MARTINDALE MM35 User manual

Martindale Electric will carry out routine calibration (on a chargeable basis)
if the instrument is returned, carriage paid, to the address on the final page
of this document. Alternatively, a chargeable collection and return service is
available.
4.5 Repair & Service
There are no user serviceable parts in this unit. Return to Martindale
Electric Company Ltd if faulty, unless fuse replacement only is necessary.
Our service department will promptly quote to repair any faults that occur
outside the warranty period.
4.6 Storage Conditions
The MM35 should be kept in warm, dry conditions away from direct
sources of heat or sunlight, with the battery removed and in such a manner
as to preserve the working life of the multimeter. It is strongly advised that
the unit is not kept in a tool box where other tools may damage it.
4.7 Warranty
Faults in manufacture and materials are fully guaranteed for 2 years from
date of invoice and will be rectified by us free of charge, provided the unit
has not been tampered with and is returned to us with its housing
unopened. Damage due to dropping, abuse or misuse is not covered by the
guarantee. Nothing in these instructions reduces your statutory rights.
Martindale Electric Company Limited
Metrohm House, Penfold Trading Estate, Watford, WD24 4YY, UK.
Tel: [phone] Fax: [phone]
E-mail: [email protected]
Website: www.martindale-electric.co.uk
© Martindale Electric Company Ltd.
Registered in England No. 3387451. Rev 2. July 2005
MM35 DIGITAL MULTIMETER
MARTINDALE
ELECTRIC
Trusted by professionals
INSTRUCTIONS

SAFETY INFORMATION: Always read before proceeding.
WARNING
These instructions contain information and warnings that are necessary for safe
operation and maintenance of the MM35. It is recommended that you read the
instructions carefully and ensure the contents are understood. Failure to
understand the instructions and comply with warnings and instructions herein
can result in serious injury, damage or even death.
In order to avoid the danger of electrical shock, it is important that proper safety
measures are taken when working with voltages exceeding 30V AC rms, 42V AC
peak or 60V DC. Never exceed the maximum allowable input level for each
function and range. Refer to the specifications for maximum inputs. Never
touch exposed wiring, connections or live circuits.
The MM35 must only be used in conditions and for the purpose which it has
been constructed. Attention should be paid to safety instructions, technical
specifications and use of the MM34 in dry surroundings.
Always inspect your meter, test leads and accessories for any sign of damage
before use. If any abnormal conditions exist (e.g: broken test leads, cracked
case, display not reading, etc.), do not attempt to use it. Do not expose it to
direct sunlight, excessive temperature or moisture.
Keep these instructions for future reference. Updated instructions and product
information are available at: www.martindale-electric.co.uk/instruct.html
SYMBOLS: Equipment complies with relevant EU Directives
AC (Alternating Current)
Ground
Direct Current
Equipment protected by Double Insulation (Class II)
Caution - refer to accompanying documents
Caution - risk of electric shock
4. MAINTENANCE
4.1 Cleaning
Maintenance consists of periodic cleaning and battery replacement.
The exterior of the instrument can be cleaned with a dry clean cloth to
remove any oil, grease or grime. Never use liquid solvents or detergents.
Repairs or servicing not covered in this manual should only be performed
by qualified personnel.
4.2 Battery Replacement
WARNING - To avoid electrical shock, disconnect the test leads and
any input signals before replacing the battery. Replace only with the
same type of battery.
This meter is powered by NEDA type 1604 or equivalent 9V battery. When
the meter displays the “ ” symbol, the battery must be replaced to
maintain proper operation. To replace the battery, remove the three screws
from the back of the meter and open the bottom case, remove the battery
from battery compartment and replace it with a new one.
4.3 Fuse Replacement
If no current measurements are possible, check for a blown overload
protection fuse. There are two fuses: F1 for the µA/mA socket and F2 for
the 10A socket. For access to fuses, remove the three screws from the
back of the meter and open the bottom case. Replace F1 only with the
original type 0.5A/250V, fast acting fuse (part no: FUSE500250).
Replace F2 only with the original type 10A/600V, fast acting ceramic fuse
(part no: FUSE10600).
4.4 Calibration
The recommended calibration interval is 12 months.
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CONTENTS
1 Introduction
1.1 Description
1.2 Unpacking And Inspection
1.3 Battery Installation
2 Technical Specification
3 Operation
3.1 Precautions
3.2 Range Selection
3.3 Hold Button
3.4 DC/AC Button
3.5 Audible Continuity/Diode Button
3.6 Voltage Measurement
3.7 Current Measurement
3.8 Resistance Measurement
3.9.1 Diode Test
3.9.2 Continuity Test
4 Maintenance
4.1 Cleaning
4.2 Battery Replacement
4.3 Fuse Replacement
4.4 Calibration
4.5 Repair & Service
4.6 Storage Conditions
4.7 Warranty
4. Remove power from the circuit, open the circuit path for the
measurement and connect the meter in series with it.
5. Apply power and take the reading shown on the display.
3.8 Resistance measurement
1. Select the resistance (Ω) function.
2. Remove power from the circuit under test.
3. Connect the red test lead to the "VΩ" socket and black lead to "COM"
socket.
4. Connect the test leads to the measurement points and take a reading.
3.9.1 Diode test
1. Select the " " rotary switch position and toggle the " " button
until the " " symbol appears.
2. Remove power from the circuit under test.
3. Connect the red test lead to the "VΩ" socket and black lead to "COM"
socket.
4. Touch the probes across the diode and take a reading, reverse the
probes and again take a reading. For a silicon diode, a value between 0.5
& 0.6 should be obtained in the forward direction, and "1." should be
displayed for the reverse direction. A value of "1." in both directions
indicates open circuit, a reading lower than 0.5 in either direction indicates
a shorted diode.
3.9.2 Continuity test
1. Select the " " rotary switch position and toggle the " " button
until the " " symbol appears.
2. Remove power from the circuit under test.
3. Connect the red test lead to the "VΩ" socket and black lead to "COM"
socket.
4. Connect the test leads to the measurement points. The buzzer sounds
for resistance values less than 20Ω.
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Manual ranging may be selected using the “RANGE” button and a single
short press will maintain the range currently selected. Successive short
pushes of this button will cause the MM35 to “RANGE UP”, selecting the
next highest range with each press. A long press will return the meter to
“AUTORANGE” mode.
3.3 HOLD button
The current reading on the display may be frozen by pressing the “HOLD”
button. A further press will return the meter to its normal continuous reading
mode.
3.4 DC/AC button (A)
This button is used to toggle between AC and DC for current
measurements.
3.5 Audible Continuity/Diode button ( )
Pressing this button will make the meter alternate between the continuity
and diode test functions.
3.6 Voltage measurement
1. Connect the red test lead to the "VΩ" socket, and the black lead to the
"COM" socket.
2. Select either DC (V ) or AC (V~) voltage function using the rotary
switch.
3. Connect the test probes to the unit under test and the meter will
autorange until the best range is selected and a reading is displayed.
4. In the DC function a "-" is displayed for negative readings.
3.7 Current measurement
1. Select one of the three current functions using the rotary switch and use
button A ( / ) to choose either DC or AC. The appropriate symbol
appears at the left hand side of the display.
2. When measuring less than 320mA, connect the red test lead to the
µA/mA socket, and the black lead to the COM socket.
3. For current above 320mA, the red lead should be connected to the 10A
socket.
1. INTRODUCTION
1.1 Description
The MM35 is a general purpose, autoranging digital multimeter with
selectable manual ranging.
Functions include DC & AC voltage, DC & AC current, resistance,
continuity & diode test.
The 10A current range is separately fused and has its own test lead
connection socket. A different connection socket is used for the remaining
current measurements.
Voltage and resistance readings are made with the test leads in the “VΩ”
and “COM” sockets. A central rotary switch is used for manual selection of
the required function and the meter autoranges until the optimum reading
resolution occurs.
1.2 Unpacking & Inspection
Before unpacking the MM35, examine the shipping carton for any sign of
damage. Unpack and inspect the MM35 for any sign of damage. If there is
any damage then consult the supplier immediately.
1.3 Battery Installation
Refer to section 4.2 for battery installation instructions.
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2. TECHNICAL SPECIFICATION
Display: 3.5 digit liquid crystal (LCD), maximum reading 3200 with floating
decimal point. Updates at 2 times per second. A responsive, 34 segment
analogue bargraph is shown below the digital read out.
Polarity: Automatic, implied for positive values, "-" to show negative
readings.
Overrange: O.L is displayed.
Zero: Automatic.
Low battery indication: A " " symbol appears when the voltage drops
below that required for correct operation.
Auto Power Off: After approx. 10 minutes.
Operating: 0 to 50°C @ < 70% relative humidity (RH).
Storage: -20 to 60°C, 0 to 80% RH (battery must be removed).
Temperature coefficient: Add (0.1 x % accuracy) per °C from 0 to 18°C,
and from 28 to 50°C.
Maximum altitude: 2,000m.
Battery: 1 x 9 volt, type PP3, MN1604, NEDA1604, JIS006P, IEC 6F22.
Battery life: 500 hours, typical (Zinc - carbon).
Dimensions: 143 x 68 x 47mm (5.6 x 2.7 x 1.9 inches).
Weight: 206g (7.3oz) with battery fitted.
Included: Set of test leads, 9V battery (fitted) & user manual.
DC VOLTS
Ranges: 320mV, 3.2V, 32V, 320V, 600V.
Resolution: 100µV
Accuracy: below 320mV, ± 1.2% rdg + 1 digit
3.2V range, ± 0.8% rdg + 1 digit
above 3.2V, ± 1.2% rdg + 1 digit
Input impedance: 1000MΩ up to 320mV
11MΩon 3.2V range
10MΩon all other ranges
Overload protection: 600V DC or AC rms.
However, electrical noise or intense electromagnetic fields in the vicinity of
the equipment may disturb the measurement circuit. Measurement
instruments will also respond to unwanted signals that may be present.
Users should exercise care and take appropriate precautions to avoid
misleading results in the presence of electromagnetic interference.
3. OPERATION
3.1. Precautions
Warning: Before using the instrument, read the Safety Information
Section, and examine it for damage or contamination (excessive dirt,
grease, etc.). Check the test leads for any evidence of cracked or
frayed insulation. If any abnormal conditions exist, do not use the
meter.
Warning: When using probes, keep your fingers behind the guards.
Warning: Measuring voltages which exceed the limits of the meter
may damage it and expose the operator to a shock hazard. Always
work within the meter voltage limits indicated on it's front panel.
Warning: Never ground yourself when taking electrical
measurements. Do not touch exposed metal pipes, outlets, fixtures
etc. which may be at ground potential. Keep your body insulated by
wearing dry clothing, rubber shoes or stand on a rubber mat, or other
suitable material.
3.2 Range selection
When the function (for example, AC Volts) has been selected and a signal
is present, the MM35 will autorange until the most suitable range has been
selected. The reading will be displayed and the meter will continue to
change range according to variations in the input.
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AC VOLTS
Ranges: 3.2V, 32V, 320V, 600V.
Resolution: 100µV
Accuracy: ± 2% rdg + 4 digits
Bandwidth: 3.2V, 32V ranges - 50Hz to 200Hz
320V, 600V ranges - 50Hz to 60Hz
Input impedance: 11MΩon 3.2V range
10MΩon all other ranges
Overload protection: 600V DC or AC rms.
DC CURRENT
Ranges: 320µA, 3200µA, 32mA, 320mA, 10A
Accuracy: ± 2% rdg + 1 digit except 10A range
± 3% rdg + 3 digits on 10A range
Voltage burden: 320µA & 32mA ranges: 0.2V
all other ranges: 2V
Input protection: 0.5A: 250V fuse
10A, 600V fuse (10A input)
AC CURRENT
Ranges: 320µA, 3200µA, 32mA, 320mA, 10A
Accuracy: ± 2% rdg + 4 digits except 10A range
± 3.5% rdg + 4 digits on 10A range
Bandwidth: 50Hz to 2kHz
Voltage burden: 320µA & 32mA ranges: 0.2V
all other ranges: 2V
Input protection: 0.5A: 250V fuse
10A, 600V fuse (10A input)
RESISTANCE
Ranges: 320Ω, 3.2kΩ, 32kΩ, 320kΩ, 3.2MΩ, 30MΩ
Resolution: 100mΩ
Accuracy: below 320Ω, ± 2% rdg + 3 digits
320Ωto 320kΩ, ± 1.5% rdg + 3 digits
above 320kΩ, ± 2.5% rdg + 3 digits
above 3.2MΩ, ± 5% rdg + 5 digits
Test current: 320Ωrange < 700µA
3.2kΩrange < 130µA
32kΩrange < 13µA
320kΩrange < 1.3µA
3.2MΩrange < 0.13µA
Overvoltage protection: 500V DC or AC rms.
DIODE TEST
Test current: 500µA (at 0.6V forward voltage)
Resolution: 1mV
Accuracy: ± 10% rdg + 2 digits
Overload protection: 500V DC or AC rms.
CONTINUITY TEST
Range: 320Ω
Resolution: 100mΩ
Audible Tone: <20Ω
Test Current: <700µA
Overload protection: 500V DC or AC rms.
NOTE:
This instrument complies with class ll, overvoltage CAT lll, 600V of the
IEC1010-1 (EN61010-1) standard and pollution degree 2 in accordance
with IEC-664 indoor use.
This instrument also complies with the following European Community
Directives: 89/336/EEC (Electromagnetic Compatibility) and 73/23/EEC
(Low Voltage) as amended by 93/68/EEC (CE Marking).
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