Located in Pickering, Ontario, Trench Limited’s Instrument Transformer Division (ITD) is the leading manufacturer of oil insulated instrument transformers for voltage and current measurement. All products are designed to the highest standards of high accuracy revenue metering and protection applications, and also conforms to all ANSI/IEEE, CSA and IEC requirements. The new instrument transformer factory is sprawled over , sq ft (, sq meter) and includes a manufacturing plant, a -storey office and world-class R&D facilities. With a strong market position in North America and global reputation on many world markets, Trench Canada is one of the leading factories worldwide for instrument transformers.

The company was founded in in Switzerland by Emil Haefely, an inventor who played a decisive role in the development of the electrotechnical industry at beginning of the th century. With the patent of the OIP Condenser type bushing in by Emil Haefely, the company became a pioneer in Oil type bushings. Trench France is part of the Trench & HSP Bushing group belonging to Siemens with locations in France (Trench France), Germany (HSP) and China (THVS). This close cooperation for innovation and design is supported by Siemens process and manufacturing know how. In , the Trench Group decided for Trench France to focus specifically on bushings by making extensive manufacturing investments and improving all customer relevant processes.

Siemens Limited, launched manufacturing of High Voltage Instrument transformers in , in the existing HV products factory at Aurangabad in India. The state-of-the-art facility is producing CVTs with Oil insulation and CT/PTs with SF insulation and is the only factory in India manufacturing SF CT/PTs with Composite insulators with technology support by Trench Germany. The factory also supplies GIS components (Instrument Transformers and Bushings) and Grading Caps to Siemens India. With a total area of Sq. Meters, Siemens Instrument Transformers is the market leader for CVTs in the domestic market. For SF CT/VTs, the facility has its own set up of Composite insulators. There are some key utilities/ industries from Power Generation in India, who have completely switched their CT/PT requirements to SF technology. Siemens India is also working continuously together with Global R&D on new generation and digitalized products to serve the customers with advancements further.

Trench Germany, the former MWB Messwandler-Bau &#; founded in &#; is located in the world-heritage city Bamberg. Based on the long-time experience with the production of high voltage equipment with epoxy-resin and oil-paper insulation, the company pioneered the design and production of gas insulated instrument transformers and developed in the first GIS SF insulated voltage transformer for encapsulated switchgear (GIS). In Trench Germany completed its kV portfolio in supplying the first kV combined current and voltage instrument transformer for outdoor installation (AIS). Today it is the competence center for gas insulated equipment in the Trench Group and offers plant and office space totaling . m². With the introduction of SF free instrument transformers with Clean Air insulation, Trench Germany once again demonstrates its technological leadership for gas insulated equipment.