Celectric Sdn Bhd
Contrec 212 BTU Meter Product Highlights
Contrec 212 BTU Meter is designed to measure the energy consumed in both heating and cooling (air conditioning) systems.
The instrument is normally supplied complete with temperature probes and power supply, and will interface to a wide variety of flowmeters, including positive displacement and inferential water meters, magnetic flowmeters with pulse outputs, turbine flowmeters & paddlewheel flowmeters.
Contrec 212 BTU Meter measures the temperature in the feed and return flow lines and uses this information to calculate the density and enthalpy of water.
By also measuring the volume of water flowing in the system, the Model 212 will then determine the energy used. Calculate power as:
P = V x ᵨ x (hTV – hTR)
where P = Power (W)
V = Volumetric Flow rate (m3/sec)
ᵨ = Density (kg/m3)
hTV = Specific Enthalpy (J/kg) at Feed Temperature
hTR = Specific Enthalpy (J/kg) at Return Temperature
For typical water heating or cooling systems Contrec 212 design for pressures do not exceed 16 bars.
The temperature in both the feed and return lines is measured via two PT100 resistance temperature devices (RTDs).
Four wire RTDs should be a matched pair, Class A to IEC 751 standard to achieve maximum accuracy.
Contrec 212 complies with OIML R75 and EN1434 standards also includes Meter-bus and RS485 (Modbus RTU) communication links.
BTU Meter includes separate peak and off-peak registers as well as the ability to compute charge and discharge energy in systems where heat may be stored in underground tanks.
Contrec 212 provides pulse output with programmable pulse width from 10 to 500ms.
Contrec 212 BTU Meter has a highly accurate built-in real time clock (2ppm typ) also keep track of logging, peak-on/peak-off points, etc.
After power failure, the real-time clock is able to keep running for two days hence with ±1 minute accuracy, typically.