Basic Sensing Elements


#1

A sensing element is the physical part of the transducer that is in direct contact with the quantity to be measured, that responds to a stimuli by producing a distinct measurable output.
The Mechanical element that is the most integral part of converting sensed form of energy to another can be roughly divided into five depending on the underlying physical characteristics that brings about the response to the stimuli.

A.

Type - Contacting Spindle, pin or finger
Operation - Displacement to displacement

B. Elastic Member

Type - Proving ring
Operation - Force to displacement

Type - Bellows
Operation - Pressure to displacement

Type - Bourdon Tube
Operation - Pressure to displacement

Type - Diaphragm
Operation - Pressure to displacement

Type - Spring
Operation - Force to displacement

C. Mass

Type - Seismic mass
Operation - Force to displacement

Type - Pendulum scale
Operation - Force to displacement

Type - Manometer
Operation - Pressure to displacement

D. Thermal

Type - Thermocouple
Operation - Temperature to electrical current

Type - Bimaterial
Operation - Temperature to displacement

Type - Temp-stik
Operation - Temperature to phase

E. Hydro- pneumatic

  1. Static

Type - Float
Operation - Fluid level to displacement

Type - Hydrometer
Operation - Specific gravity to displacement

  1. Dynamic

Type - Orifice
Operation - Velocity to pressure

Type - Venturi
Operation - Velocity to pressure

Type - Pilot tube
Operation - Velocity to pressure

Type - Vanes
Operation - Velocity to force

Type - Turbines
Operation - Linear to angular velocity