BACnet Field Control Device

BACnet Advanced Application Controller

DACU842B+ - BACnet Field Control Device - BACnet Advanced Application Controller


DACU842B+ is a standalone BACnet B-AAC class programmable controller with a LCD control panel. It is designed for monitor and control building electromechanical device, large AHU, clean room, fume hood, large-scale end device control. It uses 32-bit microprocessor core, communication speed up to 76,800 bps, transmission distance up to 1,200 meter. DACU842B+ has 8 Universal Inputs(UI), 4 Binary Outputs(BO) and 2 Analog Outputs(AO).

In addition it has an EIMnet port can connect up to 4 EIM series of expansion modules, allowing you to expand in response to needs of various points. DACU842B+ conforms to international BACnet MS/TP communication protocol and fully compatible with any BACnet system. It is absolutely the best product for your building.  


  • Conforms to ASHRAE and ISO16484-1 defined BACnet AAC standard communication protocol, compatible with BACnet system.
  • An MS/TP(Master-Slave/Token-Passing) communication interface, with Peer to Peer function can read and write other DDC’s object, may issue a read (DS-RP-A/DS-RPM-A) and write (DS-WP-A) BACnet object properties function.
  • An EIMnet communication interface can connect up to 4 EIM I/O expansion modules.
  • Universal Input (UI) has 12-bit resolution, accept dry contact, pulse, 3K or 10KΩ NTC thermistor, 0~5VDC, 0~10VDC, 0~20mA or 4~20mA input signal.
  • Binary Output (BO) has 5,000Vrms optical coupling isolator, 8A/250VAC/SPST relay (Relay), Status Indicator design. Each point has a manual on / off / auto three sections selector switch.
  • Analog Output (AO) has 12-bit resolution, can be DIP switch and software selected as 0~10VDC or 2~10VDC output signal, each point has a manual override/auto output control switch.
  • User’s control program can be downloaded, edited and saved in flash memory of the controller.    
  • Carry out calculations such as proportional, integral, differential, floating, logic, arithmetic and etc.
  • 150 Binary Value(BV) and 150 Analog Value(AV) points, the analog value adopts high precision floating-point calculation.
  • Priority control array by 16 for all BO, AO and BV.
  • Provide power failure backup function for all AI/BO/AO/BV/AV values keep in FRAM for at least 10 years.
  • Real-time clock, 2 Calendars, 12 Schedules, 4 Notification Class, 20 Event Enrollments standard BACnet object. Schedules and event enrollments support external object access function.

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