k | kilo (1000) |
K | kelvin |
kA | kiloampere |
KB | kilobyte (210 bytes) |
kg | kilogram |
kg/cm2 | kilograms per square |
| centimeter |
kgm | |
kg/m3 | kilograms per cubic meter |
kHz | kilohertz |
kJ | kilojoule |
km | kilometer |
kOhm, k | |
kPa | kilopascal |
kph | kilometers per hour |
kV | kilovolt |
kVA | kilovolt ampere |
kVAR | kilovolt ampere reactive |
kW | kilowatt |
kWh | |
kWm | kilowatt mechanical |
L | liter |
LAN | local area network |
L x W x H | length by width by height |
lb. | pound, pounds |
lbm/ft3 | pounds mass per cubic feet |
LCB | line circuit breaker |
LCD | liquid crystal display |
ld. shd. | load shed |
LED | light emitting diode |
Lph | liters per hour |
Lpm | liters per minute |
LOP | low oil pressure |
LP | liquefied petroleum |
LPG | liquefied petroleum gas |
LS | left side |
Lwa | sound power level, A weighted |
LWL | low water level |
LWT | low water temperature |
m | meter, milli (1/1000) |
Mmega (106 when used with SI units), male
m3 | cubic meter |
m3/min. | cubic meters per minute |
mA | milliampere |
man. | manual |
max. | maximum |
MB | megabyte (220 bytes) |
MCM | one thousand circular mils |
MCCB | |
meggar | megohmmeter |
MHz | megahertz |
mi. | mile |
mil | one |
min. | minimum, minute |
misc. | miscellaneous |
MJ | megajoule |
mJ | millijoule |
mm | millimeter |
mOhm, m | |
| milliohm |
MOhm, M | |
| megohm |
MOV | metal oxide varistor |
MPa | megapascal |
mpg | miles per gallon |
mph | miles per hour |
MS | military standard |
m/sec. | meters per second |
MTBF | mean time between failure |
MTBO | mean time between overhauls |
mtg. | mounting |
MW | megawatt |
mW | milliwatt |
F | microfarad |
N, norm. | normal (power source) |
NA | not available, not applicable |
nat. gas | natural gas |
NBS | National Bureau of Standards |
NC | normally closed |
NEC | National Electrical Code |
NEMA | National Electrical |
| Manufacturers Association |
NFPA | National Fire Protection |
| Association |
Nm | newton meter |
NO | normally open |
no., nos. | number, numbers |
NPS | National Pipe, Straight |
NPSC | National Pipe, |
NPT | National Standard taper pipe |
| thread per general use |
NPTF | National Pipe, |
NR | not required, normal relay |
ns | nanosecond |
OC | overcrank |
OD | outside diameter |
OEM | original equipment |
| manufacturer |
OF | overfrequency |
opt. | option, optional |
OS | oversize, overspeed |
OSHA | Occupational Safety and Health |
| Administration |
OV | overvoltage |
oz. | ounce |
p., pp. | page, pages |
PC | personal computer |
PCB | printed circuit board |
pF | picofarad |
PF | power factor |
ph., | phase |
PHC | Phillips head crimptite (screw) |
PHH | Phillips hex head (screw) |
PHM | pan head machine (screw) |
PLC | programmable logic control |
PMG | |
pot | potentiometer, potential |
ppm | parts per million |
PROM | programmable |
| memory |
psi | pounds per square inch |
pt. | pint |
PTC | positive temperature coefficient |
PTO | power takeoff |
PVC | polyvinyl chloride |
qt. | quart, quarts |
qty. | quantity |
Rreplacement (emergency) power source
rad. | radiator, radius |
RAM | random access memory |
RDO | relay driver output |
ref. | reference |
rem. | remote |
Res/Coml | Residential/Commercial |
RFI | radio frequency interference |
RH | round head |
RHM | round head machine (screw) |
rly. | relay |
rms | root mean square |
rnd. | round |
ROM | read only memory |
rot. | rotate, rotating |
rpm | revolutions per minute |
RS | right side |
RTV | room temperature vulcanization |
SAE | Society of Automotive |
| Engineers |
scfm | standard cubic feet per minute |
SCR | silicon controlled rectifier |
s, sec. | second |
SI | Systeme international d’unites, |
| International System of Units |
SI/EO | side in/end out |
sil. | silencer |
SN | serial number |
SPDT | |
SPST | |
spec, specs | |
| specification(s) |
sq. | square |
sq. cm | square centimeter |
sq. in. | square inch |
SSstainless steel
std. standard
stl. steel
tach. tachometer
TD | time delay |
TDC | top dead center |
TDEC | time delay engine cooldown |
TDEN | time delay emergency to |
| normal |
TDES | time delay engine start |
TDNE | time delay normal to |
| emergency |
TDOE | time delay off to emergency |
TDON | time delay off to normal |
temp. | temperature |
term. | terminal |
TIF | telephone influence factor |
TIR | total indicator reading |
tol. | tolerance |
turbo. | turbocharger |
typ. | typical (same in multiple |
| locations) |
UF | underfrequency |
UHF | ultrahigh frequency |
UL | Underwriter’s Laboratories, Inc. |
UNC | unified coarse thread (was NC) |
UNF | unified fine thread (was NF) |
univ. | universal |
US | undersize, underspeed |
UV | ultraviolet, undervoltage |
V | volt |
VAC | volts alternating current |
VAR | voltampere reactive |
VDC | volts direct current |
VFD | vacuum fluorescent display |
VGA | video graphics adapter |
VHF | very high frequency |
W | watt |
WCR | withstand and closing rating |
w/ | with |
w/o | without |
wt. | weight |
xfmr | transformer |