Muxpad II

Product Information

Muxpad II

Muxpad II

The Muxpad II is a Data Gathering Module (DGM), which is a part of the Digitize System 3505 Prism LX™ Supervised Bidirectional Polling Alarm Monitoring System. For a complete operating system, you also need a System 3505 Prism LX™ with the MULTIPLEX option. The Muxpad II uses Coded Multiplex for communications. The standard communications format for the multiplex system is an isolated RS422/485 driver. Other available line drivers include RS 232, Audio, Fiber Optic, Polling Radio and Ethernet. Connection to the FACP is via an RS-232 port on the Muxpad II.

The Muxpad II is used to monitor addressable fire alarm control panels (FACP). The Muxpad II collects the supervised messages from the FACP serial printer port. As each message is transmitted by the FACP, the Muxpad II gathers the text and interprets it into a more usable format for the SYSTEM 3505 Prism LX™. The new messages are then relayed to the SYSTEM 3505 Prism LX™ via the Muxpad II’s supervised RS-485 serial port.

Upon activation of any new condition, the Muxpad II communicates with the SYSTEM 3505 Prism LX™ to advise new conditions as well as the English text message provided by the FACP. In the event of a data line error, the Muxpad II retains alarm information until communication is reestablished to the SYSTEM 3505 Prism LX™. Upon receiving a command from the SYSTEM 3505 Prism LX™, the Muxpad II can reset the FACP. Other commands (on a limited number of FACP interfaces) include Bell ON/OFF, FACP local ACK, as well as Control Module ON/OFF signals.

The Muxpad II may also be used to monitor end-of-line supervised Dry Contact points of conventional control panels—fire, security, building process, etc. The Muxpad II utilizes eight local zones provided on the board or an optional 32-zone external plug-in board (in a separate or larger enclosure). These zones are EOL resistor supervised and can monitor ALARM, TROUBLE, and SECURE states of the zones

IMPORTANT: In order to maintain the ANSI/UL 864 listing of this product it is mandatory that one zone of the Muxpad II is connected directly to the alarm relay contacts of the FACP being monitored. The RS-232 connection from the Muxpad II to the fire panel is an ancillary connection.


  • Serial interface to addressable FACP and/or dry contacts for conventional fire panel
  • Eight zone supervised EOL inputs with expansion capability for internal 32-zone supervised inputs (in a larger enclosure)
  • Mix & match MUXPAD II with Digitize DGM panels
  • Form C relay on Muxpad II can be turned on/off or momentary with relay control option on the SYSTEM 3505 Prism LX™
  • Monitors alarm, trouble, and secure states
  • Built-in lightning protection on the RS-485 port.
  • Watchdog timer
  • Supervised RS-232 and RS-485 communication links
  • Jumper selectable to monitor FACP, EOL zones or both
  • NFPA-72 Compliant ETL Listed
  • ANSI/UL 864


Communication ProtocolIsolated RS-422/485 standard. Optional protocols include: Supervisory RS485, RS-232, audio modem, polling radio, fiber optic, and Ethernet

Power RequirementsPrimary power Input: 18-27 VDC @200mA max. Connect to either a nonresettable power supply circuit of interconnected control unit or a power supply listed for protective signaling use. DC operating power use: 2.9 Watts (max.); at 12 Volt-200mA; at 24 Volt-120mA

LED IndicatorsMUX LED-illuminates when Muxpad II is transmitting to the System 3505 Prism LX™. FACP LED-illuminates when Muxpad II is receiving a data character from the serial port of the FACP

EnclosureRed steel enclosure with door & CAM (key) lock – 9.25 in. (H) x 13.25 in. (W) x 3.5 in. (D) For Muxpad II with polling radio, see cut sheet 750240

Net Weight7 lbs. (approx. weight for the standard Muxpad II)


Operating Temperature: 0°C to + 50°C

Storage Temperature: 0°C to + 50°C

Operating Humidity: 0-90% (non-condensing)

Storage Humidity: (non-condensing)

Install only in dry, indoor environments.