DM820 Compact STM16 SDH Multiplexer

DM820 Compact 2U STM1/4/16 SDH MultiplexerThe DM820 is a new generation multi-service access platform shelf of 2U high, compatible with standard 19-inch racks. It adds multiservice functionality to the access applications for transport networks. Has a nonblocking SDH cross-connection matrix with 4G capacity and granularity of VC-4/3/12, cross-connection DS0 matrix (64kbit/s) with 252 E1s capacity, STM-4/1, Fast and Gigabit Ethernet, E1 and E3 interfaces. All these features enable the implementation of voice, video and data services with reduced cost.

DM820 Datasheet

Interface Cards

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.


  • Dimensions: 444.80 x 86.8 x 264.3 mm (W x H x D)
  • Hot-swap on all modules
  • Operation temperature: 0 to 55°C
  • Power consumption: 80W typical, 210W maximum


  • 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


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


DM820 Application
SNCP Rings
DM800 Application
DM800 Series