Medha works in association with Metro owners, operators and local coach builders to study, design and supply advanced traction system for building new metro trains and/ or for revival or renewal of existing fleet of old metro cars.

Solutions are designed to suit available input power supply, vehicle design and operational requirements. Revival of existing fleet can be done in shorter duration and at very economical costs. Association also offers opportunities for building technological capacities and capabilities within the country of implementation.

Communication and Interfaces

Train-wide control network with redundant Multi-function Vehicle Bus (MVB) and Wired Train Bus (WTB) or redundant Ethernet Consist Network (ECN) and  Ethernet Train backbone (ETB) between control systems of TCMS as per IEC 61375.

Test Modes

Centralized auto and manual test modes, including brake test, auto test for relays,  brake chopper test, lights test, manual test of inputs and outputs for entire train control equipment.

Safety Features

All power equipment are continuously diagnosed for its protection such as traction converters/ auxiliary converter input over voltage, input over current, load side earth fault and short circuit protection. 

Extensive Fault Diagnostics

Over 500 types of faults covering more than 700 parameters. Fault and event storage for 100 days. Centralized configuration and downloading of faults, events and status data.  

Kolkata Metro

Basic unit: 1 DTC +1  MC

Train consist: 2/3/4 basic units or 4/6/8 cars respectively

Max. speed: 90 kmph

Average acceleration (0-40 kmph): 0.85 m/s²

Average deceleration : 1.1 m/s²

• Passenger capacity (8 car consist): 400 seating, 3120 standing
• Traction converter: 2 units per basic unit, 435 kW per unit, underframe mounted, IGBT based control and forced air cooled, 32 bit DSP based traction computers, bogie level control
• Auxiliary Converters: 162 kVA, 415 V     3φ 50 Hz, 110 V dc
• AC traction motors: 204 kW, 3000 rpm, fully suspended
• Controls: microprocessor based TCMS with dual redundant ECN/ ETB communication network
• Driver desk: driver control interface with 10.4” touch based TFT, switches/ push buttons and master controller
• Battery bank: 96 V dc , 300 AH per basic unit
• Passenger information system: 17.5” TFT based in-coach display with audio announcements