Electronics (Leaving Cert Engineering): Flashcards
📚Flashcards
Practise the cards
15 cards from this deck
ShowHide
Practise the cards
15 cards from this deck
Role of sensors & switches in engineering systems
Role of sensors & switches in engineering systems
Interface between physical world and electronic control systems
Mechanism used by mechanical switches
Mechanism used by mechanical switches
Cam and plunger mechanism
Normally Closed (NC) switch behaviour when activated
Normally Closed (NC) switch behaviour when activated
Moves from closed position to open
Normally Open (NO) switch behaviour when activated
Normally Open (NO) switch behaviour when activated
Moves from open position to closed
Mechanical switch advantage for extreme conditions
Mechanical switch advantage for extreme conditions
High temperature tolerance
Safety feature of NC mechanical switches in power failure
Safety feature of NC mechanical switches in power failure
Fail to safe operation
What photoelectric sensors detect
What photoelectric sensors detect
Changes in light intensity
Most common photoelectric sensor mode in linear actuators
Most common photoelectric sensor mode in linear actuators
Through-beam mode
How proximity sensors detect targets
How proximity sensors detect targets
Emit electromagnetic field to detect metal targets
Typical sensing distance limit for proximity sensors
Typical sensing distance limit for proximity sensors
50mm or less
How reed switches are activated
How reed switches are activated
Magnetic activation (magnetic field)
Why reed switches suit hazardous environments
Why reed switches suit hazardous environments
Intrinsically safe due to hermetically sealed glass envelope
Type of device Hall sensors are
Type of device Hall sensors are
Solid-state devices
Hall sensor lifetime advantage
Hall sensor lifetime advantage
Virtually infinite lifetime (no moving parts)
Priority order for sensor selection
Priority order for sensor selection
- Reliability 2. Operating environment 3. Performance vs cost