The Kurz Series 255 Averaging Flow Transmitter from HMA Instrumentation is a versatile system transmitter designed for measuring flow rates in very large ducts that have non-uniform or unstable velocity profiles and/or wide temperature ranges. The Kurz Series 255 Averaging Flow Transmitter from HMA Instrumentation is a state-of-the-art microprocessor-based system that powers and reads up to 16 independent sensing points, providing a grand average of the flow and temperature.

The Kurz Series 255 Averaging Flow Transmitter from HMA Instrumentation continuously reads and analyses flow and temperature data from the individual channels, and automatically removes channels from the average that are under alarm or have been removed for service or repair. The Series 255 is designed for high reliability and high availability, with multiple and independent power and communication ports, so that wiring issues will not bring down the entire multi-sensor network.

Features include:

• Up to 16 input channels providing point velocity, temperature and sensor fault code
• Flow and temperature measurement data quality indication for event logging
• Maintains a 30-day log of daily flow totals
• Velocity-dependent correction factors for flow-rate calculations
• Optically-isolated loop powered 4-20 mA output
• Two digital inputs
• DI1: External trigger to toggle Maintenance Mode
• DI2: External trigger to initiate Zero-Span Cycle
• Six power/data ports for input channel network segmentation
• Reverse polarity, ESD, Surge, EFT and EMI protection
• Each port current limited to 3 A
• One 4-20 mA non-isolated analogue input
• Battery-backed real-time clock
• User-defined TAG ID and flow area
• Three EEPROM data areas for system configuration restore
• Automatic sensor out-of-tolerance indication, alarm and re-averaging for multi-point flow elements
• Isolated USB to RS-485 port for auxiliary MODBUS connection to individual channels
• Galvanic isolation up to 1 000 V DC
• User‐configurable Imperial or Metric units for mass flow rate, mass velocity and process temperature
• Easy‐to‐use interface
• Backlit display with four lines of 20‐characters each, and a 20-button keypad
• User-configurable flow display (scrolling or static)