LINEMASTER Switch Corporation - Glossary of Frequently Used Terms


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Glossary Definitions of Frequently Used Terms
0-9 · A · B · C · D · E · F · G · H · I · J · K · L · M · N · O · P · Q · R · S · T · U · V · W · X · Y · Z
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Agency Symbols TOP
Term	Defintion
	SEV Accepted Schweizerischer Electrotechnischer Verein (SEV) is the certification agency for Switzerland. The recognized association for Swiss standards is the Swiss Standards Association (SEV). The SEV has adopted IEC standards almost without exception. The SEV mark molded into a plug or connector indicates that a product has been tested and approved for use in Switzerland. All products to be sold in Switzerland must bear this mark.
	AP Marked
	CE MARKED http://www.ce-marking.org
	CSA Certified http://www.csa.ca
	DEMKO Recognized Component UL International Demko A/S certificate and the D-Mark The D-Mark signals to consumers, retailers, insurers and authorities that a reputable, independent third-party and European National Certification body has tested the product to appropriate international, electrical safety standards. The D-Mark is a voluntary safety mark registered and provided by UL-Demko. It has been in use for more than 70 years and is a familiar symbol to consumers as well as retailers and manufacturers in Europe.
	UL Recognized Component Mark Recognized Component Mark This is a mark consumers rarely see because it is specifically used on component parts that are part of a larger product or system. These components may have restrictions on their performance or may be incomplete in construction. The Component Recognition marking is found on a wide range of products, including some switches, power supplies, printed wiring boards, some kinds of industrial control equipment and thousands of other products. http://www.ul.com
	UL Recognized Component Mark for Canada and the United States Recognized Component Mark for Canada and the United States This new UL Recognized Component Mark, which became effective April 1, 1998, may be used on components certified by UL to both Canadian and U.S. requirements. Although UL had not originally planned to introduce a combined Recognized Component Mark, the popularity of the Canada/U.S. Listing and Classification Marks among clients with UL certifications for both Canada and the United States has led to the new Mark. http://www.ul.com
	TUV BAUART
	UL Mark UL Listing Mark This is one of the most common UL Marks. If a product carries this Mark, it means UL found that representative samples of this product met UL's safety requirements. These requirements are primarily based on UL's own published Standards for Safety. This type of Mark is seen commonly on appliances and computer equipment, furnaces and heaters, fuses, electrical panelboards, smoke and carbon monoxide detectors, fire extinguishers and sprinkler systems, personal flotation devices like life jackets and life preservers, bullet resistant glass, and thousands of other products. http://www.ul.com
LISTED	UL Mark for Canada and the United States C-UL US Listing Mark UL introduced this new Listing Mark in early 1998. It indicates compliance with both Canadian and U.S. requirements. The Canada/U.S. UL Mark is optional. UL encourages those manufacturers with products certified for both countries to use this new, combined Mark, but they may continue using separate UL Marks for the United States and Canada. http://www.ul.com
	Symbol for WEEE Compliance
0-9 TOP
Term	Defintion
2-Way	Air valve either on or off -- spring return (momentary) action.
3-Way	Air valve either on or off with exhaust -- spring return (momentary) action.
4-Way	Air Valve with N.O. and N.C. flow and exhaust -- spring return (momentary) action.
A TOP
Term	Defintion
A	A symbol designation for ampere.
AC ~	Alternating Current (AC)
Alternating Current (AC)	Electric Current that alternates or reverses polarity continuously. The number of alternations per second is described as cycles, (hertz or Hz). The rate at which a full cycle occurs in a given unit of time (generally a second) is called the frequency of the current.
American Wire Gauge (AWG)	A standard for expressing wire diameter. As the AWG number gets smaller, the wire diameter gets larger.
AMP	Ampere
Ampacity	The current in amperes that a conductor can carry continuously under the conditions of use without exceeding its temperature.
Ampere	A standard unit of electrical current flow. Defined as the amount of current that flows when one volt of emf is applied across one ohm of resistance. An ampere of current is produced by one coulomb of charge passing a point in one second.
ANSI	American National Standards Institute.
AP	Category AP Equipment: Equipment or equipment part complying with specified requirements on construction, marking and documentation in order to avoid sources of ignition in a flammable anesthetic mixture with air.
Auxiliary Contact	Contacts of a switching device in addition to the main current contacts that operate with the movement of the latter. They can be normally open (NO) or normally closed (NC) and change state when operated.
AWG	American Wire Gauge (AWG)
B TOP
Term	Defintion
BBM	Break-Before-Make
Bifurcated Contacts	A movable contact which is constructed to provide two contact mating surfaces in parallel for more reliable contact.
Braid	A group of metallic filaments interwoven to form a tubular flexible structure which may be applied over one or more wires.
Break	An opening or interruption of a circuit.
Break-Before-Make	The movable contact breaks one circuit before making the next circuit.
C TOP
Term	Defintion
CE	Conformiteé Européenne (European Conformity). http://www.ce-marking.org
CFM	Cubic feet per minute
Common	Interior switch terminal of the moving contact member.
Contact Bounce	Rebounding of moving contact against fixed contact during transfer.
Cord	A flexible insulated cable.
CSA	Canadian Standards Association. This is a nonprofit, independent organization that operates a listing service for electrical materials and equipment in the Canadian counterpart of the Underwriters Laboratories. http://www.csa.ca
Cubic feet per minute	An airflow measurement of volume.
D TOP
Term	Defintion
D	Denmark approval Agency symbol: DEMKO
DB	Double Break
DC	Direct Current (DC)
Dia.	Diameter.
Diameter	A straight line segment that passes through the center of a circle or sphere with both of its ends on the boundary.
Direct Current (DC)	Electrical current whose electrons flow in one direction only. It maybe constant or pulsating as long as its movement is in the same direction.
Double Break	A form of contact construction in which a current carrying member bridges a gap in an otherwise complete circuit, thus breaking the current at two adjacent points, one at each end of the bridging member. This breaks the circuit in two places. Also referred to as Form Z circuitry.
Double Pole	A switching device that has more than one pole or two poles is called double pole. Switches which make and break two separate circuits.
Double Pole Double Throw	A term used to describe a switch or relay output contact Form (Form CC) in which two separate switches are operating simultaneously, each with a normally open and normally closed contact and a common connection. This form is used to make and break two separate circuits.
DPDT	Double Pole Double Throw
DRIPTIGHT	Constructed or protected as to exclude falling dirt or drops of liquid under specified test conditions.
DUSTTIGHT	Constructed as to meet the requirements of a specified dusttightness test.
E TOP
Term	Defintion
EC	European Community
EN	European Norm: Harmonized Standards written by European standards organizations.
EN 60529	European Standard: “Degrees of Protection Provided by Enclosures (IP code)”.
F TOP
Term	Defintion
FDA	Food and Drug Administration (FDA). http://www.fda.gov
Foot Switch	A switch which is suitable for operation by an operator's foot.
FORM A (SPST-NO)	An industry abbreviation for a Single Pole Single Throw Normally Open Contact. The contacts of a Form A switch close upon actuation.
FORM B (SPST-NC)	An industry abbreviation for a Single Pole Single Throw Normally Closed Contact. The contacts of a Form B switch open upon actuation.
FORM C (SPDT)	An industry abbreviation for a Single Pole Double Throw set of contacts. A form C switch has two contacts - one that opens and one that closes upon actuation.
FORM Z	Double Break Circuit - (Twin Break) This Breaks the circuit in two places. Referred to as Double Break Contacts.
G TOP
Term	Defintion
Gauge	The physical diameter of a wire. A standard for expressing wire diameter. As the AWG number gets smaller, the wire diameter gets larger.
Grounding Conductor	The green/yellow colored conductor used to connect the non-current carrying metal parts and metal enclosure to the system grounded conductor.
H TOP
Term	Defintion
Hertz (Hz)	The number of changes in polarity which a signal makes in one second. An indication of frequency. Replaces cycles-per-second.
HP	Horsepower
Hypot	A test designed to determine the highest potential that can be applied to a conductor without breaking through the insulation.
HZ	Hertz
I TOP
Term	Defintion
ID	Inside Diameter
IEC	International Electromechanical Commission.
IEC 60601-2-2	IEC 60601-2-2 - European Standard: “Medical Electrical Equipment - Part 2-2: Particular Requirements for the Safety of High Frequency Surgical Equipment”.
Insulated Wire	A conductor of electricity covered with a nonconducting material.
Insulation	A material having good dielectric properties which are used to separate close electrical components, such as cable conductors and circuit components.
International Electromechanical Commission (IEC)	A European group consisting of multi-national representatives which develop standards for electrical components.
International Standards Organization (ISO)	The International Organization for Standardization (ISO) is a worldwide federation of national standards bodies from more than 140 countries, one from each country. ISO promotes the development of standardization and related activities in the world with a view to facilitating the international exchange of goods and services, and to developing cooperation in the spheres of intellectual, scientific, technological and economic activity. http://www.iso.org
IP	Ingress Protection Ratings: A coding system to indicate the degree of protection provided by an enclosure against access to hazardous parts, ingress of solid foreign objects, ingress of water and to give additional information in connection with such protection. See IP Code Chart
IP20	Protection against solid foreign objects of 12.5 mm in diameter and greater. See IP Code Chart
IP40	Protection against solid foreign objects of 1.0 mm in diameter and greater. See IP Code Chart
IP56	Dust protected and protected against powerful water jets. See IP Code Chart
IP65	Dusttight and protected against water jets. See IP Code Chart
IP67	Dusttight and protected against the effects of temporary immersion in water. See IP Code Chart
IP68	Dusttight and protected against the effects of continuous immersion in water. See IP Code Chart
IPXX	When a characteristic numeral is not required to be specified, it is replaced by the letter “X”. (“XX” when both numerals are omitted). See IP Code Chart
IR	Infrared transmission means of wireless control.
ISO	International Standards Organization.
J TOP
Term	Defintion
Jacket	An extruded layer of insulation over a wire or group of cables.
Jumper	A short length of conductor used to make a connection between terminals.
K TOP
Term	Defintion
K	Symbol for one thousand, used in describing value of poteniometer in Ohms, 5K is 5 thousand.
L TOP
Term	Defintion
LBS	Pounds
Linear	Device having an output that is proportional to the input, used in describing the action of a variable control foot switch.
M TOP
Term	Defintion
mA	milliampere
mA	Milliamps
Maintained	Press - on, Press again - off. When a maintained action switch is actuated, the contacts move to transfer the circuits to the second set of contacts. No change takes place with the contacts when the operator removes his or her foot even though the actuator, treadle or cover, has returned to the original position. When the operator actuates the switch a second time, the contacts returns to the original position. The maintained Hercules models utilize a latching mechanism with a "Press-On, Release Latch-Off" operation. To release the latch, the operator must move their foot in a forward lateral movement against a kick-plate. The maintained Treadlite II models utilize a detent action of the cover (over-center rocking action) to provide the maintained function. In Linemaster numbers, the letter :D: used in the suffix denotes maintained action.
Make	The closing or completion of a circuit.
Make-Before-Break	The movable contact makes the next circuit before breaking the first circuit.
Material Safety Data Sheets	A Material Safety Data Sheet (MSDS) is designed to provide both workers and emergency personnel with the proper procedures for handling or working with a particular substance. MSDS's include information such as physical data (melting point, boiling point, flash point etc.), toxicity, health effects, first aid, reactivity, storage, disposal, protective equipment, and spill/leak procedures. These are of particular use if a spill or other accident occurs.
MBB	Make-Before-Break
Mechanical Interlock	A device so designed as to allow the operation only in a prearranged sequence.
Megahertz (MHz)	Unit of frequency equal to one million hertz (one million hertz per second).
MEGOHMS	Resistance in millions of Ohms.
MHz	Megahertz
milliampere	one-thousandth of an ampere
Momentary	Press - on, release - off. When a momentary action switch is actuated, the actuating device, treadle or cover, and contacts move to transfer the circuits to a second set of contacts. When the actuating force is removed, the actuating device and the contacts return to the original position.
M.S.D.S.	Material Safety Data Sheets
M20	Metric thread size
N TOP
Term	Defintion
NC	Normally Closed Circuit
NC	Unified National Coarse Thread (National Coarse)
NEMA	National Electrical Manufacturers Association. http://www.nema.org
Neoprene	A synthetic rubber with good resistance to oil, chemical, and flame. Also called polychloroprene.
NF	Unified National Fine Thread (National Fine)
NFPA	National Fire Protection Association. http://www.nfpa.org
NO	Normally Open Circuit
Normally Closed Circuit	1) An electrical circuit in which current normally flows until interrupted by the opening of a switch or a switch-type electronic component.
Normally Closed Circuit	2) A circuit or switch in which the contacts are closed during normal operation
Normally Open Circuit	1) An electrical circuit in which current does not flow until permitted by the closing of a switch or a switch-type electronic component.
Normally Open Circuit	2) A circuit or switch in which the contacts are open during normal operation
NPT	National Pipe Tapered Threads Standard, FIP, MIP
O TOP
Term	Defintion
OD	Outside Diameter
OEM	Original Equipment Manufacturer
Ohm	The unit of electrical resistance. The value of resistance through which a potential difference of one volt will maintain a current of one ampere.
Ohm's Law	Stated E=IR, I=E/R or R=E/I, the current I in a circuit is directly proportional to the voltage E, and inversely proportional to the resistance R.
OILTIGHT	Constructed as to exclude test liquid applied in the form of a stream under specified test conditions.
OZ	Ounce
P TOP
Term	Defintion
PG	European threaded conduit entry, i.e. PG16.
Pinch Point	Any point at which it is possible for a portion of the body to be caught and injured between moving machine or equipment or work piece parts.
Plastic	High polymeric substances, including both natural and synthetic products that are capable of flowing under heat and pressure, called thermoplastics. Unlike rubber and other thermoset compounds, plastics can be remelted and reused.
PLC	Programmable Logic Controller
Plug	A male housing with male or female contacts.
Pneumatic	Operate by air pressure.
Point Of Operation	The point or area of the machine or equipment where the work piece or material is actually positioned and work is being performed during any process such as cutting, shearing, punching, forming, welding, riveting, assembling, etc.
Pole	That portion of the interior switch associated with one electrically separated conducting path of the main circuit of the interior switch.
Poles	The number of separate circuits which can conduct current through a switch at one time.
Potentiometer	A three terminal device with a wiper that is positioned along a resistive element; effectively making a voltage divider.
Pounds per square inch	Force exerted per unit area.
Power	The amount of work per unit of time. Usually expressed in watts and equal to the formula for power in watts. (I to the second power times R).
PROOF	Proof used as a suffix means so constructed, protected or treated that successful operation of the apparatus is not interfered with when subjected to the specified material or condition.
PSI	Pounds per square inch.
PVC	Polyvinyl chloride. Sometimes referred to as vinyl. Fire resistant.
Q TOP
Term	Defintion

R TOP
Term	Defintion
R	Symbol for resistance.
RAINPROOF	Rainproof means so constructed, protected or treated as to prevent rain under specified test conditions from interfering with successful operation of the apparatus.
Rated Voltage	The maximum voltage at which an electric component can operate for extended periods without undue degradation or safety hazard.
Receptacle	A female housing with male or female contacts.
Resistance	In DC circuits, the opposition a material offers to current flow, measured in ohms. In ac circuits, resistance is the real component of impedance, and may be higher than the value measured at DC.
RESISTANT	Resistant used as a suffix means so constructed, protected or treated that the apparatus will not be damaged when subjected to the specified material or condition for a specified time.
RoHS	European Directive 2002/95/EC "The restriction of the use of certain hazardous substances in electrical and electronic equipment."
RU	Components Recognized under UL’s Component Recognition and Follow-UP Services are identified by the UL Recognized Marking “RU”.
Rubber (Wire Insulation)	A general term used to describe wire insulations made of thermosetting elastomers, such as natural or synthetic rubbers, neoprene, Hypalon, butyl rubber, and others.
S TOP
Term	Defintion
S	Heavy duty, rubber-insulated portable cord. Stranded copper conductors with separator and individual rubber insulation. Two or more color coded conductors cabled with filler, wrapped with separator and rubber jacketed overall. 600V.
S+	Swiss Testing Agency symbol: SEV
SEOW(-A)	Extra hard service cord. Thermoplastic elastomer, oil resistant (TPE) construction Jacket. 600 volt, weather resistant for outdoor use. (A) -- The "A" has recently been dropped from the description.
Sheath	Pertaining to wire and cable, the outer protective covering (may also provide additional insulation).
Shield	A tape, serve or braid (usually copper, aluminum, or other conductive material) placed around or between electric circuits or cables or their components, to prevent signal leakage or interference.
Single PG	German conduit thread designation “PG”.
Single Pole	A switching device is called single pole if it has only one pole. Switches which make and break a single circuit.
Single Pole Double Throw	A term used to describe a switch contact Form C that has a normally open and a normally closed contact with a common connection.
Single Pole Normally Open	A switch with only one moving and one stationary contact. Also referred as a Form A circuitry.
Single Pole Single Throw	A switch with only one moving and one stationary contact, available either normally open Form A(NO) or normally closed Form B(NC).
Single Stage	Single Function
SJ	Junior hard service, rubber-insulated pendant or portable cord. Same construction as type S, but 300V. Jacket thickness different.
SJEOW(-A)	Extra hard service cord. Thermoplastic elastomer, oil resistant (TPE) construction jacket. 300 volt, weather resistant for outdoor use. (A) -- The "A" has recently been dropped from the description.
SJO	Same as SJ, but neoprene, oil-resistant compound outer jacket. 300V, 60C.
SJT	Junior hard service thermoplastic or rubber-insulated conductors with overall thermoplastic jacket. 300V, 60C to 105C.
SJTO	Same as SJT but oil-resistant thermoplastic outer jacket. 60C.
SJTW	A hard service cord. Thermoplastic constructed jacket. 300 volt, weather resistant for outdoor use.
Snap Action	Switching action of interior switch. The action of the moving contact member that transfer from one position to another at a speed which is independent of the actuator speed.
SO	Hard service cord, same construction as type S except oil-resistant neoprene jacket. 600V, 60C to 90C.
SO-W	Heavy duty type 50-dual rated type W
SPDT	Single Pole Double Throw
SPNO	Single Pole Normally Open
SPST	Single Pole Single Throw
SPT-1	Thermoplastic constructed, parallel jacketed, 300 volt, 2 or 3 conductors, 18 gauge.
SPT-2	Same as SPT-1 but heavier construction. 18-16 gauge.
SPT-3	Same as SPT-2 but heavier construction. 18-10 gauge.
ST	Hard service cord, jacketed, same as type S except all-plastic construction, 600V, 60C to 105C.
STO	Same as ST but with oil-resistant thermoplastic outer jacket. 600V, 60C.
Strip	To remove insulation from a cable or wire.
STW(-A)	Extra hard service cord. Thermoplastic constructed jacket. 600 volt, weather resistant for outdoor use. (A) -- The "A" has recently been dropped from the description.
SV	Vacuum cleaner cord, two or three conductor, rubber-insulated. Overall rubber jacket. For light duty in damp locations. 300V, 60C.
SVO	Same as SV except neoprene jacket. 300V, 60C.
SVT	Same as SV except all-plastic construction. With or without third conductor for grounding purposes only. 300V, 60C to 90C.
SVTO	Same as SVT except with oil- resistant thermoplastic jacket. 60C.
T TOP
Term	Defintion
Terminal	Any device attached to the conductor by crimping, soldering or welding.
Three Stage	One Pedal, Three Functions Actuated Sequentially
TIGHT	Tight used as a suffix means so constructed that the enclosure will exclude the specified material under specified conditions.
TPDT	Triple Pole Double Throw
Triple Pole	A switching device that has more than one pole, or three poles is called triple pole. Switches which make and break three separate circuits.
Triple Pole Double Throw	Triple Pole Double Throw. Switches which make and break three separate circuits. The switch provides a normally open and normally closed contact for each pole.
TUV	German Testing Agency symbol
Two Stage	One Pedal, Two Functions Actuated Sequentially
Type 1	Enclosure Type 1 constructed for indoor use primarily to provide a degree of protection against limited amounts of falling dirt. A Type 1 enclosure may be additionally marked “Indoor Use Only”.
Type 13	Enclosure Type 13 constructed for indoor use primarily to provide a degree of protection against dust, spraying of water, oil and noncorrosive coolant. A Type 13 enclosure is able to be marked “”Driptight” and/or “Dusttight”.
Type 2	Enclosure Type 2 constructed for indoor use primarily to provide a degree of protection against limited amounts of falling water and dirt. A Type 2 enclosure is able to be marked “Driptight”.
Type 3R	Enclosure Type 3R constructed for either indoor or outdoor use primarily to provide a degree of protection against rain, sleet and damage from external ice formation. A Type 3R enclosure may be marked “Rainproof”.
Type 4	Enclosure Type 4 constructed for either indoor or outdoor use primarily to provide a degree of protection against windblown dust and rain, splashing water, hose directed water and damage from external ice formation. A Type 4 enclosure may be marked “Raintight” and/or “Watertight”.
Type 4X	Enclosure Type 4X constructed for either indoor or outdoor use primarily to provide a degree of protection against corrosion, windblown dust and rain, splashing water, hose directed water and damage from external ice formation. A Type 4X enclosure may be marked “Raintight” and/or “Watertight” and/or “Corrosion Resistant”.
Type 6	Enclosure Type 6 constructed for either indoor or outdoor use primarily to provide a degree of protection against hose directed water and the entry of water during occasional temporary submersion at a limited depth and damage from external ice formation. A Type 6 enclosure may be marked “Raintight”.
Type 6P	Enclosure Type 6P constructed for either indoor or outdoor use primarily to provide a degree of protection against hose directed water, the entry of water during prolonged submersion at a limited depth and damage from external ice formation. A Type 6P enclosure may be marked “Raintight” and/or “Corrosion Resistant”.
Type 7	Enclosure Type 7 constructed for indoor use in hazardous locations classified as Class I, Division 1, Groups A, B, C or D as defined in NFPA 70.
Type 9	Enclosure Type 9 constructed for indoor use in hazardous locations classified as Class II, Division 1, Groups E, F or G as defined in NFPA 70.
U TOP
Term	Defintion
UC	Unified National Coarse Thread (National Coarse)
UF	Unified National Fine Thread (National Fine)
UL ENCLOSURE	Underwriters Laboratories Enclosure Type
UNC	Unified National Coarse Thread (National Coarse)
Underwriters Laboratories	Abbreviation for Underwriters Laboratories, a nonprofit organization which tests and verifies construction and performance of electronic parts and equipment, including wire and cable. http://www.ul.com
UNF	Unified National Fine Thread (National Fine)
Unified National Coarse Thread (National Coarse)	A standard kind of Coarse straight thread used on fittings, nuts, and bolts.
Unified National Fine Thread (National Fine)	A standard kind of Fine straight thread used on fittings, nuts, and bolts.
V TOP
Term	Defintion
V	Volt
VA	Volt-ampere. A designation of power in terms of voltage and current.
VAC	Volts - Alternating Current
Variable	A quantity or condition, i.e. resistance or speed that is subject to change.
VDC	Volts - Direct Current
Volt	A unit of electromotive force.
Voltage	Electrical potential of electromotive force expressed in volts.
Voltage Rating	The highest voltage at which a device is designed to operate.
W TOP
Term	Defintion
W	Symbol for watt or wattage.
W	UL designation for outdoor-approved flexible cord.
W(-A)	UL designation for outdoor-approved flexible cord. (A) -- The "A" has recently been dropped from the description.
WATERTIGHT	constructed as to exclude water applied in the form of a hose stream under specified test conditions.
Watts	A unit of electrical power.
WEEE	Waste Electrical and Electronic Equipment (WEEE) directive.
Wireless	Foot switch using IR or other means to control equipment without the use of a cordset between the footswitch and the equipment it is operating.
X TOP
Term	Defintion

Y TOP
Term	Defintion

Z TOP
Term	Defintion

LINEMASTER Switch Corporation · 29 Plaine Hill Road · POB 238 · Woodstock, CT 06281-0238 · USA
Tel: 860.974.1000 Fax: 860.974.0691 or Toll-Free Fax 800.974.3668 (USA Only)

Definitions of Frequently Used Terms