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. INSTRUCTIONS 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, Imperial Park, Imperial Way, Watford, Hertfordshire, WD24 4PP, UK Tel: +44(0)1923 441717 Fax: +44 (0)1923 446900 E-mail:sales@martindale-electric.co.uk 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
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) 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 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. Caution - refer to accompanying documents Caution - risk of electric shock 2 11
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" 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" 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" 4. Connect the test leads to the measurement points. The buzzer sounds for resistance values less than 20Ω. 1 Introduction 1.1 Description 1.2 Unpacking And Inspection 1.3 Battery Installation 2 Technical Specification CONTENTS 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 10 3
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 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. 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" 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 3. For current above 320mA, the red lead should be connected to the 10A 4 9
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. 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 11MΩ on 3.2V range 10MΩ on all other ranges Overload protection: 600V DC or AC rms. 8 5
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: 11MΩ on 3.2V range 10MΩ on 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 320Ω to 320kΩ, ± 1.5% rdg + 3 digits above 320kΩ, ± 2.5% rdg + 3 digits above 3.2MΩ, ± 5% rdg + 5 digits Test current: 320Ω range < 700µA 3.2kΩ range < 130µA 32kΩ range < 13µA 320kΩ range < 1.3µA 3.2MΩ range < 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). 6 7