![]() Heavy duty models are available that can measure in excess of 6000 FPM. Hot wires are not recommended for air velocities exceeding 2000 FPM unless they are specifically designed for that purpose. ![]() Care must be used when measuring conditioned and turbulent air. Hot wires are best suited for low velocity measurements at or near standard air conditions. Many are calibrated to standard air which is 68F 0%Rh and 29.92mmhg. Hot wires are calibrated to a specific air density and either require the density to be input to the meter or a correction to be made. The airflow should not be inferred by dampers. Air velocity: 0.2 to 35.0 m/s, wide range and high precision. In an ideal location the duct will have a minimum of 10 diameters before the measuring spot and at least 4 diameters after before making a transition of turn. Complete set with two probes: Hot wire anemometer probe and Humidity/Temp. Measurement Location and SelectionĪll measurements should be made in a straight section of duct if possible. This characteristic is typically prevalent in ducts where turbulent airflow can occur even at very low velocities. This could indicate a higher measured value than a vane probe. When using a hot wire in turbulent air streams the measured results can be impacted by turbulent airflow striking the measurement sensor from multiple directions. The temperature of the hot wire is kept constant via a regulating switch, and the current (amp draw measured internally) is directly proportional to the air velocity. The principal of a hot wire anemometer is based on a heated element from which heat is extracted by the colder impact airflow. Measuring Airflow With a Hot Wire Anemometer
0 Comments
Leave a Reply. |