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<br /> ��� _ �� ���,Page 4$of 51 �, �08/24/201��
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<br /> �ypes of Switches across a tungsten filament.Such capacity is already inherent in the
<br /> Switches used in branch circuit wiring are rated in two general cate- design ofAC Quiet switches. o
<br /> gories:AC ONLY and AC/DC.Originally,the electrical power fumished AC/DC switches are rated at only 50/a of their current capacity for motor
<br /> to residences and businesses by utility companies was Direct Current loads.A20 amp AC/DC switch could be used to control a 10 amp motor
<br /> or DC.Because DC current was alwa�ys flowing at full value,the making load,while a 20 ampAC Quiet switch can operate a 16 amp motor load.
<br /> or breaking of a circuit created a rather strong arc during switch opera- In the past,MERCURY switches were available that operated by mak-
<br /> tion.For this reason,the contacts had to be widely gapped and the ing and breaking contact within a hermetically sealed capsule contain-
<br /> operation had to be"quick make,quick break"to avoid excessive pitting ing a pool of inercury.MERCURY switches were actually silent in
<br /> or welding of the contact points. ope[ation.However,due to health concems about mercury,these
<br /> Altemating current operates befiveen zero and full power 120 times per switches are no longer manufactured and sold.MERCURY switches
<br /> second.Because of the oscillating characteristic ofAC power,the arc may still be in service in some installations
<br /> from an AC circuit is self-extinguishing on the"break"of the current. Horse owsr Ratin s
<br /> This means a slower breaking action is possible on an AC switch,as P J
<br /> opposed to the breaking action required of a switch made for use with Switches marked with Horsepower(HP)Ratings are suitable for con-
<br /> continuous full-power DC. The pulsating nature ofAC can,however, trolling the motor loads of the HP ratings shown on the switch,as weil
<br /> cause a"chattering"or very fast series of"makes"and"breaks"if the as loads with a lower HP rating.
<br /> circuit is closed too quickly.For this reason an AC ONLY switch works To qualify for an HP rating,a switch is tested at six times the full motor
<br /> with a somewhat slower"fast make"and"break"than an AC/DC switch. load current corresponding the HP rating marked on the switch.For
<br /> Because the make and break actions of an AC/DC switch must be fast, DC motor load controllers,the test is made at 10 times the full motor
<br /> it can be rather noisy,and must use contact metals capable of enduring load current corresponding to the DC HP rating marked on the switch.
<br /> such comparatively violent action while still offering acceptable electri- The test is conducted on six samples and consists of 50 On-Off opera-
<br /> cal conductivity.An alloy of copper is most often used. tions at the load.For a 3/a HP rating at 120/240 V AC,two sets of six
<br /> Silver and its oxides are better conductors than oopper and its oxides. samples each are tested in addition to the regular overioad endurance,
<br /> Silver is much softer than copper and therefore cannot be used in the heating and insulation tests.The test circuit characteristics are:
<br /> AC/DC switch.However,silver can be used in the AC ONLY switch For 31a HP Rating Eor 3la HP
<br /> because of its gentler"fast make"characteristic,especially when silver @ 72o v AC @ 240 v AC
<br /> is alloyed with cadmium oxide,a good conductor thaYs quite hard. Closed Circuit volts 120 V AC 24o V AC ;.
<br /> �y�dgg�h Rdt�nf�g Current 82.8 amps 41.4 amps <
<br /> AC ONLY switches are often called AC Quiet switches because they Power.Pactor o.�40-0:50 0;40-0.50 '
<br /> can be made to operate very quietly,unlike AC/DC switches.AC ONLY Note:The current at 240 VAC is�/z that at 120 VAC „
<br /> switches are rated at their full current value for lighting,including tung- All switches must be in good operating condition after the tests have
<br /> sten filament,quartz metal-halide,and fluorescent;and 80°/a current been completed.There must be no excessive arcing,welding or bum-
<br /> value or full horsepower rating value for motor(inductive)loads. ing of the contacts nor arc-over to ground(the switch frames are
<br /> AC/DC switches used for incandescent lighting should have a"T"rating 9rounded during the Stalled Rotor Test).
<br /> (tungsten-filament rating).The"T"raUng assures end-users of the
<br /> longevity of the switch through the surge currents of a"make"action
<br /> ' Industry`�tan�lards for;•Electr�cai�firin �evices ' -
<br /> ;,;. � � � .
<br /> National Electr�cal�ade Requiremer�ts�for Sw�tches-I�ationai Elecfrical Co�e NfPA'No.70-7H96,(Selectet!Articles)
<br /> �-�� �, ,
<br /> ;Anc�le�8U Swi#ches 380� ' Facepiates fwr Flush Mounted
<br /> �, -i. 38D"I Sco e s,£�� � ' � �� r: Snap Switches >� + ••
<br /> 38Q 2 5wi�ch Connectionsr ' ;` 3�Q-'14� ' Rating antl Useof:�nap Switches '
<br /> 38CT-8 .,� Accessib3lity and Grouping ' 380-�5, ` AAarking , t �; " , "
<br /> Ca00SS21'y Momentary Contact—A switch that makes circuit contact only as long as the actuator
<br /> (toggle,rocker,pushbutton or key mechanism)is held in the ON posi6on,after which it
<br /> ACIDC—Aswitch designated for use wiTh e'dherAitemating Current(AC)or Direct Current(DC) retums automadcally to the OFF position.This is a"Normally Open"switch.A"Normally
<br /> �AC Only—Aswitch designated for use with Altemating Current(AC)only. Closed"switch will break cirouit contact as long as it is hetd in the OFF posiGon,and then
<br /> Dimmer—Aswitch with electronic dreuitry fhat provides DIMBRIGHT control of lighting loads. automatically retum to the ON posiGon.Available in"Center OFF"versions with both
<br /> Door—A momentery contact switch,usually installed on a doo�amb,that is activated when Momentary ON and Momentary OFF positions.
<br /> the door is opened or closed. Pendant—Atype of switch designed for insfalla6on at ihe end of a length of portable cord or cable,�
<br /> Double�ole,Single•Throw�DPSn—Aswitchihatmakesorbreaksttieconneclionoftwodreuit pilotLight—Aswitchwithanintegrallampinifsachuafnr(toggle,rodcerorpushbutton)thatillumi-
<br /> conductors in a single brench circ;uit.This switch has four tertninal screws and ON/OFF inaricings. nates when the switch is connected to an energized arcuft and the acWator is in the ON position.
<br /> � Double•Pole,Double-Throw(DPD�—Aswitch that makes or breaks the connection of two. Pull—A switch where the making or breaking of confacts is controlled by pulling downward or
<br /> � � conductors to two separate circuits.This switch has six terminal screws and is available in both ou�waM�on the actuator mechanism.. � �. �
<br /> � momentary and maintained contact.versions,and may also have a center OFF position. push Button—A switch with an actuator mechanism that is operated by
<br /> � � Feed Through—An in-line switch that can be attached at any point on a length of Flexible cord depressing a button. �
<br /> � to provide swdching conVol of attached equipment Rotary—Aswitch where rotating the actuator in a clockwise direction makes the arcuit conneo-
<br /> Flush�AAomNed—Aswitch designed forflush installation with ttie surface of a panel or equipment lion,and then rotating�the aduator in either the same or opposite direcfion breaks the connedion.
<br /> Four-Way—Aswitch used in conjunction with lwo 3-Way switches to control a single load Single�Pole,Double Throw(SPDn—Aswitch that makes or breaks ihe connection of a sin-
<br /> (such as a light fixture)from three or more Iocations.This switch has four tertninal screws and gle conductorwith either oftwo other single conductors.This switch has 3 tertninal screws,and
<br /> no ON/OFF inarking. is commonly used in pafrs and called a"Thre�Way'switch.
<br /> Horsepower Rated—A switch with a marked horsepower reting,intended for use in swi[ching Single-Pole,Single-Throw(SPS7)—A switch that makes or breaks the
<br /> � motor loads. connection of a single conductor in a single branch circuit.This switch has two screw tertni-
<br /> Interchangeable—A switch or combination of swiU�es with a common mourrting dimension nals and ON/OFF designations.It is commonly referred to as a"Single-Pole"Switch.
<br />� � that may be installed on a single or multiple-opening mounting sUap. Slide—A switch with a slide-action actuatorfor making or breaking circuit contact.Dimmer
<br /> Lighted Handle—A switch with an integral lamp in its actuator(toggle,rocker or pushbutton) switches and fan speed conhols are also available with slide-action mechanisms for lighting
<br /> that illuminates when the switch is connected to an energized circuit and the actuator is in the and fan speed control � �
<br /> OFF position. . � Surfaceadounted—Any switch that mounts on a flat or plane surface.
<br /> Locking—A switch equipped with a locking mechanism that requires a key to operate the Three-Position,Center OFF—A two circuit switch,either maintained or momentary contact,
<br /> switching functions. � where fhe OFF position is designated as the center posilion of the actuator.
<br /> _ Low-Vokage—A switch rated for use on low-vdtage arcuits of 50 volts or less. � Three-Way—Aswitch,always used in pairs,that controls a single load such as a light fiMure
<br /> L-Rated—A switch specially designated with the letter"L"in its ra6ng that is rated for control- from two locations.This switch has three tertninal screws and has no ON/OFF inarking.
<br /> ling tungsten filament lamps onAC circuits only. Time Delay—A switch with an integral mechanism or electronic circuit tliat will automatirally
<br /> MainWined Contact—Aswitch where the aclualor(toggle,rocker,pushbutton or key mecha- switch a load OFF at a predetertnined tlme interval.
<br /> nism)makes and retains dreuit confact when moved to the ON posilion.The contacfs will only Timer—Aswitch with an integrai mechanism or electronic arcuit that can be set to switch an
<br /> be opened when the actuator is manually moved to the OFF position.Ordinary light switches electrica�load ON at a predetertnined time.
<br /> are maintained confact swftches. � Toggle—A switch with a lever-rype actuator ttiat makes or breaks switch wntact as its.posibon �
<br /> � Manual Motor ConGoller—Aswitch designed for controlling small DC orAC motor loads, is changed.
<br /> without overload protection. T-Rated—A switch specially designated with the letter'T"in its rating that is rated for conVol-
<br />� Mercury—Atype of switch that uses mercury as the contact means for making and breaking ling tungsten filament lamps on direct current(DC)or altemating cunent(AC)circuits.
<br /> an electrical cirouit. � �
<br /> To learn more about Ceviton devices or for answers to technical questions call our Techline at ��:=1-800-824-3005 or visit us at:� wwwtle�iton.com ,
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