Read below to view Turck's technical reference regarding NAMUR sensor outputs.
NAMUR (Y0 and Y1) Output
NAMUR sensors are 2-wire sensing devices used with switching ampliers. Because of the small amount of energy needed to operate NAMUR sensors, they can be used in intrinsically safe applications.
The operation of this sensor is similar to that of a variable resistor with a change in impedance as a target approaches the sensor. When no metal is being sensed, the inductive sensor is in a low impedance state and draws a current of more than 2.2 mA. When a metal target enters the high-frequency field radiated from the sensor head, the impedance increases as the target approaches. When fully damped, the sensor draws less than 1.0 mA. Note: For capacitive and inductive magnet operated sensors, the current change characteristics are opposite.
The current differential from the undamped to the damped (metal present) state is used to trigger an amplifier at a defined switching point. These sensors contain a relatively small number of components, which allows the construction of small devices and also assures a high degree of reliability.
In the undamped and damped state, the devices have fairly low impedance and are therefore, unaffected by most transients. NAMUR sensor circuits operate on direct current. Therefore, cable runs of several sensors may be run parallel to one another without mutual interference.
Typical Output Curves