QWODZZZRKPLWHFRPLQIRRKPLWHFRP  Resistor Selection Application Notes RESISTO F CTS AN D F CTO Why Watts Must Be Accurately Known WDWHGQRQWHFKQLFDOODQFKDQJHLQ FXUUHQWRUYROWDJHSURGXFHVDPXFK ODUJHUFKDQJH
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QWODZZZRKPLWHFRPLQIRRKPLWHFRP Resistor Selection Application Notes RESISTO F CTS AN D F CTO Why Watts Must Be Accurately Known WDWHGQRQWHFKQLFDOODQFKDQJHLQ FXUUHQWRUYROWDJHSURGXFHVDPXFK ODUJHUFKDQJH

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QWODZZZRKPLWHFRPLQIRRKPLWHFRP Resistor Selection Application Notes RESISTO F CTS AN D F CTO Why Watts Must Be Accurately Known WDWHGQRQWHFKQLFDOODQFKDQJHLQ FXUUHQWRUYROWDJHSURGXFHVDPXFK ODUJHUFKDQJH




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Presentation on theme: "QWODZZZRKPLWHFRPLQIRRKPLWHFRP Resistor Selection Application Notes RESISTO F CTS AN D F CTO Why Watts Must Be Accurately Known WDWHGQRQWHFKQLFDOODQFKDQJHLQ FXUUHQWRUYROWDJHSURGXFHVDPXFK ODUJHUFKDQJH"— Presentation transcript:


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Derating )LJVKRZVWKHSHUFHQWRIIXOOORDGZKLFKSRZHUUHVLVWRUVFDQ GLVVLSDWHIRUYDULRXVKLJKDPELHQWWHPSHUDWXUHV Derating Due to Enclosure 7KHDPRXQWRIGHUDWLQJUHTXLUHGLIDQ\EHFDXVHRIHQFORVXUH LVDIIHFWHGE\DQXPEHURIIDFWRUVPRVWRIZKLFKDUHKDUGWR

GHWHUPLQHDFFXUDWHO\7KHZDWWVSHUVTXDUHLQFKRIVXUIDFH VL]HVKDSHRULHQWDWLRQZDOOWKLFNQHVVPDWHULDOILQLVKDQG DPRXQWDQGORFDWLRQRIYHQWLODWLQJRSHQLQJVDOOSOD\DSDUW)LJ VHUYHVWRLQGLFDWHIRUDSDUWLFXODUVHWRIFRQGLWLRQVKRZWKH

WHPSHUDWXUHVYDULHGZLWKWKHVL]HRIHQFORVXUHIRUDPRGHUDWH VL]HSRZHUUHVLVWRU Derating Due to Grouping 7KHWHPSHUDWXUHULVHRIDFRPSRQHQWLVDIIHFWHGE\WKHQHDUE\ SUHVHQFHRIRWKHUKHDWSURGXFLQJXQLWVVXFKDVUHVLVWRUVHOHF

WURQLFWXEHVHWF7KHFXUYHVLQ)LJVKRZWKHSRZHUUDWLQJIRU JURXSVRIUHVLVWRUVZLWKYDULRXVVSDFLQJVEHWZHHQWKHFORVHVW SRLQWVRIWKHUHVLVWRUVDVVXPLQJRSHUDWLRQDWPD[LPXPSHU PLVVLEOHKRWVSRWWHPSHUDWXUH,IUHVLVWRUVDUHWREHRSHUDWHGDW

ORZHUKRWVSRWWHPSHUDWXUHVWKHDPRXQWRIGHUDWLQJIRUJURXS LQJFDQEHUHGXFHG Derating for Altitude 7KHFXUYHLQ)LJVKRZVWKHSURSRUWLRQDOZDWWVIRUYDULRXV DOWLWXGHVDVVXPLQJVWDQGDUGDWPRVSKHULFFRQGLWLRQV EN VI ME L F CTO SE FF ECT O THE POWE RA TI G O COMPO TS 100 Percent of Single Unit W attage Rating Number of Resistors in Group 60 20 246 135 80 40 2" (50.8 mm) space 89 10

11 12 1" (25.4 mm) space 0.5" (12.7 mm) space Fig.6: erating of Resistors to Allow for rouping Fig. 4: erating of Resistors for igh Ambient emperatures. Fig.5: xample of ffect of ize of nclosure on emperature Rise of An nclosed Resistor. 100 300 Percent Rated Load 100 02 57 50 200 Te mperature Rise 540 500 400 300 200 100 Resistor in Small Bo Resistor in Large Bo Box Te mp., Small Box Te mp., Large Resistor in Free Ai Resistor: 100 watt, 0.75 x 6.5" (19.05 x 165.10 mm) In unpainted 0.032" (0.813 mm) thick upainted sheet steel box, no vents Small box: 3.375 x 3.375 x 8" (85.725 x 85.725 x

203.20 mm) Large box: 5.813 x 5.813 x 12.75" (147.65 x 147.65 x 323.85 mm) Fig. 7: erating for Altitude 70 100 Percent Rated W atts Altitude in Thousands of Feet 60 20 02 04 06 10 30 50 80 40 5000 ft. 100 90 80 350 100 Percent Rated W atts Ambient Te mperature, 60 20 100 200 300 50 150 250 80 40 U.L.-NEMA Std. for Resistors Ind. & Comm. Std. Mil-R-26: Char . V. EIA: Char . E, H & Mil-R-26: Char . EIA: Char . 25 40 275 340 Resistor Selection Application Notes
Page 5

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WKHUDWLQJVYDU\JUHDWO\ZLWKWKHUHVLVWDQFHRUPRUHVSHFLILFDOO\ ZLWKWKHDFWXDOZHLJKWDQGVSHFLILFKHDWRIWKHUHVLVWDQFHDOOR\ XVHG&DOFXODWLRQLVEDVHGRQWKHDVVXPSWLRQWKDWDOORIWKH KHDWJHQHUDWHGLQWKHSXOVHJRHVWRUDLVHWKHWHPSHUDWXUHRI WKHUHVLVWDQFHZLUH Fig. 8: ercent of

ontinuous uty Rating for Resistors for ypical N EM A uty ycles. Fig. 9: ime Required for ypical Resistors to Reach Rated perating emperatures at arious att oads. 1000 Percent of Continuous-duty W attage Rating NEM A Duty Cycles 400 600 100 10 15 15 51 51 1200 800 Powr-rib (low resistance) 02 04 10 30 50 15 35 52 54 200 1400 100 150 175 200 225 250 275 300 325 350 125 375 70 45 15 75 75 30 0.125 x 8.5" Corrib (28.575 x 215.90 mm Powr-rib (high resistance) seconds on: seconds of f: Percent of Continuous-duty Current Rating Duty Cycle in Percent 700 Percent of Continuous-duty W attage Rating On

Ti me in Seconds to Reach Rated Te mperature 400 500 100 10 30 200 52 100 800 600 200 watt vitreous enamel 1500 watt Corrib 0.125" (3.175 mm), ribbon Low-resistance Powr-rib, edgewound 300 watt Corrib 0.125" (3.175 mm), ribbon 10 & 50 watt vitreous enamel High-resistance Powr-rib, roundwire 0.1 0.5 0.3 21 0.4 0.2 15 200 1000 On Ti me in Minutes to Reach Rated Te mperature 20 30 50 300 500 1000 2000 300 000 Resistor Selection Application Notes
Page 6

2+0,7(,QWO)D[ZZZRKPLWHFRPLQIR#RKPLWHFRP 200 ULSE PE RA TIO OOLI G IMITED EMPE RA TU ES Fig. 14: ercent of Free Air Rating for ypical Resistor ooled by Forced Air

irculation. Fig. 10: 10 ercent of ontinuous uty Rating for ulse peration of small to edium ize itreous nameled Resistors. Fig. 11: ercent of ontinuous uty Rating for ulse peration of arge itreous nameled Resistors. Fig.12: ercent of ontinuous uty Rating for ulse peration of CO RR , orrugated Ribbon Resistors. Fig. 13: ercent of ontinuous uty Rating for ulse peration of owr-Rib , Bare Resistors Cooling Air 5HVLVWRUVFDQEHRSHUDWHGDWKLJKHUWKDQUDWHGZDWWDJHZKHQ

FRROHGE\IRUFHGFLUFXODWLRQRIDLU$W\SLFDOFXUYHLVLOOXVWUDWHG LQ)LJ7KHFXUYHWHQGVWROHYHORIIDWKLJKHUYHORFLWLHVDV H[FHVVLYHKRWVSRWVGHYHORSZKHUHWKHDLUIORZGRHVQRWUHDFK DOOSDUWVXQLIRUPO\ Limited Temperature Rise

:KHQLWLVGHVLUHGWRRSHUDWHDUHVLVWRUDWOHVVWKDQPD[LPXP WHPSHUDWXUHULVHWKHSHUFHQWZDWWVIRUDJLYHQULVHFDQEH UHDGIURP7HPSHUDWXUH5LVHYV5HVLVWRU/RDG)LJJUDSKRQ SDJH 10 On T ime in Seconds Off Ti me in Seconds 11 24 30 100 20 40 50 70 300 1K 200 400 500 700 3K 10K 2K 4K 5K 7K 100 40 50 70 20 30 100 40 50 70 20 30 125%

Small V itreous Enamel Resistors 10 watt 50 watt 150% 200% 500% 1000% 10 On Ti me in Seconds Off Ti me in Seconds 11 24 30 100 20 40 50 70 300 1K 200 400 500 700 3K 10K 2K 4K 5K 7K 100 40 50 70 20 30 100 40 50 70 20 30 125% Large V itreous Enamel Resistors 160 watt shown 150% 200% 500% 1000% 500 400 Percent Rated W atts Air V elocity , ft./min. 300 200 100 1000 1500 350 250 150 10 On Ti me in Seconds Off Ti me in Seconds 11 24 30 100 20 40 50 70 300 1K 200 400 500 700 3K 10K 2K 4K 5K 7K 100 40 50 70 20 30 100 40 50 70 20 30 Corrib Resistors 300 watt 1500 watt 200% 500% 1000% round wire

edgewound 10 On Ti me in Seconds Off Ti me in Seconds 11 24 30 100 20 40 50 70 300 1K 200 400 500 700 3K 10K 2K 4K 5K 7K 100 40 50 70 20 30 100 40 50 70 20 30 Powr-ribs round wire edgewound 200% 500% 1000% 300% 800% 200% 500% 1000% 300% 800% Resistor Selection Application Notes
Page 7

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)RUHDFK&RQGLWLRQORFDWHWKHUHOHYDQWYDOXHRQWKHVFDOHVEHORZ DQGUHFRUGWKHFRUUHVSRQGLQJ)DFWRU) WR) 1RWH7KH6WDQGDUG )UHH$LU&RQGLWLRQ)DFWRULVDOZD\V Four resistors, each dissipating 115 watts, are to be mounted in a group. Spacing is to be 2 surface to sur face. Ambient to be 50C (122F). Enclosure to be total. Other factors standard. Determine Watt

Size required. Operation (1) 2Q$PELHQW7HPSHUDWXUHVFDOHORFDWH&1RWHDQG UHFRUG)  DVVKRZQ/RFDWHDQGUHFRUGWKHRWKHUIDFWRUV Operation (2) 0XOWLSO\WKHIDFWRUVWRJHWKHU Operation (3) :DWWV[

:DWWV)UHH$LU:DWW6L]H5DWLQJ UHTXLUHGIRUHDFKUHVLVWRU F F 50 100% 4@2 Standard Conditions 1.1 x 2.0 x 1.2 x 1 x 1 x 1 1 watts to be dissipated factor factor factor factor factor factor factor Te mperature at installation includes room temperature plus temperature rise due to adjacent heat sources. Factors apply approximately for average sheet metal boxes of dimensions such that watts per sq. in. of surface are in the range of 0.2 to 0.4. Factors apply to uniformly spaced banks of parallel

resistors with spacing as shown. Factors apply to altitudes show . No derating is required for altitudes to 5000 ft. above sea level. Percent load for pulse operation must first be determined from graphs and data on page xx Factors are approximations only . Ef fectiveness of cooling varies with installation. Low temperatures may be desired because of adjacent apparatus, increased stability or maximum reliability Record th watts to be dissipated as set by your circui conditions. Standard free ai conditions CF % F no. ft. % F fpm CF 300 6.6 3.2 2.7 2.2 1.9 1.6 1.4 1.3 1.2 1.1 1.0 4.1 5.0 200 100

50 25 100 2.0 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 1.9 90 80 70 None 60 50 40 30 20 10 1.4 1.6 1.5 1.4 1.5 1.3 1.4 1.3 1.2 1.0 1.3 12 12 12 1.3 1.4 1.2 1.1 2" space 1" space 0.5" space std. brackets 100 1.5 1.5 1.4 1.3 1.2 1.1 1.0 90 80 70 60 50 40 30 20 10 1.0 1000 0.10 0.50 900 800 700 600 500 400 300 200 100 1.0 0.1 0.12 0.13 0.14 0.15 0.16 0.17 0.18 0.19 0.20 0.25 0.30 0.35 0.40 0.60 0.75 thousands of feet percent load 1500 0.27 900 800 700 600 500 400 300 200 Still 1.0 0.28 0.29 0.30 0.32 0.35 0.40 0.50 0.60 0.70 0.80 0.90 100 1400 1300 1200 100 1000 air velocity: feet per minute 40 13.0

300 200 1.0 10.0 8.0 6.0 4.0 3.0 1.75 1.3 1.2 1.1 100 50 7.0 5.0 2.5 2.0 1.5 1.4 Ambient Te perature Enclosure Grouping Altitude Pulse Operation Cooling Ai Limited Te mp. Rise Application Conditions atts EXAMPL Resistor Selection Application Notes 2. 0XOWLSO\WKH)DFWRUVWRJHWKHU 3. 0XOWLSO\WKH:DWWVE\WKHSURGXFWREWDLQHGIURPDERYH
Page 8

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Page 9

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Page 10

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PXFKFXUUHQWZLOOIORZWKURXJKD FRPSRQHQW5HVLVWRUVDUHXVHGWR FRQWUROYROWDJHDQGFXUUHQWOHYHOV$ YHU\KLJKUHVLVWDQFHDOORZVDVPDOO DPRXQWRIFXUUHQWWRIORZ$YHU\ORZ UHVLVWDQFHDOORZVDODUJHDPRXQWRI FXUUHQWWRIORZ5HVLVWDQFHLVPHD VXUHGLQRKPV

3RZHULVWKHDPRXQWRIFXUUHQW WLPHVWKHYROWDJHOHYHODWDJLYHQ SRLQWPHDVXUHGLQZDWWDJHRUZDWWV 118 16 169 18 18 191 196 7RO E96 Values 3OXV DQG 7RO E24 Values 3OXV DQG 7RO E12 Values 3OXV DQG 7RO E6 Values 3OXV DQG 619 68 68 68 681 698 866 91

7RO E96 Values 3OXV DQG 7RO E24 Values 3OXV DQG 7RO E12 Values 3OXV DQG 7RO E6 Values 3OXV DQG 7RO E96 Values 3OXV DQG 7RO E24 Values 3OXV DQG 7RO E12 Values 3OXV DQG 7RO E6 Values 3OXV

DQG Resistance Values referred tandard Resistance alues 7KHUHVLVWDQFHYDOXHVOLVWHGEHORZDQGWKHLUGHFLPDOPXOWLSOHV KDYHEHHQGHVLJQDWHGDVVWDQGDUGE\WKH,QWHUQDWLRQDO(OHF WURWHFKQLFDO&RPPLVVLRQ,(&7KLVOLVWLQJHQVXUHVWKDWHYHU\ SRVVLEOHUHVLVWDQFHYDOXHZLWKLQLWVUHVSHFWLYHWROHUDQFHUDQJH

LVUHSUHVHQWHG7KHRPLVVLRQRIDUHVLVWDQFHYDOXHGRHVQRW QHFHVVDULO\PHDQWKDW2KPLWHFDQQRWPDQXIDFWXUHWKHGHVLUHG YDOXH 3OHDVHFRQWDFW2KPLWHDWRUVDOHV#RKPLWH FRPIRUUHVLVWDQFHYDOXHVQRWVKRZQLQWKLVWDEOH
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2+0,7(,QWO)D[ZZZRKPLWHFRPLQIR#RKPLWHFRP 205 Resistor Terminology Adjustable Resistor: $UHVLVWRUVRFRQVWUXFWHG

WKDWLWVUHVLVWDQFHFDQEHUHDGLO\FKDQJHG Alternating Current: $SHULRGLFFXUUHQWWKH DYHUDJHYDOXHRIZKLFKRYHUDSHULRGLV]HUR 7KHHTXDWLRQIRUDOWHUQDWLQJFXUUHQWLVWKHVDPH DVWKDWIRUDSHULRGLFFXUUHQWH[FHSWWKDW, 2 Ambient Temperature: 7KHWHPSHUDWXUHRI WKHVXUURXQGLQJFRLOLQJPHGLXPVXFKDVJDV

RUOLTXLGZKLFKFRPHVLQWRFRQWDFWZLWKKHDWHG SDUWVRIWKHDSSDUDWXV Ampere: 7KHXQLWRIFRQVWDQWFXUUHQWZKLFK PDLQWDLQHGLQWZRSDUDOOHOUHFWLOLQHDUFRQGXF WRUVRILQILQLWHOHQJWKVHSDUDWHGE\DGLVWDQFHRI RQHPHWHUSURGXFHVEHWZHHQWKHVHFRQGXFWRUV DIRUFHHTXDOWR[

PNVPHWHUNLORJUDP VHFRQGXQLWVRIIRUFHSHUPHWHURIOHQJWK Armature Resistor: $UHVLVWRUFRQQHFWHGLQ VHULHVZLWKWKHDUPDWXUHRIDPRWRUHLWKHUWR OLPLWWKHLQUXVKFXUUHQWRQVWDUWLQJWKHJUDGXDO VKRUWFLUFXLWLQJRIZKLFKEULQJVWKHPRWRUWR

QRUPDOVSHHGRUWRUHJXODWHWKHVSHHGE\ DUPDWXUHYROWDJHFRQWURO Axiohm : &HQWRKP &RDWHGD[LDOWHUPLQDO ZLUHZRXQGUHVLVWRU Bracket Terminal Resistor: $UHVLVWRU HTXLSSHGZLWKVORWWHGPHWDOHQGMEUDFNHWVWKDW VHUYHDVDPHDQVRIPRXQWLQJDQGFRQQHFWLQJ WRWKHUHVLVWRU Capacitance: 7KDWSURSHUW\RIDV\VWHPRI

FRQGXFWRUVDQGGLHOHFWULFVZKLFKSHUPLWVWKH VWRUDJHRIHOHFWULFLW\ZKHQSRWHQWLDOGLIIHU HQFHVH[LVWEHWZHHQWKHFRQGXFWRUV,WVYDOXHLV H[SUHVVHGDVWKHUDWLRRIDTXDQWLW\RIHOHFWULFLW\ WRDSRWHQWLDOGLIIHUHQFH$FDSDFLWDQFHYDOXHLV DOZD\VSRVLWLYH Capacitor: $GHYLFHWKHSULPDU\SXUSRVHRI

ZKLFKLVWRLQWURGXFHFDSDFLWDQFHLQWRDQHOHF WULFFLUFXLW&DSDFLWRUVDUHXVXDOO\FODVVLILHG DFFRUGLQJWRWKHLUGLHOHFWULFVDVDLUFDSDFLWRUV PLFDFDSDFLWRUVSDSHUFDSDFLWRUVHWF Clearance: 7KHVKRUWHVWGLVWDQFHWKURXJK VSDFHEHWZHHQWZROLYHSDUWVEHWZHHQOLYH

SDUWVDQGVXSSRUWVRURWKHUREMHFWVRUEHWZHHQ DQ\OLYHSDUWDQGJURXQGHGSDUW Conduction: 7KHWUDQVPLVVLRQRIKHDWRUHOHF WULFLW\WKURXJKRUE\PHDQVRIDFRQGXFWRU Conductor: $ERG\VRFRQVWUXFWHGIURPFRQ GXFWLQJPDWHULDOWKDWLWPD\EHXVHGDVDFDUULHU RIHOHFWULFFXUUHQW Continuous Duty:

$UHTXLUHPHQWRIVHUYLFH WKDWGHPDQGVRSHUDWLRQDWDVXEVWDQWLDOO\FRQ VWDQWORDGIRUXQLQGHILQLWHO\ORQJWLPH Continuous-Duty Resistor: $UHVLVWRUWKDWLV FDSDEOHRIFDUU\LQJFRQWLQXRXVO\WKHFXUUHQW IRUZKLFKLWLVGHVLJQHGZLWKRXWH[FHHGLQJWKH VSHFLILHGWHPSHUDWXUHULVH Continuous Rating: &RQWLQXRXVUDWLQJLVWKH

UDWLQJWKDWGHILQHVWKHORDGZKLFKFDQEHFDU ULHGIRUDQLQGHILQLWHO\ORQJWLPH Convection: &RQYHFWLRQLVWKHPRWLRQUHVXOWLQJ LQDIOXLGRZLQJWRGLIIHUHQFHVRIGHQVLW\DQGWKH DFWLRQRIJUDYLW\ Corrib : $WXEXODUUHVLVWRUFRQVLVWLQJRIDQ DOOR\UHVLVWDQFHULEERQFULPSHGDQGHGJH

ZRXQGRQDFHUDPLFFRUHWKHULEERQEHLQJ VHFXUHO\DQGSHUPDQHQWO\IDVWHQHGWRWKHFRUH E\YLWUHRXVHQDPHORUFHPHQW Creepage Distance: 7KHVKRUWHVWGLVWDQFH EHWZHHQFRQGXFWRUVRIRSSRVLWHSRODULW\RU EHWZHHQDOLYHSDUWDQGJURXQGDVPHDVXUHG RYHUWKHVXUIDFHRIWKHVXSSRUWLQJPDWHULDO Current-limiting Resistor:

$UHVLVWRULQVHUWHG LQWRDQHOHFWULFFLUFXLWWROLPLWWKHIORZRIFXUUHQW WRVRPHSUHGHWHUPLQHGYDOXH1RWH$FXUUHQW OLPLWLQJUHVLVWRUXVXDOO\LQVHULHVZLWKDIXVHRU FLUFXLWEUHDNHUPD\EHHPSOR\HGWROLPLWWKH IORZRIFLUFXLWRUV\VWHPHQHUJ\DWWKHWLPHRID

IDXOWRUVKRUWFLUFXLW Dielectric Strength: 7KHGLHOHFWULFVWUHQJWKRI DQLQVXODWLQJPDWHULDOLVWKHPD[LPXPSRWHQWLDO JUDGLHQWWKDWWKHPDWHULDOFDQZLWKVWDQGZLWKRXW UXSWXUH,WLVXVXDOO\VSHFLILHGLQYROWVSHUXQLW WKLFNQHVV Dielectric Test: $WHVWZKLFKFRQVLVWVRIWKH

DSSOLFDWLRQRIDYROWDJHKLJKHUWKDQWKHUDWHG YROWDJHIRUDVSHFLILHGWLPHIRUWKHSXUSRVHRI GHWHUPLQLQJWKHDGHTXDF\DJDLQVWEUHDNGRZQ RILQVXODWLQJPDWHULDOVDQGVSDFLQJVXQGHUQRU PDOFRQGLWLRQV Direct Current: $XQLGLUHFWLRQDOFXUUHQWLQ ZKLFKWKHFKDQJHVLQYDOXHDUHHLWKHU]HURRU

VRVPDOOWKDWWKH\PD\EHQHJOHFWHG$JLYHQ FXUUHQWZRXOGEHFRQVLGHUHGDGLUHFWFXUUHQWLQ VRPHDSSOLFDWLRQVEXWZRXOGQRWQHFHVVDULO\ EHVRFRQVLGHUHGLQRWKHUDSSOLFDWLRQV Dividohm : $UHVLVWRUZLWKDEDUHVLGHDQG FODPSIRUDGMXVWPHQW Edgeohm $KLJKFXUUHQWUHVLVWRUPDGHRIDQ

DOOR\UHVLVWDQFHULEERQZRXQGRQHGJHIRUP LQJDQRYDOVKDSHGFRLOVXSSRUWHGE\JURRYHG LQVXODWRUVZKLFKVSDFHDGMDFHQWWXUQVDQG LQVXODWHWKHPIURPWKHVXSSRUWEDUV6XSSRUW EDUVDUHVHFXUHGWRVWHHOHQGSLHFHVIRUPLQJ DVWXUG\UHVLVWRUVXLWDEOHIRUFRQWLQXRXVDQG LQWHUPLWWHQWGXW\DSSOLFDWLRQV EIA:

(OHFWURQLF,QGXVWULHV$OOLDQFH Electromotive Force: 7KHHOHFWURPRWLYHIRUFH LVWKHDJHQF\FDXVLQJWKHIORZRIFXUUHQWLQ DFLUFXLW,WLVWKHHOHFWULFDOSUHVVXUHRUGURS PHDVXUHGLQYROWV Farad: 7KHXQLWRIFDSDFLWDQFHRIDQHOHFWULF FRQGHQVHULQZKLFKDFKDUJHRIRQHFRXORPE

SURGXFHVDGLIIHUHQFHRISRWHQWLDORIRQHYROW EHWZHHQWKHSROHVRIWKHFDSDFLWRU Ferrule Resistor: $UHVLVWRUVXSSOLHGZLWKIHU UXOHWHUPLQDOVIRUPRXQWLQJLQVWDQGDUGIXVH FOLSV Field Discharge Switch: $VZLWFKXVXDOO\RI WKHNQLIHEODGHW\SHKDYLQJDX[LOLDU\FRQWDFWV IRUFRQQHFWLQJWKHILHOGRIDJHQHUDWRURUPRWRU

DFURVVDUHVLVWRUILHOGGLVFKDUJHDWWKHLQVWDQW SUHFHGLQJWKHRSHQLQJRIWKHVZLWFK Fixed Resistor: $UHVLVWRUGHVLJQHGWRLQWUR GXFHRQO\RQHVHWDPRXQWRIUHVLVWDQFHLQWRDQ HOHFWULFDOFLUFXLW Henry: 7KHXQLWRILQGXFWDQFHRIDFORVHGFLU FXLWLQZKLFKDQHOHFWURPRWLYHIRUFHRIRQHYROW

LVSURGXFHGZKHQWKHHOHFWULFFXUUHQWWUDYHUVLQJ WKHFLUFXLWYDULHVXQLIRUPO\DWWKHUDWHRIRQH DPSHUHSHUVHFRQG Hot Spot: 7KHSRLQWRUORFDWLRQRIPD[LPXP WHPSHUDWXUHRQWKHH[WHUQDOVXUIDFHRIDUHVLV WRU Inductance: 7KHVFDODUSURSHUW\RIDQHOHF WULFFLUFXLWRURIWZRQHLJKERULQJFLUFXLWVZKLFK

GHWHUPLQHVWKHHOHFWURPRWLYHIRUFHLQGXFHGLQ RQHRIWKHFLUFXLWVE\DFKDQJHRIFXUUHQWLQ HLWKHURIWKHP Impedance: 7KHDSSDUHQWUHVLVWDQFHRIDQ $&FLUFXLWEHLQJWKHFRPELQDWLRQRIERWKWKH UHVLVWDQFHDQGUHDFWDQFH,WLVHTXDOWRWKHUDWLR

RIWKHYDOXHRIWKH(0)EHWZHHQWKHWHUPLQDOV WRWKHFXUUHQWWKHUHEHLQJQRVRXUFHRISRZHU LQWKHSRUWLRQXQGHUFRQVLGHUDWLRQ7KHXQLW RILPSHGDQFHLVWKHRKPDQGLVUHSUHVHQWHG E\= Intermittent Duty: $UHTXLUHPHQWRIVHUYLFH WKDWGHPDQGVRSHUDWLRQIRUDOWHUQDWHLQWHUYDOV

RIORDGDQGQRORDGRUORDGDQGUHVWRU ORDGQRORDGDQGUHVWVXFKDOWHUQDWHLQWHU YDOVEHLQJGHILQLWHO\VSHFLILHG Intermittent-Duty Resistor: $UHVLVWRUFDSDEOH RIFDUU\LQJIRUDVKRUWSHULRGRIWLPHWKHKLJK

RYHUORDGFXUUHQWIRUZKLFKLWLVGHVLJQHGZLWKRXW H[FHHGLQJWKHVSHFLILHGWHPSHUDWXUHULVH Machine-Duty Resistor: $UHVLVWRUIRUXVHLQ WKHDUPDWXUHRUURWRUFLUFXLWRIDPRWRULQZKLFK WKHDUPDWXUHFXUUHQWLVDOPRVWFRQVWDQW Mega Ohm: $XQLWRIUHVLVWDQFHHTXDOWRRQH PLOOLRQRKPV MIL Resistor:

$UHVLVWRUEXLOWLQDFFRUGDQFH ZLWK-RLQW$UP\1DY\VSHFLILFDWLRQV Multi-Section Resistor: $UHVLVWRUKDYLQJWZR RUPRUHHOHFWULFDOO\LQGHSHQGHQWVHFWLRQV NEC: 7KH1DWLRQDO(OHFWULFDO&RGHLVWKHVWDQ GDUGRIWKH1DWLRQDO%RDUGRI)LUH8QGHUZULWHUV IRUHOHFWULFZLULQJDQGDSSDUDWXVDVUHFRP

PHQGHGE\WKH1DWLRQDO)LUH3URWHFWLRQ $VVRFLDWLRQDQGDSSURYHGE\WKH$PHULFDQ 6WDQGDUGV$VVRFLDWLRQ NEDA: 1DWLRQDO(OHFWURQLF'LVWULEXWRUV $VVRFLDWLRQ NEMA: 7KH1DWLRQDO(OHFWULFDO0DQXIDFWXUHUV $VVRFLDWLRQDQRQSURILWWUDGHDVVRFLDWLRQ VXSSRUWHGE\WKHPDQXIDFWXUHUVRIHOHFWULFDO DSSDUDWXVDQGVXSSOLHV1(0$LVHQJDJHG

LQVWDQGDUGL]DWLRQWRIDFLOLWDWHXQGHUVWDQGLQJ EHWZHHQWKHPDQXIDFWXUHUVDQGXVHUVRIHOHF WULFDOSURGXFWV Nominal Diameter: $VDSSOLHGWRWXEXODUUHVLV WRUVWKLVLVWKHGLDPHWHURIWKHFHUDPLFWXEH H[SUHVVHGLQLQFKHVDQGRUIUDFWLRQVWKHUHRI Nominal Length: $VDSSOLHGWRWXEXODUUHVLV

WRUVWKLVLVWKHOHQJWKRIWKHUHVLVWRUEDVH RUFRUHH[SUHVVHGLQLQFKHVDQGRUIUDFWLRQV WKHUHRI Non-Inductive Resistor: $QRQLQGXFWLYH SRZHUUHVLVWRULVRQHLQZKLFKWKHLQGXFWDQFH DQGGLVWULEXWHGFDSDFLWDQFHDUHUHGXFHGWRDQ DEVROXWHPLQLPXP Ohm: $XQLWRIUHVLVWDQFHGHILQHGDVWKHUHVLV

WDQFHDW&RIDFROXPQRIPHUFXU\RIXQLIRUP FURVVVHFWLRQKDYLQJDOHQJWKRIFHQWLPH WHUVDQGDPDVVRIJUDPV Ohmmeter: $QLQVWUXPHQWIRUPHDVXULQJHOHF WULFUHVLVWDQFHWKDWLVSURYLGHGZLWKDVFDOH JUDGXDWHGLQRKPV Periodic Duty:

$W\SHRILQWHUPLWWHQWGXW\LQ ZKLFKWKHORDGFRQGLWLRQVDUHUHJXODUO\UHFXU UHQW Periodic Rating: 7KHUDWLQJZKLFKGHILQHV WKHORDGZKLFKFDQEHFDUULHGIRUWKHDOWHUQDWH SHULRGVRIORDGDQGUHVWVSHFLILHGLQWKHUDWLQJ WKHDSSDUDWXVVWDUWLQJFROGDQGIRUWKHWRWDOWLPH

VSHFLILHGLQWKHUDWLQJZLWKRXWFDXVLQJDQ\RI WKHVSHFLILHGOLPLWDWLRQVWREHH[FHHGHG Power: 7KHWLPHUDWHRIWUDQVIHUULQJRUWUDQV IRUPLQJHQHUJ\WKHUDWHRIGRLQJZRUNRU H[SHQGLQJHQHUJ\ Power Resistor: $UHVLVWRUFDSDEOHRIGLVVLSDW LQJZDWWVRUPRUH Rating: $GHVLJQDWHGOLPLWRIRSHUDWLQJFKDU

DFWHULVWLFVRIDPDFKLQHDSSDUDWXVRUGHYLFH EDVHGRQGHILQLWHFRQGLWLRQV
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2+0,7(,QWO)D[ZZZRKPLWHFRPLQIR#RKPLWHFRP 206 Resistor Terminology RESISTANCE VALUES Abbreviations and Part Numbering Structure Note 1: Such operating characteristics as

load, voltage, frequency, etc., may be given in the rating. Note 2: The rating of control apparatus in gener al is expressed in volts, amperes, horsepower or kilowatts as may be appropriate, except that resistors are rated in ohms, amperes and class of service.* Reactor: $GHYLFHXVHGIRULQWURGXFLQJUHDF WDQFHLQWRDFLUFXLWIRUSXUSRVHVVXFKDVPRWRU VWDUWLQJSDUDOOHOLQJWUDQVIRUPHUVDQGFRQWURORI FXUUHQW Rectifier:

$GHYLFHZKLFKFRQYHUWVDOWHUQDWLQJ FXUUHQWWRXQLGLUHFWLRQDOFXUUHQWE\YLUWXHRID FKDUDFWHULVWLFSHUPLWWLQJDSSUHFLDEOHIORZRI FXUUHQWLQRQO\RQHGLUHFWLRQ Resistance: 7KHVFDODUSURSHUW\RIDQHOHFWULF FLUFXLWRURIDQ\ERG\ZKLFKPD\EHXVHGDV

SDUWRIDQHOHFWULFFLUFXLWZKLFKGHWHUPLQHVIRUD JLYHQFXUUHQWWKHUDWHDWZKLFKHOHFWULFHQHUJ\ LVFRQYHUWHGLQWRKHDWRUUDGLDQWHQHUJ\DQG ZKLFKKDVDYDOXHVXFKWKDWWKHSURGXFWRIWKH UHVLVWDQFHDQGWKHVTXDUHRIWKHFXUUHQWJLYHV

WKHUDWHRIFRQYHUVLRQRIHQHUJ\,QWKHJHQHUDO FDVHUHVLVWDQFHLVDIXQFWLRQRIWKHFXUUHQWEXW WKHWHUPLVPRVWFRPPRQO\XVHGLQFRQQHFWLRQ ZLWKFLUFXLWVZKHUHWKHUHVLVWDQFHLVLQGHSHQ GHQWRIWKHFXUUHQW Resistance Tolerance: 7KHUHVLVWDQFHWRO

HUDQFHRIDSRZHUUHVLVWRULVWKHH[WHQWWR ZKLFKLWVUHVLVWDQFHPD\EHSHUPLWWHGWRGHYL DWHDERYHRUEHORZWKHVSHFLILHGUHVLVWDQFH 5HVLVWDQFHWROHUDQFHLVXVXDOO\H[SUHVVHGLQ SHUFHQW Resistance Method of Temperature Determination: 7KLVPHWKRGFRQVLVWVLQWKH GHWHUPLQDWLRQRIWHPSHUDWXUHE\FRPSDULVRQRI

WKHUHVLVWDQFHRIWKHZLQGLQJDWWKHWHPSHUDWXUH WREHGHWHUPLQHGZLWKWKHUHVLVWDQFHDWDNQRZQ WHPSHUDWXUH Resistive Conductor: $UHVLVWLYHFRQGXFWRULV DFRQGXFWRUXVHGSULPDULO\EHFDXVHLWSRVVHVV HVWKHSURSHUW\RIKLJKHOHFWULFUHVLVWDQFH Resistivity: 7KHUHVLVWLYLW\RIDPDWHULDOLVWKH

UHVLVWDQFHRIDVDPSOHRIWKHPDWHULDOKDYLQJ VSHFLILHGGLPHQVLRQV Resistor: $GHYLFHWKHSULPDU\SXUSRVHRI ZKLFKLVWRLQWURGXFHUHVLVWDQFHLQWRDQHOHFWULF FLUFXLW Resistor Core: 7KHUHVLVWRUFRUHRUEDVHRI DSRZHUUHVLVWRULVWKHLQVXODWLQJVXSSRUWRQ ZKLFKWKHUHVLVWLYHFRQGXFWRULVZRXQG Rheostat:

$QDGMXVWDEOHUHVLVWRUVRFRQVWUXFW HGWKDWLWVUHVLVWDQFHPD\EHFKDQJHGZLWKRXW RSHQLQJWKHFLUFXLWLQZKLFKLWPD\EHFRQ QHFWHG Screw-Base Resistor: $SRZHUW\SHUHVLVWRU HTXLSSHGZLWK(GLVRQW\SHVFUHZEDVHWHUPL QDOVIRUTXLFNLQWHUFKDQJHDELOLW\ Short-Time Rating: 7KHUDWLQJWKDWGHILQHVWKH

ORDGZKLFKFDQEHFDUULHGIRUDVKRUWDQGGHIL QLWHO\VSHFLILHGWLPHWKHPDFKLQHDSSDUDWXVRU GHYLFHEHLQJDWDSSUR[LPDWHO\URRPWHPSHUD WXUHDWWKHWLPHWKHORDGLVDSSOLHG Silicone: $VLOLFRQHFRDWLQJPHHWLQJ0,/5 XVHGRQSRZHUW\SHZLUHZRXQGUHVLVWRUV Slim Mox

$IODWVW\OHUHVLVWRU2KPLWHPDQXIDF WXUHV7KH\DUHDYDLODEOHLQDYDULHW\RIVL]HV DQGYDOXHV Single-Wound Resistor: $UHVLVWRUWKDWKDV RQO\RQHOD\HURIUHVLVWDQFHZLUHRUULEERQ ZRXQGDURXQGWKHLQVXODWLQJEDVHRUFRUH Stackohm : $UHVLVWRUFRQVLVWLQJRIDKROORZ

FHUDPLFFRUHRYDOLQVKDSHDERXWZKLFKUHVLV WDQFHZLUHLVZRXQGDQGFRPSOHWHO\HPEHGGHG LQDQLQVXODWLQJDQGKHDWFRQGXFWLQJFRDWLQJ Still Air: 6WLOODLULVFRQVLGHUHGDLUKDYLQJQR FLUFXODWLRQH[FHSWWKDWFUHDWHGE\WKHKHDWRI WKHUHVLVWRUZKLFKLVEHLQJRSHUDWHG Tapped Resistor:

$UHVLVWRUZLWKWZRRUPRUH VWHSV Temperature Coefficient of Resistance: A PHDVXUHRIWKHLQFUHDVHRUGHFUHDVHLQUHVLV WDQFHRIDUHVLVWLYHFRQGXFWRUGXHWRFKDQJHLQ WHPSHUDWXUHLQSDUWVSHUPLOOLRQSSP 5  5 >5 7 @ :KHUH

5HVLVWDQFHRIFRQGXFWRUDWWHPSHUDWXUH 5HVLVWDQFHRIFRQGXFWRUDWUHIHUHQFH WHPSHUDWXUH7 7HPSHUDWXUHFRHIILFLHQWRIUHVLVWDQFHDW UHIHUHQFHWHPSHUDWXUH7 Temperature Rise: 7HPSHUDWXUHULVHLVWKHGLI IHUHQFHLQWHPSHUDWXUHEHWZHHQWKHLQLWLDODQG ILQDOWHPSHUDWXUHRIDUHVLVWRU7HPSHUDWXUHULVH

LVH[SUHVVHGLQGHJUHHV&RU)XVXDOO\UHIHUUHG WRDQDPELHQWWHPSHUDWXUH7HPSHUDWXUHULVH HTXDOVWKHKRWVSRWWHPSHUDWXUHPLQXVWKH DPELHQWWHPSHUDWXUH Thermal Shock: 7KHUPDOVKRFNFRQVLVWVRID VXGGHQPDUNHGFKDQJHLQWKHWHPSHUDWXUHRI WKHPHGLXPLQZKLFKWKHGHYLFHRSHUDWHV Thermocouple:

$GHYLFHIRUFRQYHUWLQJKHDW HQHUJ\LQWRHOHFWULFDOHQHUJ\FRQVLVWLQJRID SDLURIGLVVLPLODUFRQGXFWRUVVRMRLQHGDVWR SURGXFHDWKHUPRHOHFWULFHIIHFW,WLVXVHGZLWK DPLOOLYROWPHWHUWRPHDVXUHWHPSHUDWXUHULVHLQ DSSDUDWXV Thermometer Method of Temperature Determination: 7KLVPHWKRGFRQVLVWVLQWKH

GHWHUPLQDWLRQRIWKHWHPSHUDWXUHE\DPHUFXU\ RUDOFRKROWKHUPRPHWHUE\DUHVLVWDQFHWKHU PRPHWHURUE\DWKHUPRFRXSOHDQ\RIWKHVH LQVWUXPHQWVEHLQJDSSOLHGWRWKHKRWWHVWSDUW RIWKHDSSDUDWXVDFFHVVLEOHWRDPHUFXU\RU DOFRKROWKHUPRPHWHU Tolerance (%) 7KHWROHUDQFHLVWKHDOORZDEOH

GHYLDWLRQIURPWHKQRPLQDOUHVLVWDQFHYDOXH Varying Duty: $UHTXLUHPHQWRIVHUYLFHWKDW GHPDQGVRSHUDWLRQDWORDGVDQGIRULQWHUYDOV RIWLPHERWKRIZKLFKPD\EHVXEMHFWWRZLGH YDULDWLRQ Voltage (V or E): 7KHXQLWRIPHDVXUHLV WKHYROW$XQLWRIHOHFWULFDOSUHVVXUH(0)RU

SRWHQWLDOGLIIHUHQFH2KPLWHVYROWDJHUDWLQJLV WKHYROWDJHWKDWFDQEHDSSOLHGWRWKHUHVLVWRU ZLWKRXWDUFLQJRUGHJUDGLQJWKHUHVLVWRU Voltage Coefficient (VCR) 7KHXQLWRIPHD VXUHLVLQSDUWVSHUPLOOLRQSSP9ROWDJHFRHI ILFLHQWGHILQHVWKHFKDQJHLQWKHYDOXHRIWKH

UHVLVWRUWKDWRFFXUVDVWKHYROWDJHFKDQJHV 7KHUHVLVWRULVPHDVXUHGDWWZRYROWDJHVDQG WKHGHYLDWLRQLVWKHQFDOFXODWHG9&5LVXVXDOO\ VWDWHVDVWKHFKDQJHSHUYROWH[SSPY Watt: $XQLWRIHOHFWULFSRZHU,WLVWKHSRZHU H[SHQGHGZKHQRQHDPSHUHRIGLUHFWFXUUHQW

IORZVWKURXJKDUHVLVWRURIRQHRKP Winding Pitch: 7KHGLVWDQFHIURPDQ\SRLQW RQDWXUQRIDUHVLVWLYHFRQGXFWRUWRWKHFRU UHVSRQGLQJSRLQWRQDQDGMDFHQWWXUQPHDVXUHG SDUDOOHOWRWKHORQJD[LVRIWKHZLQGLQJ $6$6WDQGDUG 1(0$6WDQGDUG 2KPLWHWUDGHQDPH Description Prefix Abbreviation Part

Numbering Structure Numeric V alue Milli Thousandth Centi Hundredth Deci dT enth One Deca, Deka da Te Hecto Hundred Kilo Thousand era TT rillion Giga Billion Mega Million R001 0.001 Milli Ohm R010 0.01 Centi Ohm R100 0.1 Deci Ohm 1R00 11 Ohm 10R0 10 Deca Ohm 1000* 100 Hecto Ohm 1001* 1,000 Kilo Ohm 1002* 10,000 10 Kilo Ohms 1003* 100,000 100 Kilo Ohms 1004* 1,000,000 Mega Ohm 1504* 1,500,000 1.5 Mega Ohms 1005* 10,000,000 10 Mega Ohms 1006* 100,000,000 100 Mega Ohms 1506* 150,000,000 150 Mega Ohms 1007 1,000,000,000 Giga Ohm 1507 1,500,000,000 1.5 Giga Ohms 1008 10,000,000,000 10 Giga Ohms

1009 100,000,000,000 100 Giga Ohms 1509 150,000,000,000 150 Giga Ohms 100A 1,000,000,000,000 1T era Ohm 150A 1,500,000,000,000 1.5 era Ohms 100B 10,000,000,000,000 10 era Ohms *Part Numbering Structure may vary by product line Scientific Notation 1.0 x 10 -3 1.0 x 10 -2 1.0 x 10 -1 1.0 x 10 1.0 x 10 1.0 x 10 1.0 x 10 1.0 x 10 1.0 x 10 1.0 x 10 1.5 x 10 1.0 x 10 1.0 x 10 1.5 x 10 1.0 x 10 1.5 x 10 1.0 x 10 10 1.0 x 10 11 1.5 x 10 11 1.0 x 10 12 1.5 x 10 12 1.0 x 10 13