ESIM
ESIM srl, formally Elettrica Società Impianti Meridionali, is an Italian supplier of railway diagnostic systems, signalling installations and electric traction equipment, headquartered in Bari and active on the Italian network as well as in export markets in Asia.
ESIM was founded in 1989 by Domenico Santoro, initially working in railway signalling and electrical traction installations. A dedicated railway diagnostics department followed in 2007, set up to design and build sensor and measurement systems for infrastructure and rolling stock.
Core products and services
ESIM’s track geometry measurement work centres on OpERA (Opto Electronic Railway Analysis), developed in 2008 to record track geometry parameters automatically.
Company documentation describes an onboard subsystem that captures line geometry using laser profilometry and an inertial measurement unit, with OpERA synchronising and processing the readings. Spatial reference comes from fixed recalibration points along the track, and the processed data is transferred to a ground-based data centre for analysis.
Beyond track geometry, the portfolio covers rail temperature monitoring, unmanned infrastructure inspection, overhead line geometry and wear measurement under the SAGU designation, and pantograph condition assessment under the Panto 3D-S line.
Market position
Rete Ferroviaria Italiana (RFI) is a core customer. ESIM holds RFI qualification certificates for signalling, electric traction and tunnel emergency systems, and has supplied an unmanned diagnostic system covering the Sardinian network of roughly 450 km. Its published reference list adds Trenitalia, Italferr, Trenord, FerrovieNord, Ferrotramviaria, Ferrovie del Sud Est and Ferrovie Emilia-Romagna, spanning both the national network and Italy’s concession railways.
Work outside diagnostics remains substantial, including signalling maintenance and ERTMS design and construction on lines funded under Italy’s national recovery and resilience plan.
ESIM srl is an unlisted limited company with registered share capital of EUR 572,500, fully paid up. It states that its diagnostics department has filed several patents on its measurement systems; individual patent numbers are not published.
Current activity
The unmanned diagnostic systems, which remove the need for operators on inspection runs, have been supplied outside Italy — to Taiwan Railway, to the Ningbo metro network in China, and, in the SAGU overhead line configuration, to Mumbai Metro in India.
Alongside Bari and an office in Rome, ESIM has offices in Spain and Serbia. Hardware, software and mechanical development sit within the same division, which lets the company specify a measurement chain from sensor to data output rather than integrating externally sourced subsystems.
