Pilot device Flashcards
Name some facts about sensors vs Switches
- Sensor is a broad term given to any device that aquires inforamtion from a process
- A switch is a type of sensor that operates contacts, but a sensor is not necessarily a swtich
What type of things will fall under sensor category
Switches
tranducers
rotary
encoders
resolvers
What is this device?
how can it be used
draw the schematic symbol
A micro switch
Can be used by themselfs to sense position, or used in other devices to provide form C contacts
How does a pressure switch operate?
draw its symbol
Pressure is sensed to be above or below a certain level
adjustable
adustable differential ( difference between trip point and reset point)
what is this circuit
flow switch
What are the differnt contact types for limit switch and draw its symbol
NO,NC,NOHC,NCHO
Why are proximity switches used
draw its symbol
They allow a limit switch function without making contact with moving machinery
How does inductive proximity switch work
operates set of contacts or transistor outputs when ferric metal enters the set area
What would capacitive poximity switch be used
To operate a set of contacts when a non metallic object enters the set area.
often use transistor outputs
How do photo switches work what are possible outputs
Output can be transistor or receiver
they are opertaed by meab being broken or by beam not being broken
What is the Hall effect
Presence of magnetic field affects semiconductor characteristics.
field is sensed by change in voltage across the semiconductior with a constant current through it.
what can ultrasonic detector be used for?
To sence postition, solid and liquid levels and in counting applications
Name each of these solenoid valve symbols
What is solenoid valve used for
also draw symbol
Allows turning flow of fluids (air, water,oil, hydralic fluid etc) on or off
by energizing or de energiing its coil
