Design & Supply of the Thermal Dispersion Airflow Measurement Stations

Thermal flow meters have two sensors immersed into the flow stream: a “Temperature Sensor(s)” which measures the actual air temp inside the duct as a reference-regardless of flow velocity and heated sensor called a “Velocity Sensor(s).”
Thermal dispersion mass flow meters use heat to measure flow. The Velocity Sensor is heated continuously via electrical wattage, so that a predefined temp differential is always maintained. As the air flow begins, heat is drawn from heated Velocity Sensor via air molecules flowing past. Heat is dispersed as it is carried off by the flow. Knowing the duct size, the cooling effect is then converted to airflow by a precise electronic microprocessor controller.

A total of 289 high accuracy Air Flow Stations of different sizes & sensors arrangements were supplied to the project. Each flow station has the below features:

• High Accuracy Measurement, 2% of Full Scale
• Transmitter with display
• Temperature and velocity outputs
• Outputs are field selectable: 0-5/0-10 VDC or 4-20 mA; BACnet MS/TP; Modbus RTU or JCI N2
• Programmable alarm, can be engaged for user defined Hi or Low limit
• Integration with the Building Management System

Supply of the Instantaneous Water Heaters

Instantaneous water heaters are used to provide hot water to the water taps. With a Compact size, no venting required, can be installed closer to where you use hot water to save energy and water. A Total of 623 tankless water heaters are supplied & installed in the project.

System Features:

• High Accuracy Measurement, 2% of Full Scale
• Transmitter with display
• Temperature and velocity outputs
• Outputs are field selectable: 0-5/0-10 VDC or 4-20 mA; BACnet MS/TP; Modbus RTU or JCI N2
• Programmable alarm, can be engaged for user defined Hi or Low limit
• Integration with the Building Management System

Description of Operation
Based on the demand initiated by opening the water tap & sensed by a flow switch; the microprocessor based controller will start to modulate the heater to achieve the required outlet temperature setpoint “Factory adjusted”. Three temperature sensors are factory installed at the inlet of the unit and end of each heating chamber, allowing the controller to see the temperature at the beginning and end of each heating section. The controller will compare the water temperature reading at the inlet & modulate the heater to achieve the setpoint.