ONICON System-40 BTU Measurement

Description

The System-40 provides highly accurate thermal energy measurement in chilled water, hot water or condenser water systems. It is provided as a complete meter and includes a matched pair of platinum RTD temperature sensors and an integral inline ultrasonic flow sensor. It is available for use in ½” through 2½” piping systems with flow rates ranging from 0.03 to 250 GPM.

Application

Monitoring chilled water, hot water and condenser water in AHU and CRAC units for:

•  Commercial office tenant billing
•  Residential apartment and condominium tenant billing

Monitoring renewable energy resources for:

• Solar thermal applications
• Ground source heat pumps
• Geothermal heating systems

Features

• Reliable No-Moving-Parts Design – 
  • Wetted transducers measure the ultrasonic signal transit time differential, which correlates directly to the flow rate. The direct beam path orientation significantly enhances signal strength and long term reliability.
• Highly Accurate Over a Wide Flow Range –
  • The flow sensor is accurate to within ±1% of reading over the normal (25:1 turndown)
  • operating range and within ±2% of reading over an extended (100:1 turndown) range.
• User-Friendly Backlit Display – 
  • The bright, easy-to-read, backlit display uses “smart button technology” to simplify page navigation and programming. This eliminates the need for special configuration tools.
• Matched Platinum 1000Ω RTD Temperature Sensors
  • Sensors are paired in a matching process that ensures a differential measurement uncertainty of better than ±0.18°F.
• Suitable for Water and Water/Glycol Solutions
  • System-40 is field programmable for both water and water/glycol solutions to ensure accurate flow and energy measurement.
• Detachable Display
  • The display for the system-40 is easily detached from the flow sensor. This allows for remote mount installation up to 5ft from the sensor body.
• Built-in Interval Data Logger
  • Energy and volume totals are date/time stamped and logged within the meter along with other analytical data. This data is available via BACnet®.
• ACCURACY
  • ±1% of reading over 25:1 turndown
  • ±2% of reading over 100: 1 turndown
  • Overall turndown exceeds 500: 1
  • Repeatability: ≤±0.2%
  • Meets EN1434 Class 1 accuracy requirements
• TEMPERATURE SENSORS 
  • Field serviceable MID certified matched pair of 2-wire 1000Ω platinum RTDs
  • Calibrated to a differential measurement uncertainty of ±0.18°F
  • Meets EN1434/C900.1 accuracy requirements for 3K sensors
• CALCULATOR
  • Computation error: ≤ 0.09% at 30°F Δt
  • Meets EN1434 Class 1 requirements with 3K minimum Δt
• PIPE SIZE RANGE
  • ½ – 2½” nominal diameter
• PIPING SYSTEM CONNECTIONS
  • Male NPT threads
  • 2½” meter provided with ANSI Class 150 raised face flanges
• FLUID TEMPERATURE RANGE
  • 32 to 250°F
• MAXIMUM OPERATING PRESSURE
  • 400 psi
• PRESSURE DROP
  • Less than 1 psi at 4 ft/s, decreasing at lower velocities
• MATERIALS
  • Wetted components: Lead-free brass, PEEK
  • Enclosure: Polycarbonate
• ENVIRONMENTAL
  • Meets EN1434/C900.1 Class A requirements
  • Operating Temperature Range: -13 to 131°F
  • Storage Temperature Range: -14 to 158°F
  • Enclosure Rating: IP65
• POWER SUPPLY REQUIREMENTS
  • 20-28V AC/DC, 50/60 Hz, 5 VA maximum
• ISOLATED ANALOG OUTPUT
  • Maybe programmable for energy rate, flow rate, supply temperature, return temperature or Δt
  • Configurable as: 4-20mA, 0-5 V or 0-10 V output
• ISOLATED TOTALIZING SOLID STATE CONTACT CLOSURE PULSE OUTPUTS
  • Maybe programmed for energy, volume, alarm indication, mode indication or MODBUS coil indication
  • Contact ratings: 50 mA, 30 V
  • Contact pulse duration: 50, 100, 500 or 1000 ms
• ISOLATED TOTALIZING PULSE INPUTS
  • For use with sinking open collector or dry contact outputs
  • Input rating: 30 VDC, 10 mA maximum
  • Pulse duration: 50 ms minimum
• NETWORK CONNECTIONS
  • Isolated RS485 serial interface
• COMMUNICATION PROTOCOLS
  • BACnet® MS/TP per ASHRAE Standard 135.1: 2009
  • MODBUS® RTU
• NETWORK CONFIGURATION & ADDRESSING
  • Baud Rates: 4800, 9600, 19200, 38400, 76800, or 115200
  • Device Address Range: 1 – 255 (1 – 247 MODBUS® RTU)
  • Device Instance Range: 1 – 4,194,303 (BACnet® only)
  • Parity: None, Even, Odd (MODBUS® RTU only)