FORMxSWRTHYPHASCISPELPRGHDOC h PICP69LINP6Z BOXP6Z dOVLP6Z dSWCL@BlackWhiteRedGreenBlueCyanYellowMagentafSalmonwPeachUBrownellowLight GreenwwwGrey DarkOrangeݙVanillalowGrey LightIDXHIDXDSoftSansdTitleepz,IDXDSoftSansdBlank LinefIDXDSoftSansdLetter HeadergIDXDSoftSans dIndex EntryhTOCH TOCDSoftSansdTitlenz%TOCDSoftSans dBlank LineoTOCDSoftSansdZLevel 1pTOCDSoftSans dZLevel 2qTOCDSoftSerif dLevel 3rTOCDSoftSerif dhLevel 4sTOCDSoftSerif dvLevel 5tTOCDSoftSerif d*Level 6uTOCDSoftSerif dLevel 7vTOCDSoftSerif d8Level 8wIDXPSEC1 PTPAG3pA PRN3KBVtils:APPLICATIONS/FinalWriter/FWFonts/SWOLFonts/Serif/WŬWW~WW { dELX.FormulaText{WPASDSoftSansdDocument TitlePASDSoftSansdSection Namepz??PASDSoftSansdTopic Nameq{??PASDSoftSansdSub Topic 1r|??PASDSoftSansdSub Topic 2s}??PASDSoftSans dBodyPASDSoftSans dIndented BodyTOCP!rOUTPBIBPTOIPENDPDSP2PHHFDASoftSans dSoftSans dPNDASoftSans dSHPP6Z dGRMRStrictly.For Business Writing.For Casual Writing.Custom 1.Custom 2.Custom 3.IDXLConductorsTDINFFCOP3W-~W0FDTASoftSans_ItalicW2tW2tW2tWŬUtils:APPLICATIONS/FinalWriter/FWFonts/SWOLFonts/W6W$XW*VW(W^@W*&W+oW*VFDTASymbolbookhUtils:APPLICATIONS/FinalWriter/FWFonts/SWOLFonts/CW=DxW>}pWWFFDTASoftSans_BoldvxWU\WU\WU\WŬUtils:APPLICATIONS/FinalWriter/FWFonts/SWOLFonts/W*W$XW+~W(W^@W+NW+W+~FDTAWorchester Utils:APPLICATIONS/FinalWriter/FWFonts/SWOLFonts/Serif/FDTASoftSansW8W%YW$PWwLWW$oW$WtW_W$PW# W$WtW~GINF 7GINFUtils:GRAPHICS/PPaint/Brushes/FWriter5/Ohmeter.bsh5L25L2 S9BlackFORMILBMBMHD{p",CMAP @@CAMGBODYR@@  n{b8 ?}|~AN` @Zo #={BY)R )N'0.Z խ|-k|ַC)R *RҔ)HZ? 5}kVB)R RRxo{b -}kVy'N`? )҂R@@@@@~@33@` xyg@33@`af??79?3>`??@6@@@3@`@?@ 3@``@s@@  @?q R@j RP @j RL0@k?*` RB@skI \@@@@?x@<@?x@?@?@?@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ !w@ ވ@{w4q@@PCˎ@w]U@\DR@w]UABGR@}խBPD"*R@ձ \ C"*N@@@@FcL@?ZR @?mZ@?Z@?[G> @??@?3`@? ??3`????????s?s?sss`(sl(s{W?sxWk(c(GINF /vTABL~/ddddd (SoftSans dSoftSans dSoftSans dSoftSans dSoftSans dvTCLS jW8DjW8jW8|jW8W8W8 W8W88W8W7 W7 HW7 W7`W7hW7W7W7 W7W7$W7W7<W7W6W60W6W6HW6W7W6<W6<W6=W6=W6>4W6>W6?LW-W-W-W-W-0W-W-W-HW-W-`W-W-xW-W9W9W9,W9W9DW9W9\W9W9tW9W9W9W9W:RW:W:jW9W9 W9W98W9W9PW9W9W9W9W8|\W8|CELLRULEccATTR dCHRSDIVISION RANGECLLECELLRULEQHATTR dCHRSOHMS DIFFERENCECLLECELLRULEH?ATTR dCHRSNo. of DIVISIONSCLLECELLRULEZZATTR dCHRSDIVISIONRULEZZATTR dCHRSVALUECLLECELLRULE ATTR dCHRS 00 - 01 OhmsCLLECELLRULE ATTR dCHRS 1.0 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS0.2 OhmsCLLECELLRULE ATTR dCHRS 01 - 02 OhmsCLLECELLRULE ATTR dCHRS 1.0 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS0.2 OhmsCLLECELLRULE ATTR dCHRS 02 - 05 OhmsCLLECELLRULE ATTR dCHRS 3.0 OhmsCLLECELLRULEATTR dCHRS6CLLECELLRULEATTR dCHRS0.5 OhmsCLLECELLRULE ATTR dCHRS 05 - 10 OhmsCLLECELLRULE ATTR dCHRS 5.0 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS0.5 OhmsCLLECELLRULE ATTR dCHRS 10 - 15 OhmsCLLECELLRULE ATTR dCHRS 5.0 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS1.0 OhmsCLLECELLRULE ATTR dCHRS 15 - 20 OhmsCLLECELLRULE ATTR dCHRS 5.0 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS1.0 OhmsCLLECELLRULE ATTR dCHRS 20 - 30 OhmsCLLECELLRULE ATTR dCHRS 10.0 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS2.0 OhmsCLLECELLRULE ATTR dCHRS 30 - 40 OhmsCLLECELLRULE ATTR dCHRS 10.0 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS2.0 OhmsCLLECELLRULE ATTR dCHRS 40 - 50 OhmsCLLECELLRULE ,ATTR dCHRS ATTR dCHRS 10.0 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS2.0 OhmsCLLECELLRULE ATTR dCHRS 50 - 60 OhmsCLLECELLRULE ,ATTR dCHRS ATTR dCHRS 10.0 OhmsCLLECELLRULEATTR dCHRS2CLLECELLRULEATTR dCHRS5.0 OhmsCLLECELLRULEATTR dCHRS 60 - 70 Ohms....CLLECELLRULE ,ATTR dCHRS ATTR dCHRS 10.0 OhmsCLLECELLRULEATTR dCHRS2CLLECELLRULEATTR dCHRS5.0 OhmsCLLECELLRULEATTR dCHRS 100 - 200 OhmsCLLECELLRULE ,ATTR dCHRS ATTR dCHRS100 OhmsCLLECELLRULEATTR dCHRS5CLLECELLRULEATTR dCHRS20 OhmsCLLECELLRULEATTR dCHRS 200 - 300 OhmsCLLECELLRULE ,ATTR dCHRS ATTR dCHRS100 OhmsCLLECELLRULEATTR dCHRS2CLLECELLRULEATTR dCHRS50 OhmsCLLECELLRULEATTR dCHRS 300 - 400 OhmsCLLECELLRULE ,ATTR dCHRS ATTR dCHRS100 OhmsCLLECELLRULEATTR dCHRS1CLLECELLRULEATTR dCHRS100 OhmsCLLECELLRULEATTR dCHRS 400 - 500 OhmsCLLECELLRULE ,ATTR dCHRS ATTR dCHRS100 OhmsCLLECELLRULEATTR dCHRS1CLLECELLRULEATTR dCHRS100 OhmsCLLECELLRULEATTR dCHRS 500 - 1k OhmsCLLECELLRULE ATTR dCHRS 500 OhmsCLLECELLRULEATTR dCHRS1CLLECELLRULEATTR dCHRS500 OhmsCLLECELLRULE ATTR dCHRS 1k - 2k OhmsCLLECELLRULE ATTR dCHRS 1000 OhmsCLLECELLRULEATTR dCHRS1CLLECELLRULE ATTR dCHRS 1000 OhmsCLLECELLRULEATTR dCHRS 2000 - InfinityCLLECELLRULEATTR dCHRSCLLECELLRULEATTR dCHRSCLLECELLRULEATTR dCHRSCLLEGINF SHD1PW*ϢW*W*VPTMainTBDYRULETATTR dCHRSElectronic Servicing yr.1 pt.1ATTR dCHRS ATTR hdCHRS ATTR hdCHRS ATTR dCHRSLecture: 011.PATTR dCHRS ATTR hdCHRS ATTR hdCHRS ATTR hdCHRS ATTR hdCHRSMonday - 18 - November ATTR hdCHRS-1996RULEATTR dCHRSRULE ATTR xCHRS The Ohm MeterRULEATTR dCHRSRULEATTR dCHRSThe Ohm-meter scale is a non linear scale, hence a logarithmic scale. The scale of the ohmmeter reads oppositely to the D.C./A.C. Voltmeter and D.C. Ammeter scales. RULEATTR dCHRSRULEATTR dCHRSSIMPLE CIRCUIT:RULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSParts required:RULEWATTRW dCHRSW- 1 moving coil meter with 1 mA f.s.d. and 100 Ohms internal resistance (75mm diameter)RULE#ATTR# dCHRS#- 1 fixed resistor of 1000 Ohms (R)RULEQATTRQ dCHRSQ- 1 linear variable resistor from 0 to 1000 Ohms consuming 0.25 to 0.5 Watts (VR)RULEATTR dCHRS- 1 torch battery of 1.5VRULEATTR dCHRS1 connecting wiresRULEATTR dCHRSRULE$BATTR dCHRSV=IRATTR qdCHRS ATTR qdCHRSWhere I = 1.0mA = 0.001AmpsRULEBATTR hdCHRS ATTR hdCHRS ATTR hdCHRS V = 1.5VoltsRULE*BATTR hdCHRS ATTR hdCHRS ATTR( hdCHRS( R = V / I = 1.5 / 0.001 = 1500 OhmsRULEATTR hdCHRSRULEBATTRc hdCHRScFor the 1.5V battery be able to produce a full scale deflection of 1.0 mA, the total circuit resistance should be of 1500 Ohms. Hence the variable resistor should be set at 400Ohms to give a total of 1500Ohms (400 + 100 + 1000). Hence if terminals A and B are connected together, the needle of the Ammeter will read 1.0 mA and this corresponds to 0 Ohms. ATTR$ hdCHRS$Hence at 1mA, resistance AB = 0 OhmsATTR hdCHRS.RULEBATTR hdCHRSIf terminals A and B are disconnected the current will fall to 0 and at this point the needle corresponds to infinite resistance between terminals A and B. ATTR+ hdCHRS+Hence at 0mA, resistance AB = infinite OhmsATTR hdCHRS.RULEATTR hdCHRSRULEBATTRF hdCHRSFIf a resistor of standard value of 1500 Ohms is placed between terminals A and B, the total resistance in the circuit will be 3000 Ohms and the meter will read 0.5 mAmps. At this position, the needle corresponds to 1500 Ohms, and can be marked on the scale. To complete the Ohms scale range, standard value resistors (example ATTR& hdCHRS&post office box of standard resistanceATTR hdCHRS) are connected between terminals A and B and the Ohms scale is marked accordingly depending where the needle points at a particular resistance value.RULEATTR hdCHRSRULEATTR hdCHRSFrom the above one can note that the 0 Ohms position corresponds to maximum current while the infinity position corresponds to 0 Amp current. This explains why the Ohmeter scale is opposite to the Voltmeter Ammeter scale.RULEATTR hdCHRSRULEATTR hdCHRSRULEATTR hdCHRSRULEATTR hdCHRSRULE0ATTR0 hdCHRS0To increase the range of an Ohm meter one should increase the battery Voltage together with the circuit resistance. In the above example, a 15V battery will make the ohmmeter read 10 times the previous range. With a 15V battery, the total resistance of the circuit required to produce 1.0 mAmp f.s.d. is:RULE+,ATTR hdCHRS ATTR* hdCHRS*R = V / I = 15 / 0.001 = 15,000 Ohms. RULEwATTRw hdCHRSwHence a 13kOhms resistor should be added in the circuit if a 15V battery is used to increase the Ohmeter range by x 10.RULEATTR hdCHRSRULEATTR hdCHRSOne should never check a resistor in a circuit with the voltage supply on. Also one must be careful and remember that resistors in parallel cannot be checked in place, but one should disconnect one of its terminals from the circuit before.RULEATTR hdCHRSRULEATTR hdCHRSAs a rule Carbon resistors tend to go high in value with time, and sometimes they become an insulator and so an open circuit. In contrast, paper capacitors tend to have a lower resistance when they get faulty with time.RULEATTR hdCHRSRULE ATTR  hdCHRS OHMS LAW: RULEnATTR hdCHRSOhms Law states that the current is directly proportional to the applied Voltage and inversely proportional to the resistance. V ATTR hdCHRS aATTR hdCHRS I , I ATTR hdCHRS aATTR hdCHRS 1 / R , V = IRRULEATTR hdCHRSRULEATTR hdCHRSRULE ATTRhdCHRSREADING THE OHMETER SCALERULEATTR hdCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRULEATTR dCHRSRMSTRULEATTR dCHRSLMSTRULEATTR dCHRS