ansi.pdf
- 1. GEDigitalEnergy.com 1 ANSI Standard Device Numbers & Common Acronyms Suffixes Description _1 Positive-Sequence _2 Negative-Sequence A Alarm, Auxiliary Power AC Alternating Current AN Anode B Bus, Battery, or Blower BF Breaker Failure BK Brake BL Block (Valve) BP Bypass BT Bus Tie BU Backup C Capacitor, Condenser, Compensator, Carrier Current, Case, or Compressor CA Cathode CH Check (Valve) D Discharge (Valve) DC Direct Current DCB Directional Comparison Blocking DCUB Directional Comparison Unblocking DD Disturbance Detector DUTT Direct Underreaching Transfer Trip E Exciter F Feeder, Field, Filament, Filter, or Fan G Ground or Generator GC Ground Check H Heater or Housing L Line or Logic M Motor or Metering MOC Mechanism Operated Contact N Neutral or Network O Over P Phase or Pump PC Phase Comparison POTT Pott: Permissive Overreaching Transfer Trip PUTT Putt: Permissive Underreaching Transfer Trip R Reactor, Rectifier, or Room S Synchronizing, Secondary, Strainer, Sump, or Suction (Valve) SOTF Switch On To Fault T Transformer or Thyratron TD Time Delay TDC Time-Delay Closing Contact TDDO Time Delayed Relay Coil Drop-Out Suffixes Description TDO Time-Delay Opening Contact TDPU Time Delayed Relay Coil Pickup THD Total Harmonic Distortion TH Transformer (High-Voltage Side) TL Transformer (Low-Voltage Side) TM Telemeter TT Transformer (Tertiary-Voltage Side) U Under or Unit X Auxiliary Z Impedance Acronyms Description AFD Arc Flash Detector CLK Clock or Timing Source CLP Cold Load Pickup DDR Dynamic Disturbance Recorder DFR Digital Fault Recorder ENV Environmental Data HIZ High Impedance Fault Detector HMI Human Machine Interface HST Historian MET Substation Metering PDC Phasor Data Concentrator PMU Phasor Measurement Unit PQM Power Quality Monitor RIO Remote Input/Output Device RTD Resistance Temperature Detector RTU Remote Terminal Unit / Data Concentrator SER Sequence of Events Recorder TCM Trip Circuit Monitor VTFF Vt Fuse Fail
- 2. GEDigitalEnergy.com 2 Device No. Description 1 Master Element 2 Time Delay Starting or Closing Relay 3 Checking or Interlocking Realy 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 Multifunction Device 12 Overspeed Device/Protection 13 Synchronous-Speed Device 14 Underspeed Device 15 Speed or Frequency Matching Device 16 Communication Networking Device 17 Shunting or Discharge Switch 18 Accelerating or Decelerating Device 19 Motor Starter / Starting-to-Running Transition Contactor 20 Electrically-Operated Valve 21 Distance Relay 21G Ground Distance 21P Phase Distance 22 Equalizer Circuit Breaker 23 Temperature Control Device 24 Volts-per-Hertz Relay / Overfluxing 25 Synchronizing or Synchronism-Check Device 26 Apparatus Thermal Device 27 Undervoltage Relay 27P Phase Undervoltage 27TN Third Harmonic Neutral Undervoltage 27X Auxiliary Undervoltage 27 AUX Undervoltage Auxiliary Input 27/27X Bus/Line Undervoltage 28 Flame Detector 29 Isolating Contactor 30 Annunciator Relay 31 Separate Excitation Device 32 Directional Power Relay 32L Low Forward Power 32N Wattmetric Zero-Sequence Directional 32P Directional Power 32R Reverse Power Device No. Description 33 Position Switch 34 Master Sequence Device 35 Brush-Operating or Slip-ring Short Circuiting Device 36 Polarity or Polarizing Voltage Device 37 Undercurrent or Underpower Relay 37P Underpower 38 Bearing Protective Device / Bearing Rtd 39 Mechanical Condition Monitor 40 Field Relay / Loss of Excitation 41 Field Circuit Breaker 42 Running Circuit Breaker 43 Manual Transfer or Selector Device 44 Unit Sequence Starting Relay 45 Atmospheric Condition Monitor 46 Reverse-Phase or Phase Balance Current Relay or Stator Current Unbalance 47 Phase-Sequence or Phase Balance Voltage Relay 48 Incomplete Sequence Relay / Blocked Rotor 49 Machine or Transformer Thermal Relay / Thermal Overload 49RTD RTD Biased Thermal Overload 50 Instantaneous Overcurrent Relay 50BF Breaker Failure 50DD Current Disturbance Detector 50G Ground Instantaneous Overcurrent 50N Neutral Instantaneous Overcurrent 50P Phase Instantaneous Overcurrent 50_2 Negative Sequence Instantaneous Overcurrent 50/27 Accidental Energization 50/74 Ct Trouble 50/87 Instantaneous Differential 50EF End Fault Protection 50IG Isolated Ground Instantaneous Overcurrent 50LR Acceleration Time 50NBF Neutral Instantaneous Breaker Failure 50SG Sensitive Ground Instantaneous Overcurrent 50SP Split Phase Instantaneous Current 51 Ac Time Overcurrent Relay 51 Overload 51G Ground Time Overcurrent 51N Neutral Time Overcurrent 51P Phase Time Overcurrent 51V Voltage Restrained Time Overcurrent 51R Locked / Stalled Rotor ANSI Standard Device Numbers & Common Acronyms
- 3. GEDigitalEnergy.com 3 Device No. Description 51_2 Negative Sequence Time Overcurrent 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 59B Bank Phase Overvoltage 59P Phase Overvoltage 59N Neutral Overvoltage 59NU Neutral Voltage Unbalance 59P Phase Overvoltage 59X Auxiliary Overvoltage 59_2 Negative Sequence Overvoltage 60 Voltage or Current Balance Relay 60N Neutral Current Unbalance 60P Phase Current Unbalance 61 Density Switch or Sensor 62 Time-Delay Stopping or Opening Relay 63 Pressure Switch Detector 64 Ground Protective Relay 64F Field Ground Protection 64S Sub-harmonic Stator Ground Protection 64TN 100% Stator Ground 65 Governor 66 Notching or Jogging Device/Maximum Starting Rate/Starts Per Hour/Time Between Starts 67 Ac Directional Overcurrent Relay 67G Ground Directional Overcurrent 67N Neutral Directional Overcurrent 67P Phase Directional Overcurrent 67SG Sensitive Ground Directional Overcurrent 67_2 Negative Sequence Directional Overcurrent 68 Blocking Relay / Power Swing Blocking 69 Permissive Control Device 70 Rheostat 71 Liquid Switch 72 Dc Circuit Breaker 73 Load-Resistor Contactor 74 Alarm Relay 75 Position Changing Mechanism Device No. Description 76 Dc Overcurrent Relay 77 Telemetering Device 78 Phase Angle Measuring or Out-of-Step Protective Relay 78V Loss of Mains 79 Ac Reclosing Relay / Auto Reclose 80 Liquid or Gas Flow Relay 81 Frequency Relay 81O Over Frequency 81R Rate-of-Change Frequency 81U Under Frequency 82 Dc Reclosing Relay 83 Automatic Selective Control or Transfer Relay 84 Operating Mechanism 85 Carrier or Pilot-Wire Receiver Relay 86 Locking-Out Relay 87 Differential Protective Relay 87B Bus Differential 87G Generator Differential 87GT Generator/Transformer Differential 87LG Ground Line Current Differential 87S Stator Differential 87S Percent Differential 87L Segregated Line Current Differential 87M Motor Differential 87O Overall Differential 87PC Phase Comparison 87RGF Restricted Ground Fault 87T Transformer Differential 87V Voltage Differential 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 50/74 Ct Supervision 27/50 Accidental Generator Energization 27TN/59N 100% Stator Earth Fault