VCL-2709, IEEE C37.94 to E1 Converter is a ruggedized, sub-station-hardened protocol converter that converts the IEEE C37.94 Interface to an E1 Interface to allow transmission of IEEE C37.94 over an E1 / SDH network

The VCL-2709 supports point-to-point applications.

professional modem dialup leased lineProvided high-precision clock recovery and clock re-generation functions which allows error free transmission of IEEE C37.94 channels over an E1 / SDH network.

The most common application for the VCL-2709 converter is for inter-connecting IEEE C37.94 Differential Protection Relays over an E1 / SDH network between two sub-stations.

By installing a VCL-2709 converter, the existing IEEE C37.94 interfaces from protection relays can be converted to and inter-connected over an E1 / SDH network without incurring large capex, or without the tiresome task of having to replace or rewire the IEEE C37.94 Relays which need to be interconnected to the far end substations over E1 (SDH) transmission links.

VCL-2709 is available in DIN Rail mount version as well as a 1U high, standard 19-inch rack mount version.

VCL-2709 can be used over E1 / SDH network as it is described in the following application diagram: 

Modem RTC liaison specialisee


C37.94 Interface Specifi­cations

  • Number of C37.94 interfaces : 1 (1Tx, 1 Rx)

  • Standards: IEEE C37.94 Optical connector: ST

  • Optical: 820nm/850nm Multi-Mode

Power Supply

  • Internal: 48V DC (input range 18V DC to 60V DC)

  • External Adapters: 110V DC, 220V DC, 100~240V AC


  • Number of ITU-T G.703 E1 (2.048 Mbit/s) interfaces: 1

  • Conformity: G.703

  • Connector: RJ45 (F) or BNC (F) depending of reference


 VCL-2709-DIN-ST-120-DC      IEEE C37.94 to E1 Converter DIN Rail Mount Version, RJ45 120 ohms,  DC Power supply