Relays IEEE Number

List of device numbers and acronyms

• 1 – Master Element
• 2 – Time Delay Starting or Closing Relay
• 3 – Checking or Interlocking Relay
• 4 – Master Contactor
• 5 – Stopping Device
• 6 – Starting Circuit Breaker
• 7 – Rate of Change Relay
• 8 – Control Power Disconnecting Device
• 9 – Reversing Device
• 10 – Unit Sequence Switch
• 11 – Multi-function Device
• 12 – Overspeed Device
• 13 – Synchronous-speed Device
• 14 – Underspeed Device
• 15 – Speed – or Frequency, Matching Device
• 16 – Data Communications Device
• 17 – Shunting or Discharge Switch
• 18 – Accelerating or Decelerating Device
• 19 – Starting to Running Transition Contactor
• 20 – Electrically Operated Valve
• 21 – Distance Relay
• 22 – Equalizer Circuit Breaker
• 23 – Temperature Control Device
• 24 – Volts Per Hertz Relay
• 25 – Synchronizing or Synchronism-Check Device
• 26 – Apparatus Thermal Device
• 27 – Undervoltage Relay
• 28 – Flame detector
• 29 – Isolating Contactor or Switch
• 30 – Annunciator Relay
• 31 – Separate Excitation Device
• 32 – Directional Power Relay
• 33 – Position Switch
• 34 – Master Sequence Device
• 35 – Brush-Operating or Slip-Ring Short-Circuiting Device
• 36 – Polarity or Polarizing Voltage Devices
• 37 – Undercurrent or Underpower Relay
• 38 – Bearing Protective Device
• 39 – Mechanical Condition Monitor
• 40 – Field (over/under excitation) Relay
• 41 – Field Circuit Breaker
• 42 – Running Circuit Breaker
• 43 – Manual Transfer or Selector Device
• 44 – Unit Sequence Starting Relay
• 45 – Abnormal Atmospheric Condition Monitor
• 46 – Reverse-phase or Phase-Balance Current Relay
• 47 – Phase-Sequence or Phase-Balance Voltage Relay
• 48 – Incomplete Sequence Relay
• 49 – Machine or Transformer, Thermal Relay
• 50 – Instantaneous Overcurrent Relay
• 51 – AC Inverse Time Overcurrent Relay
• 52 – AC Circuit Breaker
• 53 – Exciter or DC Generator Relay
• 54 – Turning Gear Engaging Device
• 55 – Power Factor Relay
• 56 – Field Application Relay
• 57 – Short-Circuiting or Grounding Device
• 58 – Rectification Failure Relay
• 59 – Overvoltage Relay
• 60 – Voltage or Current Balance Relay
• 61 – Density Switch or Sensor
• 62 – Time-Delay Stopping or Opening Relay
• 63 – Pressure Switch
• 64 – Ground Detector Relay
• 65 – Governor
• 66 – Notching or Jogging Device
• 67 – AC Directional Overcurrent Relay
• 68 – Blocking or "Out-of-Step" Relay
• 69 – Permissive Control Device
• 70 – Rheostat
• 71 – Liquid Level Switch
• 72 – DC Circuit Breaker
• 73 – Load-Resistor Contactor
• 74 – Alarm Relay
• 75 – Position Changing Mechanism
• 76 – DC Overcurrent Relay
• 77 – Telemetering Device
• 78 – Phase-Angle Measuring Relay
• 79 – AC Reclosing Relay
• 80 – Flow Switch
• 81 – Frequency Relay
• 82 – DC Reclosing Relay
• 83 – Automatic Selective Control or Transfer Relay
• 84 – Operating Mechanism
• 85 – Communications,Carrier or Pilot-Wire Relay
• 86 – Lockout Relay
• 87 – Differential Protective Relay
• 88 – Auxiliary Motor or Motor Generator
• 89 – Line Switch
• 90 – Regulating Device
• 91 – Voltage Directional Relay
• 92 – Voltage and Power Directional Relay
• 93 – Field Changing Contactor
• 94 – Tripping or Trip-Free Relay
• 95 – For specific applications where other numbers are not suitable
• 96 – For specific applications where other numbers are not suitable
• 97 – For specific applications where other numbers are not suitable
• 98 – For specific applications where other numbers are not suitable
• 99 – For specific applications where other numbers are not suitable
• AFD – Arc Flash Detector
• CLK – Clock or Timing Source
• DDR – Dynamic Disturbance Recorder
• DFR – Digital Fault Recorder
• ENV – Environmental Data
• HIZ – High Impedance Fault Detector
• HMI – Human Machine Interface
• HST – Historian
• LGC – Scheme Logic
• MET – Substation Metering
• PDC – Phasor Data Concentrator
• PMU – Phasor Measurement Unit
• PQM – Power Quality Monitor
• RIO – Remote Input/Output Device
• RTU – Remote Terminal Unit/Data Concentrator
• SER – Sequence of Events Recorder
• TCM – Trip Circuit Monitor
• SOTF – Switch On To Fault