DM820. Compact SDH Mux.
Compact SDH Mux

The DM820 is a new generation compact SDH multiplexer with 2Mbit/s, 34/45Mbit/s, Ethernet/Gigabit Ethernet and SDH up to STM-16 support. With a fully modular platform, DS0 cross-connect, MPU redundancy, multiservice functionalities and operates with multiple rings and point-to-point links.


The DM820 platform is fully flexible, providing 2 slots for compact Main Processing Units (MPU), 2 slots for interface cards compatible with the DM800 series, 2 slots for power supply, 2 slots for specific interface cards and 2 slots for ventilation modules. All cards can operate in redundancy, increasing reliability and network availability.

  • Shelf of 2U high, compatible with standard 19" racks
  • Attend since E1 to STM-16 applications
  • Support to Ethernet NG-SDH interface modules
  • MSP, SNCP, MS-SPRing and DNI protection
  • MPU redundancy
  • Integrated fan module
  • Hot-swap on all modules
  • -48/60VDC Power supply redundancy
  • Up to 504xE1 DS0 cross connection



  • Cross-connect in VC-12, VC-3 and VC-4
  • Permits cross connection of 64bit/s timeslots with a capacity of 504 E1s



  • Includes 2 slots for E1, E3/T3, Ethernet and SDH interface modules
  • Includes 2 slots for reduced interface modules with E1 and housekeeping



  • Internal clock;
  • 2048kHz external clock input via a connector in the DM820-ICRHK module;
  • SDH and E1 interface regenerated clock.


Power Supply

  • Supports inputs from -48 up to -60VDC or 100 up to 240VAC
  • All modules include a redundant power circuit


Fan Control

  • Rotation monitoring
  • Supports 2 redundant fan modules
  • Speed control based on equipment temperature