Instrument transformers, LV to EHV.

Inductive current transformers for metering and protection duty across every voltage tier. Cast-resin variants for LV (slip-on, wound primary, split-core cable, ring core, window type) and MV (indoor support-type, outdoor support-type, cable-type, generator CTs, and CTs for gas-insulated switchgear) up to 52 kV. Oil-paper and gas-insulated variants for MV outdoor duty, HV, and EHV up to 550 kV, engineered as free-standing outdoor apparatus.

Inductive voltage transformers for metering and protection across LV, MV, and HV. Cast-resin LV panel-mounted units, MV indoor VTs (earthed and unearthed), MV metal-clad VTs, and MV outdoor VTs up to 52 kV. Oil-paper and gas-insulated free-standing outdoor VTs for MV, HV, and EHV where the site requires oil-immersed or gas-insulated apparatus.

Combined CT and VT in a single tank for HV and EHV outdoor substations, reducing footprint, foundations, and installed cost.

Coupling capacitor voltage transformers for EHV outdoor substations, up to 550 kV. Combined voltage measurement and power line carrier (PLC) coupling function, with matched line trap coupling for wideband PLC systems.

HV voltage transformers rated to deliver auxiliary station power in addition to the standard metering and protection burden, dispensing with a separate auxiliary transformer at remote or unmanned substations.

Low-power current transformers (LPCT), Rogowski coils, and low-power voltage sensors to IEC 61869-6, with merging unit interfaces for IEC 61850-9-2 process bus. Supplied for MV switchgear, ring main units, and digital substation projects.

Grounding and phase-protection transformers, metal-clad VTs for switchgear compartments, three-phase CTs, generator neutral CTs, and application-specific custom builds engineered around the site requirement.

Precision magnetic materials, controlled turns ratio, and calibrated burden ranges deliver Class 0.1 and 0.2S revenue metering accuracy for utility billing points. Protection cores are engineered with low-leakage-flux design principles (ring cores with evenly distributed secondary windings and a short primary conductor) for accurate transient reproduction and reliable relay operation during fault conditions. Low remanence, defined accuracy limit factor (ALF), and specified knee-point voltage matched to numerical protection relays, differential schemes, and busbar protection.

Oil-paper and gas-insulated designs verified through full lightning impulse withstand, chopped-wave impulse, and power-frequency withstand testing. HV and EHV oil-paper units engineered for controlled dissipation factor (tan δ) at operating temperature for thermal stability at high voltage, with oil quality tightly controlled through drying and degassing during impregnation. Multiple chopped impulse (MCI) type tests validate switching-surge withstand in modern GIS-connected networks. Cast-resin MV units qualified for partial discharge performance at rated voltage.

MV voltage transformers designed with ferroresonance damping to remain stable on lightly loaded networks and circuits with circuit-breaker grading capacitance. Capacitive-discharge withstand for VTs applied on cable-fed systems, capacitor bank circuits, and GIS-connected substations, verified through dedicated energy-discharge testing.

Free-standing HV and EHV instrument transformers engineered with pressure relief and secondary containment features to control the consequences of internal arcing faults, protecting adjacent primary plant and station personnel.

Oil leaks, gas leaks, and moisture ingress are among the most common causes of long-term instrument transformer degradation in service. Oil-paper units use metallic bellows or nitrogen-cushioned expansion systems to maintain positive internal pressure across the full ambient temperature range, blocking moisture ingress and oil oxidation. Gas-insulated units use metal-to-metal sealing surfaces with double O-ring geometry engineered for lifelong gas retention. Cast-resin MV units are inherently sealed by construction. Sealing performance is verified through pressure, tightness, and leakage tests at manufacture.

Outdoor cast-resin CTs and VTs qualified for direct outdoor installation at MV, with hydrophobic surface treatment and creepage distance dimensioned for coastal and industrial environments. Oil-paper and gas-insulated HV and EHV free-standing units available with composite polymer insulator housings and silicone rubber sheds for coastal, industrial, and high-pollution environments, in place of porcelain. Seismic qualification to IEEE 693 and AS/NZS 1170 where the project requires it.

Where available from the manufacturer's current range, SF6-free gas-insulated instrument transformers are offered for HV outdoor duty, in line with utility SF6 phase-out programmes.