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RP-1 Abbreviations
Most of the abbreviations shown here are taken from the publication Z32.l3-I946 by the American Standards Association. All are the consensus of opinion of the Engineering Committee of NMRA. Compiled by EIectrical Circuits Committee Copyright 1950
Abbreviations - A thru Do
| Abbreviate | ABbr / | Button | BUT |
| Air Circuit Breaker | ACB | Buzzer | BUZ |
| Alarm | ALM | ||
| Alternating Current | AC | Cable | CA |
| Amber | AMB | Call On | CO |
| American Wire Gage | AWG | Candle Power | CP |
| Ammeter | AM | Capacitor | CAP |
| Ampere | AMP | Capacity | CAP |
| Ampere Hour | AMP HR | Carload | CL |
| Ampere Turn | AT | Cast Iron | CI |
| Amplifier | AMPL | Cement | CEM |
| Annunciator | ANN | Center | CTR |
| Antenna | ANT | Center Line | c and / combined |
| Apartment | APT | Centimeter | CM |
| Apparatus | APP | Centralized Traffic Control | CTC |
| Approach Lighting | APL | Circuit | CKT |
| Approved | APPD | Circuit Breaker | CB |
| Approximate | APPROX | Clear | CLR |
| Area | A | Clockwise | CW |
| Area Drain | AD | Common | COM |
| Armature | ARM | Common Battery | CB |
| Asbestos | ASB | Commutator | COMM |
| Assemble | ASSEM | Condenser | COND |
| Assembly | ASSY | Conductor | COND |
| Assistant | ASST | Conductor Multiple | 3/C |
| Association | ASSN | Conduit | CND |
| Attach | ATT | Connect (ion) | CONN |
| Audible | AUD | Contact | CONT |
| Audio Frequency | AF | Container | CONTR |
| Authorised | AUTH | Continue | CONT |
| Automatic | AUTO | Control (ler) | CONT |
| Automatic Train Control | ATC | Coupling | CPLG |
| Auxillary | AUX | Cross (ing) | X |
| Avenue | AVE | Cross Arm | X-ARM |
| Cross Connection | X-CONN | ||
| Back Connected | BC | Crossover | X-O |
| Back Feed | BF | Crystal | XTAL |
| Balance | BAL | Current | CUR |
| Ball Bearing | BB | Cut Out | CO |
| Barrel | BBL | Cycle | CY |
| Basement | BSMT | Cycles/Second | CPS |
| Battery | BAT | ||
| Bill of Material | B/M | Decalcomania | DECAL |
| Black | BLK | Decimal | DEC |
| Block | BLK | Department | DEPT |
| Blue | BLU | Diagram | DIAG |
| Board | BD | Diameter | DIA |
| Breaker | BKR | Direct Current | DC |
| Brown | br /N | Distance | DIST |
| Brown & Sharpe | B&S | Down | DN |
| Brush | br / | Double Pole Switch | DPSW |
Abbreviations - Do thru Ne
| Double Pole Double Throw | DPDT | Inches/Second | IPS |
| Double Pale Single Throw | DPST | Inductance | I |
| Inside Diameter | ID | ||
| Each | EA | Instrument | INST |
| East | E | Insulate | INS |
| Electric | ELEC | Interlock | INTLK |
| Emergency | EMER | Inverse | INV |
| Engine | ENG | ||
| Engine House | EH | Jack | JK |
| Engineer | ENGR | Joint | JT |
| Entrance | ENT | Journal | JNL |
| Junction | JCT | ||
| Feed Water | FW | Junction Box | JB |
| Feet/Minute | FPM | ||
| Feet/Second | FPS | Key | K |
| Field | FLD | Kilo | K |
| Figure | FIG | Kilocycle | KC |
| Filament | FIL | Kilogram | KG |
| Filter | FLT | Kilometer | KM |
| Fluorescent | FLUOR | Kilovolt | KV |
| Foot | ' or FT | Kilowatt | KW |
| Foot Pounds | '# or FT LD | Thousand | K |
| Frame | FR | ||
| Freight | FRT | Left | L |
| Frequency | FREQ | Length | LG |
| Fresh Water | FW | Light | LT |
| Front | FR | Limit Switch | LS |
| Fuel | F | Line | LN |
| Fuel Oil | FO | Lock | LK |
| Long | LG | ||
| Gage or Gauge | GA | Low Voltage | LV |
| Gallon | GAL | Inductance | L |
| Gallons/Hour | GPH | Pound | LB |
| General | GENL | ||
| Generator | GEN | Magnet | MAG |
| Glass | GL | Manufacture | MFR |
| Grade | GR | Maximum | MAX |
| Grade Line | GL | Meter (instrument or measurement) | M |
| Gravel | GVL | Miles | MI |
| Gravity | G | Miles/Hour | MPH |
| Green | GRN | Milliampere | MA |
| Ground | GND | Milligram | MG |
| Millimeter | MM | ||
| Hand Control | HC | Million (See Note) | M |
| Hand Generator | HG | Minimum | MIN |
| Height | HGT | Minute | ' or MIN |
| High Frequency | HF | Model | MOD |
| High Voltage | HV | Motor | MOT |
| Highway | HWY | Motor Generator | MG |
| Home | H | Multiple | MULT |
| Horsepower | HP | Multiple Contact | MC |
| Identity | IDENT | Noon (Mid-day) | M |
| Ignition | IGN | ||
| Inch | " or IN | Negative | - or NEG |
Abbreviations - Ne thru Sh
| Network | NET | Power Factor | PF |
| Neutral | NEUT | Power House | PH |
| Noon | M | Primary | PRI |
| Normal | NOR | Proposed | PROP |
| North | N | Protection | PROT |
| Not to Scale | NTS | Public Address | PA |
| Number | # or NO. | Push Button | PB |
| Obsolete | OBS | Quality | QUAL |
| Ohm | OHM | Quantity | QTY |
| Operate | OPR | Quart | QT |
| Orange | ORN | ||
| Original | ORIG | Radio Frequency | RF |
| Oscillate | OSC | Radius | R |
| Ounce | OZ | Railroad | RR |
| Outgoing | OUT. | Railway | RY |
| Outlet | OUT. | Reactor | REAC |
| Output | OUT. | Receiver | REC |
| Outside Diameter | OD | Receptacle | RECP |
| Outside Radius | OR | Rectifier | RECT |
| Overload | OVLD | RED | RED |
| Overvoltage | OVV | Refrigerate | REFR |
| Regulator | REG | ||
| Page | PG | Relay | REL |
| Pair | PR | Release | REL |
| Panel | PNL | Remote Control | RC |
| Parallel | || or PAR. | Repeating | RPTG |
| Part | PT | Resistance | RES |
| Passenger | PSGR | Resistor | RES |
| Permanent Magnet | PM | Reverse | REV |
| Perpendicular | _|_ or PERP | Revolution | REV |
| Pickup | PU | Revolutions/Minute | RPM |
| Pilot | PLT | Revolutions/Second | RPS |
| Pint | PT | Rheostat | RHEO |
| Plate | PL | Right | RT |
| Plug | PL | Right Hand | RH |
| Point | PT | Right of Way | R/W |
| Point of Comp. Curve | PCC | Ringing | RING. |
| Point of Curve | PC | Road | RD |
| Point of Frog | PF | Rotary | ROT. |
| Point cf Intersection | PI | Route | RTE |
| Point of Reverse Curve | PRC | ||
| Point of Spiral Tangent | PST | Schedule | SCH |
| Point of Switch | PS | Schematic | SCHEM |
| Point of Tangent | PT | Screw | SCR |
| Polar(ized) | POL | Second (ary) | SEC |
| Pole | P | Section | SECT |
| Positive | + or POS | Segment | SEG |
| Potential | POT | Select | SEL |
| Potentiometer | POT | Selsyn | SELS |
| Pound | LB | Sequence | SEQ |
| Pounds/Square Inch | PSI | Series | SER |
| Power | PWR | Shop Order | SO |
| Power Amplifter | PA | Shunt | SH |
Abbreviations - Si thru Z and Notes
| Siding | SDG | Transportation | TPN |
| Signal | SIG | Trip Coil | TC |
| Single | S | Triple Pole Switch | SPSW |
| Sketch | SK | Triple Pole Single Throw | 3PSTSW |
| Slow Release | SR | Triple Pole Double Throw | 3PDTSW |
| Solder | SLD | Trunk | TRK |
| Solenoid | SOL | Turn Table | TT |
| South | S | ||
| Spare | SP | Ultra High Frequency | UHF |
| Speaker | SPKR | Universal | UNIV |
| Special | SPL | Up | UP |
| Specification | SPEC | ||
| Speed | SP | Vacuum | VAC |
| Spring | SPG | Vacuum Tube | VT |
| Square | SQ | Variable | VAR |
| Standard | STD | Versus | VS |
| Station | STA | Vertical | VERT |
| Stock | STK | Vibrate | VIB |
| Straight | STR | Volt | V |
| Street | ST | Voltage Relay | VR |
| Substation | SUB STA | Voltampere | VA |
| Superimposed Current | SC | Voltmeter | VM |
| Superintendent | SUPT | Volume | VOL |
| Supplement | SUPP | ||
| Switch | SW | Warehouse | WHSE |
| Single Pole | SPSW | Water Plug | WP |
| Single Pole Single Throw | SPSTSW | Water Tank | WT |
| Single Pole Double Throw | SPDTSW | Water Tower | WT |
| Double Pole | DPSW | Watt | W |
| Double Pole Single Throw | DPSTSW | Watt Hour | WHR |
| Double Pole Double Throw | DPDTSW | Watt Hour Meter | WHM |
| Triple Pole | 3PSW | Watt Meter | WM |
| Triple Pole Single Throw | 3PSTSW | Week | WK |
| Triple Pole Double Throw | 3PDTSW | Weight | WT |
| Switchboard | SWBD | West | W |
| Symbol | SYM | Wheelbase | WB |
| System | SYS | White | WHT |
| Width | W | ||
| Tabulate | TAB | Wire | W |
| Telegraph | TLG | Wire Way | WW |
| Telephone | TEL | ||
| Terminal | TERM | Yard | YD |
| Thousand (See Note) | K | Year | YR |
| Throttle | THROT | Yellow | YEL |
| Through | THRU | ||
| Ticket | TKT | ||
| Time | T | ||
| Toggle | TGL | ||
| Tower | TWR | ||
| Track | TK | ||
| Train | TRN | ||
| Transfer | TRANS | ||
| Transformer | TRANS | ||
| Transmitter | XMTR |
NOTE: "K" will be the new symbol for thousand (1,000). It is derived from Kilo; ie., kilovolt equals 1000 volts.
Example: 50KV equals 50 thousand volts.
"M" will be the new symbol for million (1,000,000). It is derived from Mega; ie., Megacycle
equals 1,000,000 cycles.
Example: 50 MC equals 50 million cycles.