Delhi Metro Project completed

Up gradation of Master Clocks at OCC MB and BCC SHPK along with some Sub-master clocks at Station level for implementation of integrated OCC & BCC.

Developing a master clock solution that can synchronize clocks from multiple vendors can indeed be a challenging task. However, with careful planning and coordination, it was possible to achieve compatibility and integration among these different systems.

  • Requirement Analysis: Understanding the specific synchronization requirements of DMRC and the capabilities of the clocks provided by Westerstrand, MOBATIME, and Gorgy Timing. Also, by determining the common protocols, interfaces, and synchronization methods supported by these vendors.
  • Design and Architecture: Designing a master clock system that acts as a central clock system to synchronize the station sub-master clocks and then synchronization from sub-master clocks to existing station display clocks from different vendors. The master clock & Sub-master clock should be capable of handling multiple protocols and interfaces to communicate with each vendor's clock systems.
  • Protocol Integration: Develop or utilize existing protocols that are compatible with the clock systems of all three vendors. This may involve implementing or adapting industry-standard protocols such as Network Time Protocol (NTP), DCF, DCF-IMP, MOBALine & IRIG-B/AFNOR to ensure synchronization across vendors.
  • Deployment and Maintenance: Once the solution has been successfully tested, deploy it within DMRC's metro rail network. Provide ongoing maintenance and support to address any issues that may arise and ensure continuous synchronization and performance.

It's worth noting that the development of such a solution would require collaboration between the master clock solution provider and the clock vendors themselves. Close cooperation and open communication would be essential to overcome compatibility and integration challenges and provide DELHI METRO RAIL CORPORATION with a comprehensive working solution.


To cater DMRC requirements, MOBATIME India Pvt. Ltd. Together with its parent company Moser-Baer AG proposed GNSS based redundant Master Clock System (DTS 4160.grandmaster) compliant with ITU-T Recommendations G.811for time characteristics and requirements that shall serve as a Primary Reference Clock (PRC) equipped with OCXO oscillator having accuracy better than 3.0x10-10/day.

  • The two redundant Master Clocks has been designed in such a way that failure of one of the GNSS source shall not impact the synchronization, as Grandmaster A (TDS A) shall receive precise synchronization pulses from Grandmaster B (TDS B) over the redundant link.
  • The design construction and reliability of equipment is based on modern technology and standards using commercially available solid-state components.
  • The Master Clock DTS 4160.grandmaster proposed in this project is a high-performance NTP server
  • At Station level, Sub-Master Clock DTS 4803.masterclock (newly developed device) has been installed, which is equipped with MOBALine, IRIG/AFNOR outputs, serial RS 232/RS 485 interfaces with script file programmable telegrams, DCF/DCF-IMP or high accurate pulse/frequency outputs (RS 422 and optocoupler) and one additional DCF current loop output for Slave Clock Units with future reference.
  • This Sub-Master Clock DTS 4803.masterclock is taking time synchronization from OCC/BCC master clock over NTP and parallelly synchronizing existing slave display clocks at stations.
  • GUI-based MOBA-NMS at OCC-MB & BCC-SHPK to show the Status of all Master clocks & Sub-Master Clocks of all locations. The alarm shall be tracked up to the equipment level through various user-friendly screens.

Implementation & challenges to meet project milestone

After receiving the letter of award, the project milestone becomes the primary focus, and successfully achieving it requires careful planning and execution. Meeting project milestones within the designated timeline is always challenging and assigning the right resources at the right time is also crucial.

MOBATIME being an 85-year-old company, having expertise in time & frequency synchronization solutions, time distribution, time references and time displays took the challenge and completed the project within milestone deadline.

Work Execution Plan

  • January 11, 2023

    DMRC LoA Issue Date

  • May 11, 2023

    Material delivery at Metro Bhawan Delhi

  • June 11, 2023

    Installation, Commissioning & Testing of Master Clock at OCC & BCC including Sub-Master Clock at 44 stations

  • July 9, 2023

    Document submission for third milestone certificate and taking over certificate

LOA Issue Date: 11.01.2023