Thermal Flowmeters use a constant temperature differential (ΔT) technology to measure mass flow rate of air and gases. The thermal mass flow sensor consists of two Resistance Temperature Detectors (RTD’s).
FLOW TRANSMITTERS
> Thermal Mass >
FT1
FT1
BASIC DESCRIPTION
*Power SUpply:DC 12~28V
*Output: DC 4 to 20mA
Pulse, RS485 Modbus, HART
*Display: LCD Indicating
*주위온도:-40 to158°F (-40 to 70°C)
*Enclosure:Ex-Proof, NEMA 4X
*정확도
- 공기:±1% RD; ±0.5% FS
- 다른 가스들: ±1.5% RD; ±0.5% FS
*최대범위:15 to 15,000 SFPM (0.07 to 71 NMPS)
*최소범위:15 to 1,000 SFPM (0.07 to 4.7 NMPS)
*온도 정확도:±1ºF (±0.6°C)
*반응시간:0.8초
*반복성:±0.2% of FS
*최대압력:300 psig (20.7 barg)
*공정온도:-40 to 250°F (-40 to 121°C)
PRINCIPLE
*Reference RTD measures temperature of the gas
*Power to the heated element is regulated by the electronics
*A constant ΔT is maintained
*As mass flow increases, the gas molecules remove heat from the heated element
*Sensing the ∆T reduction, the electronics adds power to maintain a constant ∆T.
*The amount of power applied to the heated element is proportional to the mass flow rate
*The microprocessor linearizes these signals
APPLICATION
*Waste Water Treatment Plants (WWTP)
*Aeration Air
*Bio Gas
*HVAC/Building Automation
*Natural Gas and Air Applications
*Boiler, Furnace, Oven manufactures etc.