UNI-T UT33B Operating Manual

UT33 B/C/D OPERATING MANUAL
UNI-T
UT33B/C/D
Operating Manual
Palm Size Digital Multimeter
SafetyInformation
This Meter compli e swith the standards IEC61010: in poll u tion
deg ree2, overvol t age
category(CAT 1600V, CAT II 300V)and double insulation,
CAT. I: Signal level, special equipment or part s of equipment,
telecommunication,electronic, etc., with smaller transi e nt
overvol t ages than overvoltages CAT. II.
CAT. II: Local level, appliance, PORTABLE EOU EHT ele. ,
with smallertransient overvol t ages than CAT.
IU
Use the Mete r only as specified in this opera'
otherwise the protection provided by the e
S f
impaired.
In this manual, a Waming identifies con ditions
and
aclioos
pose hazards to the use r, or may damage the er
or
equipment under test. A Note identifies theinfonnation Ihal
user
should payattentionon.
Intemational electrical symbols used on the Me ter andin this
Operating Ma nualareexplainedonpege 10.
Rules
For
SafeOperation
.<!> Waming
Toavoid possibleelec tric shock or persona •
to
avoid possible damage to the Met e r or to the equipme
undertest, adhere to thefollowing rules:
• Befor e using the Met e r inspectthe case. Donot usethe
Meter if it is damaged or the case (or part of the case) is
removed. Lookfor cracksor missing plastic.Payattention
to the insulation around the connectors.
• Inspect the test leads for damaged insulation or
exposed metal. Check the test leads for continuity.
Replace damaged test leads with identical model number
or electrical specifications beforeusing
the
Meter.
• Donot apply morethan the rated voltage . as marlted on
the Meter , between the terminals or between any terminal
andgrounding ,
• Therotary switch should be placed in the right position
and no any changeover of range shall be made during
measurement is conducted to prevent damage of the
Meter.
• When the Meterworlting at an effecti v e voltage over 60V
in DCor 42V rms in AC, specia l care should be taken for
thereis dangerof electric shock.
• Usethe propertermi n als, function, and rangefor your
measurements.
• Do not use or store the Meter in an environment of
high temperature, humidity, explosive, inflammable and
strong magnet i c field.The performance of the Metermay
deteri o rateafterdampened.
• When using thetest leads, keepyour fingers behi n d the
fingerguards .
• Disconnect circuit poweranddischa rge all high-voltage
capacitors before testing resistance, continuity, diodes
andcurrent.
• Before measuring current, checkthe Meter ' s fuses and
tum off powerto the circuit beforeconnecting the Me ter to
the circuit.
• Replac e the battery as soon as the battery indicator
appears.With a low battery , the Meter might produce
false
readings that can lead to electric shock and personal
injury.
• Remove test leads and temperature probe from the
Meter and turn the Meter power off before opening the
Metercase ,
• When servicing the Meter, use only the same model
numberor identical electrical specificationsreplacement
parts,
• The internal circuit of the Metershall not be attered at
will to avoiddamage of the Meterandany aceld e
• Soft cloth and mild detergent should be used to de
the surfac e of the Meter when servicing. No abras M! and
solventshould be usedto prevent the surfaceof the Mete r
from corrosion, damage andaccident.
• The eter is suitablefor indoor use.
• Tum the Meteroff when it is not in use and take out the battery
whennot using for a long time.
• Constantly check the battery as it mayleakwhenit has been using
for some time, replacethe battery as soon as leaking appears. A
leaking battery will damage the Meter .
~
-
ACor OC
~
LowBattery
ACCurrent -+I- Diode
ocCurrent
-
Fuse
•
Ear.h Ground
>'1)
Co ntin uityTest
a
llotilIe Insulated l!>
Safety Ruless
cs
Con/orms to Standards of Eu
NV
an Un ion
The eter Structure(figure 1)
1)
2)
6
3) DisDIav Bad<IIchI Button
4}
5)
6)
7)
Figure 1
ss once enter m e.
• Press HOLD agom to exit hold mode.
• In
H<*l mod e,l:Iis displayde an thepresent value
shown .
• Press BLUE buttononceto tumthedisplay backlight
on.
• PressBLUE button again to tumthe display backlight
off.
• Display backlight willNO T beautomatically offunless
pressing theBLUE button.
indicated for information about the functional button
I
BLUE button
Measurement Operation
A. DCVoItage asurem ent(seefigure 2)
Figure2
.<!> Warning
To avoi d harms to you or damages to the Meter from electric shock,
pleasedo not attempt to measure voltages higherthan 500V although
readings may beobtained.
The DC Voltage rang es are : 200mV, 2000mV, 20V,200 V and
soev
To
measml OC • connecttheMe ter asfollows:
1. Insert the red
test
leadinto theVQmAtermina l and theblack testlead
into the COM .
2. Set
the rotary
swtch
kl
an appropriate measurement position in V::=
range.
3. Connect the Ieslleads across
the
obj e ctbei n g measured.
The measured
:.ows
on display.
be
obtained.
Val I agl ' lIl!aSlJrement (see figure 2)
..,oId hanm to you or damages to the Meter from electric shock,
The
AC
valage
are: 200V
and
SOOV.
Tomeasure
AC~'
connect
the
eteras foIows:
1. lnsert theredtestleadinto the VQmA termi n al and theblacktes t lead
intotheCOMterm inal.
2. Set therotary swi t ch to an appropriate measurementpos iti o nin V ­
range.
3. Connectthetest leads across with theobjectbeing measured .
Themeasured value sho wson thedispla y, which is effective value of sine
wav e (mea n valueresponse).
Note
• If the value of voltage to be measured is unknown , use the
max imum measurement pos ition (500V) and reduce the range
stepbystepuntil a sat i sfactory reading is obtained.
• TheLCD displays "1" indicating the existing selected range is
ove rload, it is required to select a higherran gein order to obtai n a
corre ct reading .
• In each range, the Meter has an input impedance of app rox.
10MQ . Thisloading effe ct can cause measurement errors in high
impedan cecircuits. If thecircuitimpedance is lessthan or equal to
1OkQ, theerroris negligible (0.1 % orless).
• When AC vollage measurement has been completed,
disconnect the connection between the testing leads and the
circ uitunder tesl.
C. DCCurrentMeasurement (see figure 3)
Figure 3
.<!> Warning
Neverattempt an in-circuit current measurement where the
voltage betweenterminals and ground is greaterthan 60V.
If the fuse burns out during measurement,the Me ter may be
damaged or the operator himself may be hurt. Use proper
terminals,function,and range for the measureme nt.W hen the
testing leadsare connectedto the current terminals, do not
para llel themacross anycircuit.
TheModel UT33B: thecurrent measurement has 3 measurement
positions
on
the
rotary swi t ch: 200!, A, 200mAand l OA.
The Model UT33CIUT33D : the current measurement has 4
measurementpositi o ns on the rotary switch: 2000,uA, 20mA,
200 mAand10A
Tomeasure current, dothefollowing:
1.
Turn off power to the circuit. Discharge all high-voltage
capacitors.
2. Insert thered lestlead into theVQmA or lOAterminal andthe
black testleadintotheCO Mterminal.
3.-set
the
rotaryswitchto an appropriate measurement positionin
A:= range.
4.
Brea curr e ntpath to betested.Connect thered test lead to
the
more
p<lSlIjW sid e of the break andthe black testlead to the
more negative SIde of break.
5. Tum onpower to
the
cirtuil.
Themeasure d value shows on
the
display.
Note
• If the value of current 1 0 be measured is unknown, use the
maxi m u m measurement position(10A)
• andreducetherange stepbystep unti l a satisfactoryreading is
obtai n ed.
• When current measurement has bee n completed.disconnect
theconneclionbetween thetesting leads
• andthecircuit under test.
D. Measuring Resistance (seefigure 4)
Figure 4
.<!> Warning
To avoid damages to the Meteror to the devices under test,
disconnect circuit powe r and dischargeall the high-voltage
capaci t ors before measuring resistance. ­
The Model UT33B/UT33C: The resistance measurement
positions are: 200Q , 2000Q,20kQ, 200kQ and20MQ.
TheModelUT33D: Theresistance measurement positionsare:
200Q , 2000Q, 20kQ, 200kQ,20MQ and 200MQ
Tomeasure resistance, connect theMeter as follows:
1. Insert the red test lead intothe VQmA terminal and theblack
testlead intotheCOM terminal.
2. Settherotary switch to anapp ropriate measurementpositionin
Q range.
3. Connect thetestleads across wi t htheobje ct beingmeasured.
The measured value shows onthedisplay.
Note
• The test leadscan add 0.1Q to 0.3Q of errorto resistance
eas rement. Toobtain precisio n readings in low-re sistance
measurement. that is the range of 200Q.short-circuit the input
terminals beforehand andrecord thereading obtained (called this
readinaas
Xl. (Xl
Is theadditional resistance from thetestlead.