Analog Multimeter.pdf

Analog Multimeter

1. Prepared by: Mr. John Lexter L. Emberador
Analog Multimeter

2. Lesson Objectives
Attheendofthelesson,thestudentwill
beableto:
1.Identifythedifferentpartsofanalog
multimeter;
2.Performthemensurationandcalculationof
differentinstrumentsusedinelectronics
servicing;and
3.Appreciatetheimportanceofthelessonas
practicalskillsinelectronics.

3. Analog Multimeter
•Ithasamovingcoilassemblywhichis
characterizedbyaneedlepointer.The
advantageofanalogmultimeteroverdigital
multimeterisaresistancetestintesting
electroniccomponentssuchascapacitorand
transistor.

4. Parts of Analog Multimeter

5. Inside Analog Multimeter

6. Steps in using Analog Multimeter
1.Connectthetestprobetotheappropriate
jack.
•Theredtestprobetothe(+)jackandblacktest
probetothe(-)COMjack.

7. Steps in using Analog Multimeter
2.Checkifthepointerrestsexactlyatthezero
positionorinfinitepositionatohmmeterrange.

8. Steps in using Analog Multimeter
Zero Corrector
•Ifthisoccurs,youshould
turnthezero-correctorscrew
incounterclockwisedirection
untilthepointerpointsat
zerovoltagerange.
Wrong Pointer Setting
•Ifthepointerpointsnot
exactlytotheinfinityat
ohmmeterreading,this
causesinaccuracytothe
measuredvalue.

9. Steps in using Analog Multimeter
3.Checktheaccuracyoftheohmmeterby
touchingtwotestprobes.
•Setthemultimetertox1Ωorx10Ωselector
resistancerange.
•Holdthetwotestprobessimultaneously.
Thepointershouldnot
deflectwhenholding
thetwotestprobeat
x1orx10ohmrange.

10. Steps in using Analog Multimeter
4.ChecktheprobesiftheyareOK(Ohmmeter
Calibration)
a.Setthemultimetertocorrespondingselector
resistancerange.
b.Shortthetwotestprobesleadtogether.
Thepointershould
deflecttowardszero
ohmreading.

11. Steps in using Analog Multimeter

12. Steps in using Analog Multimeter
Asindicated,thepointerrests
outoftherangeofohmmeter
scale.Adjusttheohm
adjustmentcounterclockwise
untilthepointerrestsat“0”
ohmreading.
Ifthepointerdidnotdeflectat
all,checktheprobes.Thereisa
possibilitythatoneisbrokenor
openatsomepoint.

13. Resistance Measurement
Ohmmeter Ranges
x1kΩ
x100Ω
x10Ω
x1Ω
Minor
Divisions
Equivalent
0-2 0.2
2-10 0.5
10-20 1
20-50 2
50-100 5
100-200 20
Note:Theminordivisionsof
analogmultimetermayvary
dependingonthebrand.

14. Voltage Measurement
•Settheselectorknobtotheproperscale
range.Thechosenscalerangemustbehigher
thantheanticipatedvoltagetobemeasured.

15. AC Voltage Measurement
•IntestingACvoltages,itdoesn’tmatterifthe
testprobesareinterchanged.
Range
Major
Division
Minor
Division
10 2 0.2
50 10 1
250 50 5
1000 200 20

16. DC Voltage Measurement
•BecarefulintestingDCvoltages,especiallyin
polarity.Besurethatthepositivetestprobe
(red)isconnecedatthepositivesupplyvoltage
andthenegativetestprobe(black)is
connectedatthenegativeorcommonground
ofthesupplyvoltage.

17. DC Voltage Measurement
Range
Major
Division
Minor
Division
0.1 0.02 0.002
0.25 0.05 0.005
2.5 0.5 0.05
10 2 0.2
50 10 1
250 50 5
1000 200 20

18. AC/DC Voltage Measurement

19. DCCurrent Measurement
•Asyousee,theammeterscaleisthesameas
thevoltmeterscale.Applythesameprocedure
inmeasuringvoltage.However,incurrent
measurement,themetermustbeconnectedin
serieswiththecircuit.Unlikeinmeasuring
voltage,theconnectionisinparallel.

20. DCCurrent Measurement
Range
Major
Division
Minor
Division
50uA 10 1
2.5mA 0.5 0.05
25mA 5 0.5
0.25A 0.05 0.005

21. THANKYOU!