Phase 6: Relays & Relay Logic
This phase contains 10 sections and 85 checklist topics. Use the interactive phase page to track your own learning progress.
6.1 Relay basics
- What is relay?
- Why relay?
- Electromagnetic principle
- Coil
- Core
- Armature
- Spring
- Contacts
- And 3 more checklist topics
6.2 Relay operation
- Coil OFF
- Coil energized
- Magnetic field
- Armature movement
- Contact change
- Coil de-energized
- Spring return
6.3 Terminals
- A1/A2
- 11/12/14
- 21/22/24
- Coil terminals
- COM
- NO
- NC
6.4 Relay ratings
- Coil voltage
- Coil current
- Contact voltage
- Contact current
- AC rating
- DC rating
- Resistive-load rating
- Inductive-load rating
- And 2 more checklist topics
TOP PRIORITY
- General-purpose relay
- Plug-in relay
- Interposing relay
- Interface relay
- Timer relay
- Safety relay
- Overload relay
- Phase monitoring relay
SECOND PRIORITY
- Solid-state relay
- Latching relay
- Voltage monitoring relay
- Current monitoring relay
- Phase-sequence relay
- Earth-fault relay
- Frequency relay
- Level relay
- And 2 more checklist topics
BASIC AWARENESS
- Reed relay / glass relay
- Automotive relay
6.6 Relay logic
- AND logic
- OR logic
- NOT logic
- Holding
- Latching
- Seal-in
- Interlocking
- Mutual interlocking
- And 3 more checklist topics
6.7 Remote control wiring
- What is remote wiring?
- Local START/STOP
- Remote START/STOP
- Multiple START stations
- Multiple STOP stations
- START buttons in parallel
- STOP buttons in series
- Local/Remote selector
- And 3 more checklist topics
6.8 Safety relay awareness
- Safety relay purpose
- Dual-channel input
- Emergency stop
- Guard switch
- Reset
- EDM/feedback monitoring
- Safety contactor feedback
- Fail-safe wiring