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Generator and Transfer Switch Monitoring Specifications

The Messenger monitors generators using CANbus (J1939) and Modbus RTU. Transfer switches are typically monitored using Modbus, but also using the digital inputs of the Messenger.

Conditions Monitored
General input conditions
  • GPS coordinates for location
  • General purpose or pulse closure-to-ground input
  • Analog input for fuel level or other sender
Generator and Transfer switch specific parameters (each phase and between phases)
  • AC RMS voltages
  • AC RMS current
  • Reactive Power
  • Power Factor
  • Real Power
  • Apparent Power
  • Control and Auto-start mode
  • AC Frequency
  • Transfer switch position
  • On/Off control of transfer switch and generator
Diesel Engine Conditions Monitored
  • Engine hours
  • RPM
  • Battery voltage (switched and unswitched)
  • Oil pressure, temperature and level
  • Fuel level
  • Coolant level and temperature
  • Throttle position
  • Ambient conditions
  • All diagnostic messages reported via DM1 (J1939) or trouble codes (J1708/1587)
  • Fault conditions reported through TPCM (J1939)
  • User-defined PGN/FMI (J1939) values
  • OEM-specific parameters
  • Computed values reported daily, including:
    • Daily fuel usage and hours
    • Maximum and Minimum RPM
    • Maximum and Minimum Oil pressure, temperature and level
    • Maximum and Minimum Coolant level and temperature
Engine bus support
  • CANbus protocol version 2.0 part A and B/Active
Modbus communications
  • 100 Modbus RTU registers
  • 16- or 32-bit holding, packed digitals, float
  • Data can be raw Modbus or automatically scaled into engineering units
  • Reverse ordering supported
  • Bits can be masked
  • On/Off control supported for many manufacturers via Modbus
Serial ports
  • RS232/RS485
  • External CDMA or Satellite modems
  • Support OEM-specific communication
Battery backed
  • Real-Time Clock
  • Programming
  • Event log
Communication methods to back-end
  • Wi-Fi
  • CDMA
  • Satellite
  • Serial
  • FCC, PTCRB and ATT approvals for GSM/GPRS end-user applications
  • Operating vibration: exceeds SAE J1455 vibration levels
  • Operating shock: exceeds SAE J1455 shock levels
  • Enclosure: exceeds IP65/NEMA 4X
  • RoHS compliant
Power management
  • Extreme low power mode for battery-powered applications
  • Automatic switch out of low power on: movement, engine on, time
Memory management
  • 512k FLASH for application, loadable OTA or via serial connection
  • 512k low-low power SRAM, battery backed
DIP switches
  • Serial port function - Debug, Other
  • Serial port interface - RS232 or RS485
  • Baud rate
Event logger
  • Last 500 significant events
  • Accessible over-the-air
  • Accessible locally via serial port
  • Battery backed
  • Power modes - off, low, full
  • Cellular/Wireless status and signal strength
  • GPS status
  • CAN status
  • Serial port status
  • OEM specific
General purpose inputs
  • Up to 3 digital (closure to ground) inputs
  • Analog input - voltage, ma or resistive
  • Digital output (closure to ground)
SMS capabiltiy
  • Receive commands for changing configuration
  • Receive commands for over-the-air direct communications with internal menuing system
  • On-demand reporting of values
  • OEM specific
Physical Characteristics
  • 3.25" x 3.95"
  • Operating power: 8-32VDC
  • Sleep mode - less than 6 ma @ 12VDC
  • Monitoring mode - 110ma @ 12VDC
  • GPRS transmit mode - 600ma peak @ 12VDC
  • Industrial temperature range -40 to +85C
  • Watertight industrial enclosure