CEM DT-9929 User manual

User's Guide
True RMS Industrial Multimeter

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Introduction
This meter measures AC/DC Voltage, AC/DC Current, Resistance,
Capacitance, Frequency (electrical & electronic), Duty Cycle, Diode
Test, and Continuity plus Thermocouple Temperature. It can store and
recall data. It features a waterproof, rugged design for heavy duty use.
Proper use and care of this meter will provide many years of reliable
service.
Safety This symbol adjacent to another symbol, terminal
or operating device indicates that the operator
must refer to an explanation in the Operating
Instructions to avoid personal injury or damage to
the meter.
This WARNING symbol indicates a potentially
hazardous situation, which if not avoided, could
result in death or serious injury.
This CAUTION symbol indicates a potentially haza
rdous situation, which if not avoided, may result da
mage to the product.
This symbol advises the user that the terminal(s)
so marked must not be connected to a circuit point
at which the voltage with respect to earth ground
exceeds (in this case) 1000 VAC or VDC.
This symbol adjacent to one or more terminals
identifies them as being associated with ranges
that may, in normal use, be subjected to
particularly hazardous voltages. For maximum
safety, the meter and its test leads should not be
handled when these terminals are energized.
This symbol indicates that a device is protected
throughout by double insulation or reinforced
insulation.
WARNING
CAUTION
MAX
1000V

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PER IEC1010 OVERVOLTAGE INSTALLATION CATEGORY
OVERVOLTAGE CATEGORY I
Equipment of OVERVOLTAGE CATEGORY I is equipment for
connection to circuits in which measures are taken to limit the
transient overvoltages to an appropriate low level.
Note –Examples include protected electronic circuits.
OVERVOLTAGE CATEGORY II
Equipment of OVERVOLTAGE CATEGORY II is energy-consuming
equipment to be supplied from the fixed installation.
Note –Examples include household, office, and laboratory appliances.
OVERVOLTAGE CATEGORY III
Equipment of OVERVOLTAGE CATEGORY III is equipment in fixed
installations.
Note –Examples include switches in the fixed installation and some
equipment for industrial use with permanent connection to the fixed
installation.
OVERVOLTAGE CATEGORY IV
Equipment of OVERVOLTAGE CATEGORY IV is for use at the
origin of the installation.
Note –Examples include electricity meters and primary over-
current protection equipment

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SAFETY INSTRUCTIONS
This meter has been designed for safe use, but must be operated with
caution. The rules listed below must be carefully followed for safe
operation.
1. NEVER apply voltage or current to the meter that exceeds the
specified maximum:
Input Protection Limits
Function
Maximum Input
V DC or V AC
1000VDC/AC rms
mAAC/DC
500mA 1000V fast acting fuse
AAC/DC
10A 1000V fast acting fuse (20A
for 30 seconds max every 15
minutes)
Frequency, Resistance,
Capacitance, Duty Cycle,
Diode Test, Continuity
1000VDC/AC rms
Temperature
1000VDC/AC rms
Surge Protection: 8kV peak per IEC 61010
2. USE EXTREME CAUTION when working with high voltages.
3. DO NOT measure voltage if the voltage on the "COM" input jack
exceeds 1000V above earth ground.
4. NEVER connect the meter leads across a voltage source while
the function switch is in the current, resistance, or diode mode.
Doing so can damage the meter.
5. ALWAYS discharge filter capacitors in power supplies and
disconnect the power when making resistance or diode tests.

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6. ALWAYS turn off the power and disconnect the test leads before
opening the covers to replace the fuse or batteries.
7. NEVER operate the meter unless the back cover and the battery
and fuse covers are in place and fastened securely.
If the equipment is used in a manner not specified by the
manufacturer, the protection provided by the equipment may be
impaired.
Controls and Jacks
1. 40,000 count LCD display
2. STORE(<RECALL) button
3. MAX/MIN (_)button
4. MODE button
5. RANGE(SETUP) button
6. Function switch
7. mA, µA and 10A input jacks
8. COM input jack
9. Positive input jack
10. Backlight button
11. EXIT(AC+DC) button
12. HOLD(PEAKHOLD>) button
13. REL(+) button
Note: Tilt stand and battery compartment are on rear of unit.

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Symbols and Annunciators
•))) Continuity
Diode test
Battery status
n nano (10-9) (capacitance)
µ micro (10-6) (amps, cap)
m milli (10-3) (volts, amps)
A Amps
k kilo (103) (ohms)
F Farads (capacitance)
M mega (106) (ohms)
 Ohms PEAK Peak Hold
Hz Hertz (frequency) V Volts
% Percent (duty ratio) REL Relative
AC Alternating current AUTO Autoranging
DC Direct current HOLD Display hold
ºF Degrees Fahrenheit ºC Degrees Centigrade
MAX Maximum MIN Minimum
N0. Serial number
S second
left auxiliary display
right auxiliary display
SET Set up parameter
AC +DC Alternating current + Direct current
TRMS Ture RMS
STO Store
RCL Recall
AUTO Auto Range
Timing symbol
Backlight
bargraph

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Operating Instructions
WARNING: Risk of electrocution. High-voltage circuits, both AC and
DC, are very dangerous and should be measured with great care.
1.ALWAYS turn the function switch to the OFF position when the
meter is not in use.
2.If “OL”appears in the display during a measurement, the value
exceeds the range you have selected. Change to a higher range.
DC VOLTAGE MEASUREMENTS
CAUTION: Do not measure DC voltages if a motor on the circuit
is being switched ON or OFF. Large voltage surges may occur
that can damage the meter.
1. Set the function switch to the green VDC position.
2. Insert the black test lead banana plug into the
negative COM jack.
Insert the red test lead banana plug into the
positive Vjack.
3. Touch the black test probe tip to the negative
side of the circuit.
Touch the red test probe tip to the positive side
of the circuit.
4. Read the voltage in the display.

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AC VOLTAGE (FREQUENCY, DUTY CYCLE) MEASUREMENTS
WARNING: Risk of Electrocution. The probe tips may not be long
enough to contact the live parts inside some 240V outlets for
appliances because the contacts are recessed deep in the outlets.
As a result, the reading may show 0 volts when the outlet actually
has voltage on it. Make sure the probe tips are touching the metal
contacts inside the outlet before assuming that no voltage is
present.
CAUTION: Do not measure AC voltages if a motor on the circuit
is being switched ON or OFF. Large voltage surges may occur
that can damage the meter.
1. Set the function switch to the green
VAC/Hz/% position.
2. Insert the black test lead banana plug into
the negative COM jack.
Insert red test lead banana plug into the
positive Vjack.
3. Touch the black test probe tip to the neutral
side of the circuit.
Touch the red test probe tip to the “hot” side
of the circuit.
4. Read the voltage in the main display and the
frequency in the right auxiliary display
5. Press the MODE button to indicate “Hz”.
6. Read the frequency in the main display.
7. Press the MODE button again to indicate “%”.
8. Read the % of duty cycle in the main display.
9. Press EXIT for 2 seconds into the function of AC+DC. Test DC
and AC TURE Rms.

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MV VOLTAGE MEASUREMENTS
CAUTION: Do not measure mV voltages if a motor on the circuit
is being switched ON or OFF. Large voltage surges may occur
that can damage the meter.
1. Set the function switch to the green mV position.
2. Press the MODE button to indicate “DC”.or
““AC ”, or in AC range press EXIT for two
seconds and chose ”AC+DC”
3. Insert the black test lead banana plug into the
negative COM jack.
Insert the red test lead banana plug into the
positive Vjack.
4. Touch the black test probe tip to the negative
side of the circuit.
Touch the red test probe tip to the positive side of the circuit.
5. Read the mV voltage in the display.

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DC CURRENT MEASUREMENTS
CAUTION: Do not make 20A current measurements for longer
than 30 seconds. Exceeding 30 seconds may cause damage to
the meter and/or the test leads.
1. Insert the black test lead banana plug into the
negative COM jack.
2. For current measurements up to 4000µA DC,
set the function switch to the yellow µA
position and insert the red test lead banana
plug into the µA/mA jack.
3. For current measurements up to 400mA DC,
set the function switch to the yellow mA
position and insert the red test lead banana
plug into the µA/mA jack.
4. For current measurements up to 20A DC, set
the function switch to the yellow 10A/HZ/%
position and insert the red test lead banana
plug into the 10A jack.
5. Press the MODE button to indicate “DC” on the display.
6. Remove power from the circuit under test, then open up the
circuit at the point where you wish to measure current.
7. Touch the black test probe tip to the negative side of the circuit.
Touch the red test probe tip to the positive side of the circuit.
8. Apply power to the circuit.
9. Read the current in the display.

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AC CURRENT (FREQUENCY, DUTY CYCLE) MEASUREMENTS
CAUTION: Do not make 20A current measurements for longer
than 30 seconds. Exceeding 30 seconds may cause damage to
the meter and/or the test leads.
1. Insert the black test lead banana plug into the
negative COM jack.
2. For current measurements up to 4000µA AC,
set the function switch to the yellow µA position
and insert the red test lead banana plug into the
µA/mA jack.
3. For current measurements up to 400mA AC, set
the function switch to the yellow mA position
and insert the red test lead banana plug into the
µA/mA jack.
4. For current measurements up to 20A AC, set
the function switch to the yellow 10A/HZ/%
position and insert the red test lead banana plug
into the 10A jack.
5. Press the MODE button to indicate “AC” on the display.
6. Remove power from the circuit under test, then open up the
circuit at the point where you wish to measure current.
7. Touch the black test probe tip to the neutral side of the circuit.
Touch the red test probe tip to the “hot” side of the circuit.
8. Apply power to the circuit.
9. Read the current in the display. In the 10AAC range, right
auxiliary display frequency.
10. Press and hold the MODE button to indicate “Hz”.
11. Read the frequency in the display.
12. Momentarily press the MODE button again to indicate “%”.
13. Read the % duty cycle in the display.
14. Press and hold the MODE button to return to current
measurement.
15. Press EXIT for 2 seconds into the function of AC+DC. Test DC
and AC TURE Rms.

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RESISTANCE MEASUREMENTS
WARNING: To avoid electric shock, disconnect power to the unit
under test and discharge all capacitors before taking any
resistance measurements. Remove the batteries and unplug the
line cords.
1. Set the function switch to the green
Ω CAP position.
2. Insert the black test lead banana plug into
the negative COM jack.
Insert the red test lead banana plug into the
positive jack.
3. Press the MODE button to indicate “” on
the display.
4. Touch the test probe tips across the circuit
or part under test. It is best to disconnect
one side of the part under test so the rest of
the circuit will not interfere with the
resistance reading.
5. Read the resistance in the display.

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CONTINUITY CHECK
WARNING: To avoid electric shock, never measure continuity on
circuits or wires that have voltage on them.
1. Set the function switch to the green
ΩCAP position.
2. Insert the black lead banana plug into the
negative COM jack.
Insert the red test lead banana plug into the
positive jack.
3. Press the MODE button to indicate“ " and
“Ω” on the display
4. Touch the test probe tips to the circuit or wire
you wish to check.
5. If the resistance is less than approximately
35, the audible signal will sound. If the circuit is open, the
display will indicate “OL”.
DIODE TEST
1. Set the function switch to the green ΩCAP
position.
2. Insert the black test lead banana plug into the
negative COM jack and the red test lead
banana plug into the positive Vjack.
3. Press the MODE button to indicate“ “ and
“V” on the display.
4. Touch the test probes to the diode under test.
Forward voltage will typically indicate 0.400 to
0.700V. Reverse voltage will indicate “OL”.
Shorted devices will indicate near 0V and an
open device will indicate “OL” in both
polarities.

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CAPACITANCE MEASUREMENTS
WARNING: To avoid electric shock, disconnect power to the unit
under test and discharge all capacitors before taking any
capacitance measurements. Remove the batteries and unplug the
line cords.
1. Set the rotary function switch to the
green ΩCAP position.
2. Insert the black test lead banana plug
into the negative COM jack.
3. Insert the red test lead banana plug into
the positive Vjack.
4. Press the MODE button to indicate “F”
5. Touch the test leads to the capacitor to
be tested.
Read the capacitance value in the
Display
TEMPERATURE MEASUREMENTS
1. Set the function switch to the green
Temp position.
2. Insert the Temperature Probe into the
input jacks, making sure to observe the
correct polarity.
3. Press the MODE button to indicate “ºF”
or “ºC”
4. Touch the Temperature Probe head to
the part whose temperature you wish to
measure. Keep the probe touching the
part under test until the reading
stabilizes (about 30 seconds).
5. Read the temperature in the display.
Note: The temperature probe is fitted with a type K mini connector.
A mini connector to banana connector adaptor is supplied for
connection to the input banana jacks.

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FREQUENCY (DUTY CYCLE) MEASUREMENTS (ELECTRONIC)
1. Set the rotary function switch to the green Hz/% position.
2. Insert the black lead banana plug into the
negative COM jack and the red test lead banana
plug into the positive Hz jack.
3. Touch the test probe tips to the circuit under test.
4. Read the frequency on the display.
5. Press the MODE button to indicate “%”.
6. Read the % duty cycle in the display.
% 4 –20mA MEASUREMENTS
1. Set up and connect as described for DC mA measurements.
2. Set the rotary function switch to the 4-20mA% position.
3. The meter will display loop current as a % with 0mA=-25%,
4mA=0%, 20mA=100%, and 24mA=125%.
AUTORANGING/MANUAL RANGE SELECTION
When the meter is first turned on, it automatically goes into
AutoRanging. This automatically selects the best range for the
measurements being made and is generally the best mode for most
measurements. For measurement situations requiring that a range
be manually selected, perform the following:
1.Press the RANGE key. The “AUTO” display indicator will turn off.
2. Press the RANGE key to step through the available ranges until
you select the range you want.
3. To exit the Manual Ranging mode and return to Autoranging,
press EXIT
Note: Manual ranging does not apply for the Temperature functions.

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MAX/MIN
1.Press the MAX/MIN key to activate the MAX/MIN recording mode.
The display icon "MAX" will appear. The meterleft auxiliary
displaywill display and hold the maximum reading and will update
only when a new “max” occurs.The display icon "MIN" will appear.
The right auxiliary displaymeter will display and hold the minimum
reading and will update only when a new “min” occurs.
2.To exit MAX/MIN mode press EXIT
RELATIVE MODE
The relative measurement feature allows you to make
measurements relative to a stored reference value. A reference
voltage, current, etc. can be stored and measurements made in
comparison to that value. The displayed value is the difference
between the reference value and the measured value. Note:
Relative mode does not operate in the 4-20mA function.
1. Perform the measurement as described in the operating
instructions.
2. Press the REL button to store the reading in the display and the
"REL" indicator will appear on the display.
3. Left auxiliary display display the margin of initial value and the
current value.
Right auxiliary display display the initial reading. Main display the
reading after REL TEST.
4. Press the EXIT button to exit the relative mode.
Display Backlight
Press the key to turn the backlight on. The backlight will
automatically turn off after SET time. Press the EXIT button to
exit the backlight on mode.
HOLD
The hold function freezes the reading in the display. Press the
HOLD key momentarily to activate or to exit the HOLD function.

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PEAK HOLD
The Peak Hold function captures the peak AC or DC voltage or
current. The meter can capture negative or positive peaks as fast
as 1 millisecond in duration. Momentarily press the PEAK button,
“PEAK” and “MAX” will display in left auxiliary display. MIN” will
display in right auxiliary display. The meter will update the dispay
each time a lower negative peak occurs. Press the EXIT button to
exit the PEAK HOLD mode. Auto Power Off feature will be
disabled automatically in this mode.
Data record（STORE/RECALL ）
1、STORE function
In the current testing mode, press STORE button one time, enter
into STORE function.
On the left upper corner of LCD shows NO XXXX.，
which states current storage serial number.
Then, press button PEAKHOLD to change into the initial serial nu
mber 0000. (Press again it will change back).
On the right upper corner of LCD shows XXXX ，which states
how many current storage is used.
Press STORE button again, enter into recording interval time set
up function.
On the left upper shows 0000 S ,which states recording interval
time; using button + & - to select，the range is 0~255 seconds。
When the recording interval time is 0000 S，then press STORE
button again to change into manual recording. Press the STORE
button again to record once.
When the recording interval time is 1~255 S，then press STORE
button again to start recording automatically from 0000.
Recording times is showed on the left upper corner, data is
showed on the right upper corner（Due to digitally limitation,
there is only display preceding four numbers）

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To finish above STORE function, press EXIT button shortly.
If you want to clean all the memory data, the steps are:
When power on, press the EXIT button long time, and then turn
the switch from OFF to random, and release the EXIT button, the
LCD will flash thrice and meantime buzzer thrice, which meansall
memory data have been cleaned.
2 RECALL function
Press STORE button two seconds to enter into RECALL function.
On the left upper corner shows XXXX ，which states current
storage serial number. On the right upper corner shows XXXX ，
which states how many current storage is used.
Press button PEAKHOLD shortly once to scan data from 0000 to
XXXX continuously.
Press again then scan again.
Use button + & —to select serial number XXXX on the left upper
corner and record data on the right upper corner.
To finish above RECALL function, press EXIT button.
Parameter setting up（SET）
1 Press the RANGE button second seconds to enter into SET
function. Then press shortly once, change on setting content.
Setting content includes(in sequence)：
A: upper limit buzzer alarm
B: lower limit buzzer alarm
C: auto power off time
D: turn off phonating
E: back lit time
Use ←、+、-、→ buttons to select the parameter
2 Press SET button continuously to switch to setting content, till
exiting set up to testing mode. So the updated setting content is
saved. If press EXIT button in this period, all setting cann’t be
saved.

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AC+DC
In all the measuring mode VAC,mV(AC),10A(AC),mA(AC),uA(AC),
press button EXIT for 2seconds to enters intoAC+DC testing. The
precision is the same as AC measure. LCD shows AC+DC signal.
Press button EXIT to exit.
LOW BATTERY INDICATION
When the icon appears alone in the display , the battery
should be replaced.
Maintenance
WARNING: To avoid electric shock, disconnect the test leads from
any source of voltage before removing the back cover or the battery
or fuse covers.
WARNING: To avoid electric shock, do not operate your meter until
the battery and fuse covers are in place and fastened securely.
This MultiMeter is designed to provide years of dependable service, if
the following care instructions are performed:
1.KEEP THE METER DRY. If it gets wet, wipe it off.
2.USE AND STORE THE METER IN NORMAL TEMPERATURES.
Temperature extremes can shorten the life of the electronic parts
and distort or melt plastic parts.
3.HANDLE THE METER GENTLY AND CAREFULLY. Dropping it
can damage the electronic parts or the case.
4.KEEP THE METER CLEAN. Wipe the case occasionally with a
damp cloth. DO NOT use chemicals, cleaning solvents, or
detergents.
5.USE ONLY FRESH BATTERIES OF THE RECOMMENDED
SIZE AND TYPE. Remove old or weak batteries so they do not
leak and damage the unit.