e.g. Optris CT 1M used handheld, or any industrial IR gun — HTC, Kusam Meco, Testo, Fluke all sell locally): lowest cost, simplest, walk-up-and-read at preheat/tap. Emissivity/smoke affect accuracy, which is acceptable for this manual use.

B — Disposable immersion (dip) thermocouple + handheld lance (Heraeus Electro-Nite or equivalent — the established global standard for steel tap temperature, used worldwide): contact measurement, more accurate, not fooled by emissivity or smoke; ongoing per-use consumable tip cost.

Recorded power factor 0.91 · 600A max input @415V

Tap temperature 1610°C · ladle preheat 900°C (existing process control points)

Meter 2 (electrical) + both temperature sensors (thermal) instrument this stage independently.

Phase 3 (planned): this load — and the ladle heater — will be switchable via the EMS Server → IoT Gateway(s) → relay/actuator control path. Relay/actuator hardware not yet installed.

Polls Meters 1–3 and the furnace temperature point over RS-485 Modbus RTU (the field bus) — see the bus drawing above: every networked device drops onto the same shared trunk, the Gateway isn't wired to just one of them.

The ladle reading is manual (see that block) — neither candidate device has a record/capture output, so it isn't on this bus and doesn't reach the EMS automatically.

One or more Gateways may be deployed depending on device count and physical layout; each covers a subset of the networked devices.

Forwards the aggregated data to the on-premise EMS Server over Ethernet/TCP.

Phase 3 (planned): will also carry switching commands back down from the server to furnace/ladle relays — not yet implemented.

Hosts the demand pre-alarm, SEC tracking, and dashboards. Current scope is monitoring only.

Phase 3 (planned): will issue furnace/ladle heater switching commands back through the IoT Gateway(s) to relay/actuator hardware at each load (blueprint Sections 11–12 control logic) — control loop not yet implemented.