Page 125 - Sensors and Control Systems in Manufacturing

86
T w o
Cha p te r

Output Configuration Target State Oscillator State Output
NO Absent Undamped Nonconducting (OFF)
Present Damped Conducting (ON)
NC Absent Undamped Conducting (ON)
Present Damped Nonconducting (OFF)

TABLE 2.8 Output Logic

FIGURE 2.75 (+) (–)
Single output.

Load

FIGURE 2.76 L1 L2
Programmable
output.
1 2
Load
3 4

A complementary output sensor has two outputs, one NO and
one NC. Both outputs change state simultaneously when the target
enters or leaves the sensing field. These sensors are exclusively three-
wire AC or DC (Fig. 2.77).
The choice of control circuit and output logic plays an important
part in determining the reliability of data collection. The choice of con-
trol circuit and output logic depends on the following parameters:

FIGURE 2.77
Complementary
output.