Chapter - Logical Sensors

1
Chapter - Logical Sensors
Sensor output types
Sinking/Sourcing - Switches current on or
off. Plain Switches - Switches voltage on or
off. Solid State Relays - These switch AC
outputs. TTL (Transistor Transistor Logic) - Uses
0V and 5V.
2
Switched outputs (e.g. Relays)
3
Sourcing (supplies voltage/current)
4
Sinking (to the common)
5
Wiring
6
A PLC Input Card For a Sinking (NPN) Sensor
7
PLC Input card for Sourcing (PNP) sensors
8
Symbols and Wiring Conventions
9
Photo-optical sensors
10
Photo-optic - Opposed mode
11
Photo-optic - retroreflective
12
Photo-optic - Diffuse
13
Photo-optic alignment and beam size
14
Photo-optics - focussed
15
Optical Properties
16
Capacitive Sensors
17
Relative Capacitive Values
18
Inductive sensors
19
Other sensor types
Reed switches Hall effect switches Fluid
flow Etc.
20
Sensor tradeoffs
Material Distance Accuracy ..