Data at light load & solar noon
Harvesting operating power from ≥1 A (vs ~5 A for comparable devices) keeps monitoring active during mid-day solar feed suppression and off-peak night cycles — preserving baseline trend lines.
India · Self-Powered Wireless Thermal Monitoring
VTI self-powered sensors harvest energy from just ≥1 A of primary conductor current — maintaining continuous thermal tracking across lightly loaded feeders, night valleys, and heavy summer peaks. Type-tested to 500 kV (partial discharge 8.7 pC, lightning impulse −1500 kV) for switchgear busbars, transformer bushings, and EHV substations across India.
Why VTI for India
Harvesting operating power from ≥1 A (vs ~5 A for comparable devices) keeps monitoring active during mid-day solar feed suppression and off-peak night cycles — preserving baseline trend lines.
Type-tested to 500 kV with partial discharge of 8.7 pC (acceptance < 10 pC) and −1500 kV impulse withstand at independent high-voltage laboratories — proven for 132 kV, 220 kV, and 400 kV Indian switchyards.
Current-transformer induction eliminates batteries entirely. No recurring shutdowns or maintenance trips to swap cells across thousands of switchgear panels and transformer bushings.
Compliance & international references
Mapped against global continuous thermal monitoring guides and transparently documented for utility technical tenders.
Clause-by-clause mapping to the IEEE guide for continuous thermal monitoring of switchgear and MCCs up to 52 kV. Review our full compliance matrix →
CIGRE Working Group B3.D2.62 identifies energy harvesting thermal sensors as the recommended mitigation technology for transformer and circuit-breaker thermal risks.
The GW22 / GW22-D gateway integrates seamlessly with substation automation systems via Modbus TCP, MQTT over TLS, and IEC 60870-5-104. (IEC 61850 is on the roadmap.)
Wireless transmission operates in license-free bands: LoRa IN865 (865–867 MHz per WPC GSR 564(E) rules) and 2.4 GHz BLE, with low duty cycles suitable for dense substation environments.
Figures below are taken directly from the VTI-TS-22, VTI-TS-26 and GW22-D datasheets (single source of truth).
| Sensor — VTI-TS-22 & VTI-TS-26 | Specification |
|---|---|
| Power supply | Current-transformer energy harvesting, 100% battery-free |
| Self-powered start current | ≥ 1 A primary load current (harvested directly from the conductor) |
| Accuracy | ±0.2 °C (within −10 to +65 °C); ±0.5 °C over the rest of the range |
| Measurement range | −40 to +125 °C |
| Operating temperature | −40 to +85 °C · humidity 0–100% |
| Type-tested voltage | Up to 500 kV (partial discharge 8.7 pC, lightning impulse −1500 kV) |
| Wireless — VTI-TS-22 | BLE 2.4 GHz, EIRP 6 dBm, approx. 100 m |
| Wireless — VTI-TS-26 | LoRa IN865 band (865–867 MHz), up to 3 km line of sight |
| Reporting interval | Adaptive, 5–30 min (faster as temperature changes) |
| Mounting | Magnetic straps + stainless-steel ties; installed with the circuit isolated, earthed and proved dead |
| Product names | VTI-TS series, previously catalogued as the TBR22 series |
| Gateway — GW22-D | Specification |
|---|---|
| Architecture | Receive-only listening hub (does not interfere with the transmission system) |
| Wireless | Dual-band 2.4 GHz (BLE) + LoRa IN865 |
| Capacity | Up to 1,000 sensors per gateway |
| Network & protocols | RJ45 Ethernet 10/100 · Modbus TCP, MQTT over TLS, IEC 60870-5-104 → SCADA / DCS / Cloud |
| Power | 220 V AC/DC universal substation auxiliary supply |
| Form factor | 93 × 84 × 24 mm, 200 g, DIN-rail / wall mount · −40 to +85 °C |
Note: SCADA integration is via Modbus TCP, MQTT over TLS or IEC 60870-5-104. IEC 61850 is currently on the development roadmap. In India, LoRa frequencies are set to the WPC-de-licensed 865–867 MHz band.
Share your substation, feeder, or switchgear project details. VTI Corp and our Indian partner Pragnanexgen will provide the technical datasheet, IEEE/CIGRE mapping documents, and trial deployment proposals.
Indian partner: Pragnanexgen · Technical representation & local project support across India.