Clarke CDM35C User manual

OPERATING INSTRUCTIONS
GC0415
DIGITAL MULTIMETER
MODEL NO: CDM35C
PART NO: 4501150

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INTRODUCTION
Thank you for purchasing this CLARKE product.
Before attempting to use this product, please read this manual thoroughly and
follow the instructions carefully. In doing so you will ensure the safety of yourself
and that of others around you, and you can look forward to your purchase
giving you long and satisfactory service.
GUARANTEE
This product is guaranteed against faulty manufacture for a period of 12
months from the date of purchase. Please keep your receipt which will be
required as proof of purchase.
This guarantee is invalid if the product is found to have been abused or
tampered with in any way, or not used for the purpose for which it was
intended.
Faulty goods should be returned to their place of purchase, no product can
be returned to us without prior permission.
This guarantee does not effect your statutory rights.
ENVIRONMENTAL RECYCLING POLICY
Through purchase of this product, the customer is taking on the
obligation to deal with the WEEE in accordance with the WEEE
regulations in relation to the treatment, recycling & recovery and
environmentally sound disposal of the WEEE.
In effect, this means that this product must not be disposed of with general
household waste. It must be disposed of according to the laws governing
Waste Electrical and Electronic Equipment (WEEE) at a recognised disposal
facility.

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SAFETY INFORMATION
BEFORE USE
1. When using the meter, the user must observe all normal safety rules
concerning:
• General protection against electric shock
• Protection of the meter against misuse.
2. When the meter is delivered, confirm it has not been damaged in transit.
3. The test leads must be kept in good condition. Before using, check that the
insulation on the test leads has not been damaged or any wire exposed.
4. Use only the test leads supplied to ensure operational safety. If necessary,
they must be replaced with test leads of the same model or class.
DURING USE
1. Do not take measurements that exceed the maximum values for this
meter.
2. Do not touch the metal probes of the test leads when the meter is
connected to the circuit being measured.
3. Keep your fingers behind the probe barriers when taking measurements.
4. Do not take voltage measurements if you suspect the value exceeds 600V.
5. If the appropriate value range is unknown, select the highest range on the
scale.
6. Disconnect the test leads from the circuit under test before turning the
rotary function selector.
7. Do not measure the resistance, diode or continuity of live circuits.
8. Do not connect the meter to any voltage source while the rotary selector is
in the Current, Resistance, Diode or Continuity range.
9. Do not use the meter near explosive gases or steam.
10. Stop using the meter if any abnormalities or faults are observed.
11. Do not use the meter unless its rear case and battery cover is correctly and
securely fastened.
WARNING: TAKE CARE WHEN USING THIS METER. IMPROPER USE CAN
RESULT IN ELECTRIC SHOCK OR DAMAGE TO THE METER. TAKE ALL
NORMAL SAFETY PRECAUTIONS AND FOLLOW THE SAFEGUARDS
SUGGESTED IN THIS MANUAl.

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12. Do not store or use the meter in areas exposed to direct sunlight, at high
temperature or with high relative humidity.
13. To avoid false readings, replace the batteries as soon as the Low Battery
indicator appears.
14. Before use, verify the meter operation by measuring a known voltage.
15. Never touch exposed wiring, connections or any live circuit while taking
any measurements.
16. Keep your body isolated from ground by using dry clothing, rubber shoes,
rubber mats or any approved insulating material.
SPECIFICATIONS
Product dimensions: (D x W x H) 56 x 94 x 196 mm
Weight (inc battery) 500 g
Test leads length (inc probes) 1000 mm
Max voltage between input & earth 600V
Fuses F1 400mA/600V F2 10A/600V
Power 9V battery
Maximum display value 1999
Over-range indication “1”
Polarity display “-” for negative polarity
Detects and measures voltages DCV 200m/2/20/200 ± 0.5%, 600±0.8%
ACV 200m ± 1.2% 2/20/200 ± 0.8%, 600
± 1.2%
Detects and measures resistance Ohm 200ohm ± 0.8%,2k/20k/ 200k/ 2M
± 8%, 20M ± 1%, 200M ± 6%
Detects and measures current DCA 2µ, 20m± 8%, 200µ± 1.5%,10± 2%
ACA 20µ ± 1%, 200µ± 1.8%, 10± 3%
Detects and measures frequency Hz 20k ± 2%
Operating temperature 0-40°C
Storage temperature 0°C to 60°C
Auto power-off time 20 min

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FEATURES OF THE METER
Feature Description/Use
1 Display Digital LCD
2 Power Button Power ON/OFF.
3 Data Hold
Button
Press the HOLD button. The LCD will hold the last
reading measured and display the Hsymbol. When
the button is released, the meter will return to normal.
4 Rotary Switch Selects different functions and range
The four input sockets are used as follows:
5 mA hFE Positive input socket for current, mA, capacitance and
diode tests (connected via black test probe or used as
a dedicated multifunction test socket)
6COM All common inputs to be measured are connected via
the black test probe or used as a dedicated
multifunction test socket.
7
V.Ω
Positive input socket voltage, resistance, frequency,
diode and buzzer measurement (connected using red
test probe)
8 10A Positive input end of 10A (connected using red test
probe)

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MEASUREMENT FEATURES OF THE METER
• Alternating voltage measurement:- V~
• Direct voltage measurement:- V=
• Alternating current measurement:- A=
• Direct current measurement:- A=
• Resistance measurement:- Ω
•Diodemeasurement:-
• Continuity:-
• Frequency measurement:- Hz
• Transistor gain:- hFE
ITEMS SUPPLIED
• Multi-meter c/w polymer holder & fold-out stand
• Pair of test lead/probes (1 red/1 black)
• 9-volt battery
SAFETY SYMBOLS
Please read all of the safety and operating instructions carefully before using
this product. The following safety symbols may be found on the product.
General hazard
warning
High voltage with
danger.
Earth Class II wiring without
earth conductor.
Possibility of high
voltage

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OPERATION
Before taking the measurement of voltage with the probe, make sure there is
no electronic device connected to the test socket of the instrument.
PREPARATION
1. Switch on the power by turning the rotary switch. If the battery voltage is
lower than 7V, the " " symbol will appear and the battery should be
replaced.
• The " "symbol next to the input lead shows that the input voltage or
current should not exceed the specified value in order to protect the
internal circuit from damage.
2. Turn the rotary switch to the required function and range to be measured.
3. Choose the highest range when the value to be measured is unknown.
• When making a connection, connect the common test lead first and
then the powered test lead.
4. Remove the positive test lead first when disconnecting.
READING HOLD
1. Press "HOLD" button to hold the readings of current measurement.
2. Press the "HOLD" button again to release the hold.
DC/AC VOLTAGE MEASUREMENT
1. Plug the black test lead into the "COM" jack and the red test lead into the
"VTemp Hz" jack.
2. Set the rotary switch to the "V-- " position for DC measurement and "V~" for
AC measurement and at the proper range.
3. Connect the test leads to the voltage source or load for measurement.
4. Read the value on the main indicator of the LCD. The polarity symbol
denotes the polarity of the end connected by the red test lead.
NOTE: At small voltage ranges, unsteady readings will appear before
the test leads make contact with the circuit. This is normal the
meter is highly sensitive. When the test leads are connected to
the circuit, the true reading will be shown.
WARNING: USE CAUTION WHEN MEASUREING HIGH VOLTAGE CIRCUITS
TO AVOID ELECTRICAL SHOCK AND INJURY. DO NOT TEST VOLTAGES
HIGHER THAN 600V DC/600V AC

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NOTE: When "l " is shown on the LCD, it means the measurement has
exceeded the allowable range. A higher range should be
selected.
NOTE: When the scale of the value to be measured is unknown, select
the highest range first and lower the range accordingly.
DC/AC CURRENT MEASUREMENT
1. Plug the black test lead into the "COM" jack.
2. When the current to be measured is under 200mA, plug the red test lead
into the "mA" jack; when the current to be measured is over 200mA but
under 10A, plug the red test lead into the "10A" jack.
3. Set the rotary switch to the "A-" position for DC measurement and "A~" for
AC measurement and at the proper range.
4. Connect the test leads to the circuit.
5. Read the value on the display.
6. The polarity symbol denotes the polarity of the red test lead.
• The polarity symbol denotes the polarity of the red test lead.
NOTE: When ‘1’ is shown on the LCD, it means the measurement has
exceeded the allowable range; a higher range should be
selected.
NOTE: When the scale of the value to be measured is unknown, select
the highest range first and then lower the range accordingly.
NOTE: " " indicates the maximum current of the mA jack is 200mA and
the maximum current of the 10A jack is 10A. At either jack, current
exceeding the limit will blow the fuse.
RESISTANCE MEASUREMENT
Plug the black test lead into the "COM" jack and the red test lead into the "V Ω
Hz" jack.
WARNING: USE CAUTION WHEN MEASURING HIGH VOLTAGE CIRCUITS TO
AVOID ELECTRICAL SHOCK AND INJURY. DO NOT TEST VOLTAGES HIGHER
THAN 600V DC/AC. TO
AVOID ELECTRICAL SHOCK AND INJURY POWER OFF THE CIRCUIT AND
DISCHARGE THE CAPACITANCE BEFORE MEASURING CURRENT.
WARNING: TO AVOID ELECTRICAL SHOCK AND INJURY POWER OFF THE
CIRCUIT AND DISCHARGE THE CAPACITANCE BEFORE MEASURING
RESISTANCE.

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7. Set the rotary switch to the “Ω" position and at the proper range.
8. Connect the test leads to the ends of the resistor or circuit.
9. Read the value on the LCD.
NOTE: When the input is open," 1 " is displayed on the LCD to indicate
overload. For measuring resistance above 1MΩ, it may take a
few seconds to get a steady reading. This is normal for high
resistance measurement.
DIODE
1. Plug the black test lead into the "COM" jack and the red test lead into the
"VΩ" jack.
2. Set the rotary switch to the " " position.
3. Connect the red test lead to the anode and the black test lead to the
cathode of the diode for testing.
4. Read the value on the LCD.
NOTE: The meter will show approximate forward voltage drop of the
diode.
NOTE: When the test leads are reversed or opened, '1' will appear on the
LCD.
CONTINUITY
1. Plug the black test lead into the "COM" jack and the red test lead into the
"VΩHz" jack.
2. Set the rotary switch to the " " position.
3. Connect the test leads to two ends of the circuit. If resistance of the circuit
is less than 50Ω,the built-in buzzer will sound.
TRANSISTOR GAIN
1. Plug the multi-function socket with the "IN" end in the "hFE mA" jack and
the "COM" end in the "COM" jack.
WARNING: TO AVOID ELECTRICAL SHOCK AND INJURY POWER OFF THE
CIRCUIT AND DISCHARGE THE CAPACITANCE BEFORE TESTING
CONTINUITY.
WARNING: TO AVOID ELECTRICAL SHOCK AND INJURY DO NOT TEST WITH
VOLTAGES HIGHER THAN 250V DC/AC.

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2. Set the rotary switch to the "hFE" position and at the correct range.
3. Determine if the transistor to be tested is either and NPN or PNP type, then
insert the three pins of the transistor into the corresponding holes of the
multifunction socket.
4. Read the approximate transistor gain on the LCD.

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TECHNICAL SPECIFICATIONS
DC VOLTAGE
• Max input voltage: 250V DC at 200mV range, 600V DC elsewhere.
• Input impedance: 10MΩ.
NOTE: At small voltage ranges, unsteady readings will appear before the
test leads make contact with the circuit. This is normal since the
meter is highly sensitive. When the test leads connect to the
circuit, the true reading will be shown.
AC VOLTAGE
• Max input voltage: 250V AC at 200mV range, 600V AC elsewhere.
• Input impedance: 10MΩ.
• Frequency response: 200Hz at 600V range, 40-400Hz
• Response: Average (RMS of sine wave)
NOTE: At small voltage ranges, unsteady readings will appear before the
test leads make contact with the circuit. This is normal since the
meter is highly sensitive. When the test leads connect to the
circuit, the true reading will be shown.
Range Resolution Accuracy
200mV 0.1µV
± 0.5% of reading, + 2 digits
2V 1mV
20V 10mV
200V 100mV
600V 1V ± 0.8% of reading, + 2 digits
Range Resolution Accuracy
200mV 0.1mV ± 1.2% of reading, + 3 digits
2V 1mV
± 0.8% of reading, + 3 digits
20V 10mV
200V 100mV
600V 1V ± 1.2% of reading, + 3 digits

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DC CURRENT
• Overload protection: F1 400mA/600V Fuse F2 10A/600V
• 10A range: F2, 10A/600V fuse (quick acting).
• Max input current:
• mA jack (mA range): 200 mA
• 10A jack: 10A
AC CURRENT
• Overload protection: mA ranges: reset table fuse F1, 400mA/600V dc
• 10A range: F2, 10 A/600V fuse
• Max input current: mA jack (mA range) 200mA
• 10A jack: 10A
• Frequency range: 40Hz to 400Hz
• Display: Average (RMS of sine wave)
Range Resolution Accuracy
20µA 0.01µA ± 2.0% of reading, + 5 digits
200µA 0.1µA
± 0.8% of reading, +1 digit
2mA 1µA
20mA 10µA
200mA 100µA ± 1.5% of reading, +1 digit
10A 10mA ± 2% of reading, + 5 digits
Range Resolution Accuracy
20µA 0.01µA ± 2% of reading, + 5 digits
200µA 0.1µA
± 1% of reading, + 5 digits
2mA 1µA
20mA 10µA
200mA 0.1mA ± 1.8% of reading, + 5 digits
10AmA 10mA ± 3% of reading, + 7 digits

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RESISTANCE
• Overload protection: 250V DC/AC Open circuit voltage: DC ≈2.8V.
DIODE TEST
CONTINUITY TEST
TRANSISTOR
Range Resolution Accuracy
200Ω0.1Ω± 0.8% of reading, + 3 digits
2kΩ1Ω
± 0.8% of reading, + 2 digits
20kΩ10Ω
200kΩ100Ω
2MΩ1kΩ
20MΩ10kΩ± 1.0% of reading, + 2 digits
200MΩ100kΩ± 6.0% of reading, +10 digits
Resolution Function
1mV Displaying approximate forward
voltage of diode
Function
Built-in buzzer will sound if resistance is lower than 50Ω
Range Resolution Accuracy
hFE 1hFE approximation
(0-1000)
Base current 10µA Vce is about DC
2.8V

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MAINTENANCE
GENERAL CARE
Never use the meter unless the rear cover is secure.
Clean the housing of the meter only with a damp cloth diipped in a little
detergent but never chemical solution.
In case of any abnormality, stop using the meter and send it for repair.
REPLACING THE BATTERY
1. Turn off the meter.
2. Unscrew the battery cover and remove.
3. Remove the battery and replace with a new one.
4. Clip the battery compartment to the casing and tighten the screw.
REPLACING FUSES
Fuses rarely need replacement. Almost all fuse blows are the result of operator
error. Fuses should be replaced by your Clarke Service Department using the
type(s) stated on page 4.
TEST LEAD REPLACEMENT
Replace the leads if they become damaged.
WARNING: BEFORE REMOVING THE REAR COVER, DISCONNECT THE
PROBES FROM THE CIRCUIT TO BE MEASURED. ENSURE THE COVER IS
TIGHTLY SECURED BEFORE USING THE INSTRUMENT.
WARNING: REPLACE THE TEST LEADS WITH IDENTICAL OR COMPATIBLE
LEADS. LEAD SPEC: 1000V 10A

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DECLARATION OF CONFORMITY