The list of electrical abbreviations used in a set of construction drawings varies from office to office. Be sure to check the front section of the drawing set for the abbreviations used within that particular set of drawings.
# | Number |
Ω | Ohm |
Φ | Phase |
A | Amperes |
AC | Alternating Current |
A/C | Air Conditioning |
AFCI | Arc Fault Circuit Interrupter |
AHU | Air Handling Unit |
AIC | Ampere Interrupting Capacity |
AL | Aluminum |
ATS | Automatic Transfer Switch |
ATC | Automatic Temperature Control |
AWG | American Wire Gauge |
BTU | British Thermal Units |
C | Conduit |
CATV | Cable Television or Community Antennae Television |
CB | Critical Branch |
C/B | Circuit Breaker |
CBM | Certified Ballast Manufacturer |
CCT | Circuit (also: CIR, CKT) |
CCTV | Closed Circuit Television |
CD | Candela |
CIR | Circuit (also: CCT, CKT) |
CKT | Circuit (also: CCT, CIR) |
CLF | Current Limiting Fuse |
CPT | Control Power Transformer |
CT | Current Transformer |
CU | Copper |
dB | Decibel |
DC | Direct Current |
DIA | Diameter |
EB | Equipment Branch |
EC | Electrical Code or Electrical Contractor |
EF | Exhaust Fan |
ELEV | Elevator |
EM | Emergency |
EMT | Electrical Metallic Tubing |
EP | Emergency Power |
EPO | Emergency Power Off (Button or Switch) |
EWC | Electric Water Cooler |
F | Fuse |
FA | Fire Alarm |
FAA | Fire Alarm Annunciator |
FLA | Full Load Amperes |
FMC | Flexible Metal Conduit |
G | Ground |
GFCI, GFI | Ground Fault Circuit Interrupter |
GND | Ground |
GRMC | Galvanized Rigid Metal Conduit |
HOA | Hand-Off-Automatic Switch |
HVAC | Heating, Ventilation, Air Conditioning |
HZ | Hertz |
IEEE | Institute of Electrical and Electronic Engineers |
IG | Isolated Ground |
IMC | Intermediate Metal Conduit |
INT | Interlock |
KCMIL | Thousand Circular Mils |
KVA | Kilovolt-Amperes |
KVAR | Kilovolt-Amperes Reactive |
LFMC | Liquid Tight Flexible Metal Conduit |
LTG | Lighting |
LRA | Lock Rotor Amps |
MC | Metal Clad Cable |
MCB | Main Circuit Breaker |
MCC | Motor Control Center |
MCP | Motor Circuit Protection |
MI | Mineral Insulated |
MLO | Main Lugs Only |
MW | Megawatt |
NC | Normally Closed |
NEC | National Electrical Code |
NEMA | National Electrical Manufacturers Association |
NFPA | National Fire Protection Association |
NL | Night Light |
NO | Normally Open or Number |
P | Pole |
PB | Push Button or Panic Button or Pull Box |
PNL | Panel |
PWR | Power |
PT | Potential Transformer |
QTY | Quantity |
REQ | Required |
RCCB, RCB | Residual-Current Circuit Breaker |
RCD | Residual-Current Device |
RMC | Rigid Metal Conduit |
RMS | Root Mean Squared |
RNC | Rigid Non-Metallic Conduit |
RTS | Remote Test Station |
RTU | Roof Top Unit |
SE | Service Entrance |
SEB | Service End Line Box or Service Electrical Box |
SP | Spare |
ST | Shunt Trip |
SW | Switch |
SYM | Symmetrical |
TEL, TELE | Telecommunications, Telephone |
TGB | Telecommunications Grounding Busbar |
TMCB | Thermal Magnetic Circuit Breaker |
UG | Under Ground |
UL | Underwriters Laboratory |
V | Volt |
VA | Volt-Ampere |
VFD | Variable Frequency Drive |
VT | Voltage Transformer |
W | Watt or Wire |
WH | Water Heater |
WP | Weatherproof or Waterproof |
XFMR | Transformer |