EXCEL DT9208A Digital Multimeter DC AC Voltage Current Resistance Capacitance Temperature Tester
1. INIRODUCTION
This instrument is compact, rugged, battery operated, handheld 3 1/2digit digital.
multimeter for measuring DC and AC voltage, DC and AC current, Resistance and
Diode, Capacitance, Transistor, continuity Test and temperature or frequency
The Dual-slope A - D Converter uses C - MOS technology for auto - zeroing, polarity
Selection and over - range indication Full overload protection is provided. It is an
Ideal instrument for use in the field, laboratory, workshop, hobby and home
applications.
2.FEATURES
Push-button ON-OFF power switch.
Single 30 position easy to use rotary switch for FUNCTION and RANGE
Selection
High sensitivity of 100µ V.
Automatic overrange indication with the “1”displayed.
Automatic polarity indication on DC ranges.
All ranges fully protected.
Resistance measurements 0.1Ω to 200MΩ.
Capacitance measurements 1 pF to 20µ F.
Diode testing with 1mA fixed current.
Transistor hFE Test With ib -100µA.
Temperature measurement with or without K type thermocouple.
3.SPECIFICATIONS
Accuracies are ± (%reading + No. of digits).
Gurranteed for 1 year, 23C±5C, less than 75%RH.
DC Voltage
|
RANGE |
ACCURACY |
RESOLUTION |
|
200mV |
±0.5%. of rdg ±5 digit |
100µ V. |
|
2V |
1mV |
|
|
20V |
10mV |
|
|
200V |
100mV |
|
|
1000V |
±0.8% of rdg ±2 digit |
5 V |
Input Impedance: 10M ohm on all ranges.
Overload Protection: 1000V dc , or peak ac on all ranges.
AC Voltage
|
RANGE |
ACCURACY |
RESOLUTION |
|
200mV |
±1.2% .of rdg ± 3 digits |
100µV |
|
2V |
±0.8%.of rdg ± 3 digits |
1mV |
|
20V |
10mV |
|
|
200V |
100mV |
|
|
700V |
±1.2%.or rdg ± 3 digits |
1V |
Input Impedance: 10M ohm on all. ranges. .
Frequency Renge: 40Hz to 400Hz.
Overload Protection: 750V rms or 1000V peak continuous on ac ranges, except.
200mV ac range (15 seconds maximum above 300V rms)
Indication: Average (rms of sine wave)
DC Current
|
RANGE |
ACCURACY |
RESOLUTION |
|
2mA |
± 1.2%,or rdg ± 5 digit |
1µA. |
|
20mA |
10µ A |
|
|
200mA |
± 1.2%,or rdg ± 5digits |
100µ A |
|
20A |
± 2%,or rdg ± 5digits |
10mA |
Overload protection: 0.2/250V fuse.(20A range not fused)
Maximum. lnput Current: 20A, 15 sec.
AC CYRREBT
|
RANGE |
ACCURACY |
RESOLUTION |
|
20mA |
± 1.2%,or rdg ± 3digits |
10µ A |
|
200mA |
± 2.0%,of rdg ± 3digits |
100µ A |
|
20A |
± 3%,of rdg ± 7digits |
10mA |
Overload Protection: 0.2A/250V fuse.(20A range not fused.)
Frequency Range: 40Hz to 400Hz.
Maximum Input Current: 20A 15 sec.
Indication: Average (rms of sine wave.)
Resistance
|
RANGE |
ACCURACY |
RESOLUTION |
|
200 ohm |
± 0.8% ,of rdg ± 3 digits |
0.1 ohm |
|
2K ohm |
± 0.8% ,of rdg ± 1 digits |
1 ohm |
|
20K ohm |
10 ohm |
|
|
200K ohm |
100 ohm |
|
|
2M ohm |
1k ohm |
|
|
20M ohm |
± 1% ,of rdg ± 2 digits |
10k ohm |
|
2000M ohm |
±5% ,of (rdg -10 digits) ± 10 digits |
100k ohm |
On 200M ohm range, if short the two test leads, display reading is 10
digits, this 10digits should be subtracted from measurement results.
Capacitance
|
RANGE |
ACCURACY |
RESOLUTION |
|
2000pF |
± 2.5% ,of rdg ± 5 digits |
1 PF |
|
20nF |
10 PF |
|
|
200nF |
100 PF |
|
|
2µ F |
1 nF |
|
|
20µ F |
10 nF |
|
|
200µ F |
± 5% ,of rdg ± 5 digits |
|
Temperature
|
RANGE |
TEMPERATURE RAGE |
ACCURACY |
RESOLUTION |
|
T |
-50C -400C |
±0.75% of rdg ± 3C |
1C |
|
400 C -1000 C |
±1.5% of rdg ± 15C |
1C |
|
|
0C -40C |
±2 C |
1C |
Using T type thermocouple probe
Build - in temperature sensor.
Frequency Test
|
Range |
Accuracy |
Resolution |
|
200KHz |
± 1% of rdg ± 1 dight |
100Hz |
Overload Protection: A C 220 Vrms.
4. GENERAL CHARACTERISTICS
Maximum. Display : 1999 counts (3 1/2digits)with automatic.
polarity indication and eng .unit.
Indication Method : LCD display.
Measuring Method : Dual -Slope integration A - D converter
system
Overrange Indication :”1”Figure only in the display.
Maximum common mode voltage : 500V dc/ac rms.
Reading rate :2-3 reading per sec (approximate) .
Temperature for guaranteed accuracy :23C to± 5C.
Temperature Ranges :Operating 0C to 40C,32° F to.
104° F Storage -10C to 50C,14° F to122° F.
Power Supply :One 9 - volt battery (NEDA 1604 6F22
TYPE or equivalent ).
Low Battery Indication : to left of display
Size :88W × 170D ×38H m/m
Weight : 340g (including 9 volt batteries)
Accessories :Operating manual. Set of test leads
Optional Accessories :Thermocouple (k type,400C) .
Spare fuse (200mA/250V fast below type).
9V Battery (Zinc- Carbon type)(no battery)
Soft Carring case.
5. OPERATION
1. Check the 9 - volt battery by setting the ON - OFF switch to ON. If the battery is
weak,a sign will appear on the display.
It this does not appear on the display, proceed as below. See MAINTENANCE if
the battery has to be replaced .
2. The mark, or sign, next to the test lead jacks, is for warning that the in-
put voltage or current should not exceed the indicated values.
This is to prevent demage to the internal circuity.
3. The function switch should be set to the range which you want to test before operation
4. If the voltage or current range is not known beforehand set the FUNCTION
switch to a high range and work down.
5. When only the figure “1”is displayed, over range is being indicatea and the
FUNCTION switch must be set to a higher range .
5.1) DC Voltage Measurement
1.Connect the BLACK test lead to the COM jack and the .RED test lead to the V/Ωjack.
2. Set the FUNCTION switch to the V=range to be used and connect the test
leads across the source or load under measurement.
The polarity of the RED lead connection will be indicated at the same time as the voltage.
Note:
Do not apply more than 1000v to the input .Indication is possible at
higher voltages but there is danger of damaging the internal circuitry
5.2) AC Voltage Measurement
1.Connect the BLACK test lead to the COM jack and the RED test lead to the V/Ωjack.
2. Set the FUNCTION switch to the V- range to be used and connect the test
leads across the source or load under measurement.
Note:
Do not apply more than700 rms the input .Indication is possible at
higher voltages but there is danger of damaging the internal circuitry
5.3)DC Current Measurement
1.Connect the BLACK test lead to the COM jack and the RED test lead to the
mA jack for a Maximum of 200mA.For a maximum of 20A,move the red test lead to
the 20A jack .
2.Set the FUNCTION switch to the A - range to be used and connect the test leads in
series with the load under measurement .The polarity at the RED test lead connection
will be indicated at the same time as the current.
Note:
The Maximum input current is 200mA ,or 20A depending on the jack used .
Excessive current will blow the fuse which must be replaced .The 20A range is not
protected by protected by a fuse .The fuse rating should be 200mA and no more to
prevent damage to the internal circuitry .The Maximum terminal voltage drop is 200mV.
5.4)AC Current Measurement
1.Connect the BLACK test lead to the COM jack and the RED test lead to the
mA jack for a maximum of 200mA.For a maximum of 20A,move the RED test lead to
the 20A jack .
2.Set the FUNCTION switch to the A - range to be used and connect the test leads in
series with the load under measurement .
Note:
The Maximum input current is 200mA ,or 20A depending upon the jack used .
Excessive current will blow the fuse which must be replaced .The 20A Range is not
protected by a fuse .The fuse rating should be 200mA and no more to prevent damage
to the internal circuitry .
The Maximum terminal voltage drop is 200mV.
5.5)Resistance Measurement
1.Connect the BLACK test lead to the COM jack and the RED test lead to the
V/Ωjack.(Note: The polarity of the RED test lead is “+”)
2.Set the FUNCTION switch to the Ω range to the be used and connect the test
leads across the resistance under measurement.
Note:
1. If the resistance value being measured exceeds the maximum value of the range
selected an over -range indication will be displayed (“1”) Select a higner range .For
resistance of approximately 1 megohm and above , the Meter may take a few
seconds to become stable. This is normal for high resistance readings.
2. When the input is not connected, i. e. at open circuit ,the figure”1”will be displayed
for the over range condition.
3. When checking in - circuit resistance, be sure circuit under test has all power
removed and that all capacitors are fully discharged.
4.200MΩ range open circuit voltage is 3V.Display reading is 10 digits .when test
leads short ,this normal, when measure 10MΩ resistor (on 200MΩ range).display
is 20.measure 100Mohm (on 200M range)display reading is 110.The 10 digits is
a constant and should be subtracted from the reading.
5.6)Capacitance Measurements
1. Before connecting the test capacitor ,note the display which may have readings
other than zero each time the range is changed .This offset reading will not at
fect the accuracy for it can be overridden by true value.
2.Connect the test capacitor to the input sockets (not test leads) noting the polarity
connections when required.
Note:
1.When test individual capacitors insert the eads into the two sockets, with”+”(upper
socket) ,”-” (Lower socket) ,at the left of the pannel .(Capacitors should be
discharged before being inserted into the test -jack).
2.When testing polarized capacitors, for example, the tantalum type, particular
attention must be paid to the polarity connections, This is to prevent possible
damage to the capacitor
When testing large capacitances, note that there will be a certain time lag before the
final indication.
Units 1 pF =10-6µF InF =10-3µF
. Do not connect an external voltage or a charged capacitor (especially larger
capacitors) to the measuring terminals.
5.7)Diode Measurement and Continuity Test
1.Connect the BLACK test lead to the COM jack and the RED test lead to the V/Ωjack
(Note: The polarity of the RED test lead is “+”).
2.Set the FUNCTION switch to the range and connect the test leads across the diode
under measurement, display shows the approx forward voltage of this diode.
3.Connect the test leads to two points of circuit ,if the resistance is lower than approx 30Ω
Buzzer sounds.
5.8) Transistor hFE Test
1.Set, the FUNCTION switch to the hFE range.
2.Datermine whether the transistor is NPN or PNP and locate the Emitter Base and collector
leads into the proper holes in the socket on the front panel.
3.The display will read the approximate hFE value at the test condition Base Current 10µ A
VCE 2.8V.
5.9) Temperature Measurement
1.Measure temperature with K type thermocouple, Set the FUNCTION switch to the T range
and insert the K type thermocouple plug into KPROBE socket
2.Measure ambient temperature without probe .On the same T range. display reading
is the ambient temperature in C.
5.10)Frequency test
1.Connect test Leads or shield cable to COM and F/V/Ωjack.
2.Set the FUNCTION switch to KHZ range ,and connect test leads or cable across the
source or load under measurement .
Note:
1. Do not apply more than 220Vrms to the input ,indication is possible at voltage
voltage higher than 10Vrms ,but readings may be out of specification.
2.In noisy environment it is preferable to use shield cable for measuring small signal.
5.11)Auto Power -off (Optional Function)
Automatic Power-off extends the life of the battery by turning the meter off if no
rotary function switch is operated for about 15 min .The meter turns back on if either
the rotary switch is turned or the power switch is pressed again
6.MAINTENANCE
Battery and /or fuse replacement should only be done aner the test leads have been
disconnected and POWER OFF
6.1)9-Volt Battery Replacement
Note the condition of the 9- volt battery using the procedure described above .if the
battery needs to be replaced, open the back cover remove the spent battery and replace it
with a battery of the same type.
6.2)Fuse Replacement
Should the fuse need replacement use only 200mA fuses identical in physical size to
the original
