Last Revised: 11 December 2017 121GW User Manual CONTENTS Contact ......................5 Glossary of Terms ....................6 Change log ......................7 General ......................8 FCC/IC Information ..................8 Information to the User ................8 Introduction ...................... 9 Features ......................10 Specifications ....................
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Last Revised: 11 December 2017 121GW User Manual Caution ......................24 Operation ......................25 Measuring ....................... 30 Voltage ....................30 Temperature ..................32 Current ..................34 Burden Voltage ..................36 Resistance ..................... 37 Continuity Testing ................38 Cable Break Testing ................
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Last Revised: 11 December 2017 121GW User Manual Temperature .................... 53 Battery Voltage ..................53 Auto Power Off (APO) ................53 LCD Contrast .................... 54 Date......................54 Logging Interval ..................55 Maintenance ....................56 Debugging ....................56 Cleaning and Storage ................... 56 Fuse Replacement ..................
If you have a warranty claim, you can contact us at the following email ad- dress: sales@eevblog.com This multimeter and accessories can be purchased from: www.eevblog.com Community Support for the meter is provided on the EEVblog Forum: www.eevblog.com/forum Phone: Ph: +61(2)86268743...
Last Revised: 11 December 2017 121GW User Manual GLOSSARY OF TERMS (International Electrotechnical Commission) An organisation that publishes various international standards relating to electrical, electronics and related technology. ANSI (American National Standards Institute). Americas non-profit standards organisation that oversee the development and use of standards in various domains.
Last Revised: 11 December 2017 121GW User Manual CHANGE LOG The following represents the changes made to the manual: Date Description 11/12/17 Original Release...
Last Revised: 11 December 2017 121GW User Manual GENERAL FCC/IC INFORMATION This device complies with Part 15 of the FCC Rules and CAN ICES-3(A). Opera- tion is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference re- ceived, including interference that may cause undesired operations.
Last Revised: 11 December 2017 121GW User Manual INTRODUCTION Congratulations on purchasing the EEVblog 121GW multimeter. It's one of the most feature packed small form factor meters on the market, designed to provide maximum functionality in as little bench space as possible. It pro-...
Last Revised: 11 December 2017 121GW User Manual FEATURES Summary • True RMS sensing up to crest factor 10 (AD8436 chipset) • 600 V CAT III ETL Listed Rating • 1000 V HRC fuses • High voltage 15V diode test mode •...
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Last Revised: 11 December 2017 121GW User Manual Software • Android, and Windows 10 support, [iPhone, Mac, Windows Phone] • Updatable Firmware (via micro SD Card) Batteries • RTC Battery (CR1220) • Main Battery (4 x AA) • Long battery life of >500 hrs...
Last Revised: 11 December 2017 121GW User Manual SPECIFICATIONS The following specifications are given in SI units with their accuracy notated as ± (% of reading digits) + (number of digits) unless otherwise indicated. GENERAL The following table represents general specifications (at 23°C ± 5°C):...
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Last Revised: 11 December 2017 121GW User Manual V & Auto V 600 V DC/AC RMS PTC & MOV Protection mV, Ohm & others 600 V DC/AC RMS PTC & MOV Protection Low Battery Voltage Below approx. 4.2 V Battery Type 4 x 1.5 V AA alkaline battery...
Last Revised: 11 December 2017 121GW User Manual VOLTAGE MEASUREMENT The following section provides the specifications Range Resolution Accuracy Test Condition DC V to 500 mV 1 to 10 µV ±0.1% + 10 5 to 500 V 0.1 to 10 mV ±0.05% + 5...
Last Revised: 11 December 2017 121GW User Manual CURRENT MEASUREMENT The following section refers to the current measurement ranges and their re- spective performances. The current measurement module is protected by a 440 mA/1000 V HRC Fuse and an 11 A/1000 V HRC Fuse.
Last Revised: 11 December 2017 121GW User Manual RESISTANCE & CAPACITANCE MEASUREMENT The following section outlines the specifications for the impedance ranges Range Resolution Accuracy R Ω 50 Ω 0.001 Ω ±0.5%+20 500 Ω 0.01 Ω ±0.3%+5 5 to 500 kΩ...
Last Revised: 11 December 2017 121GW User Manual FREQUENCY & DUTY CYCLE MEASUREMENT Range Resolution Accuracy ±0.1%+3 99.999 Hz to 0.001 to 10 Hz 999.99 kHz ±0.2% + 5 + Duty 1 to 99 % 0.1 % 0.2/kHz Cycle This channel has overload protection for up to 600 V.
Last Revised: 11 December 2017 121GW User Manual TEMPERATURE & CONTINUITY Range Resolution Accuracy Temp -200 to 1350°C 0.1°C ±0.5%+3°C °C K-Type Continuity 30 Ω or 300 Ω 10 mΩ Not Specified User Selectable OPEN or CLOSED This channel has overload protection for up to 600 V.
Last Revised: 11 December 2017 121GW User Manual BLUETOOTH SPECIFICATIONS • The 121GW uses a BLE112-A Class 2 certified Low Energy Bluetooth module. • This device complies with Part 15 of the FCC Rules. • This device complies with Industry Canada licence-exempt RSS stand- ard(s).
Last Revised: 11 December 2017 121GW User Manual STANDARDS This Multimeter complies to the following standards. COMPLIANCE SYMBOLS The device is marked with the following symbols, these have the following meanings: Symbol Definition RCM, this is the Regulatory Compliance Mark. It indicates that the product is compliant to required Australian Standards.
Last Revised: 11 December 2017 121GW User Manual The following symbols are used on the device and through this manual to in- dicate whether something is a warning or a precaution. Symbol Definition Caution: Possibility of electric shock Caution: See explanation in section WARNING A condition or action that could result in serious injury or death to the user.
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Last Revised: 11 December 2017 121GW User Manual French: Sécurité Ce manuel contient des informations et des avertissements qui doivent être suivis lors de l'utilisation de l'appareil. En suivant ces instructions, vous proté- gerez d'endommager l'appareil ou de risquer votre bien-être. L'appareil ne peut que vous protéger jusqu'à...
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Last Revised: 11 December 2017 121GW User Manual pièces défectueuses ne doivent pas être utilisées et doivent être remplacées avant utilisation. 4. N'utilisez que des ensembles de sonde homologués UL avec des valeurs nominales supérieures ou égales à celles du compteur.
Last Revised: 11 December 2017 121GW User Manual CAUTION A condition or action that could result in damage or malfunctions in the in- strument. 1. Before changing functions, remove test leads from any measurement point. 2. Before any measurement, ensure test leads are connected to appro- priate connector on the device and in an appropriate manner to the test points.
Last Revised: 11 December 2017 121GW User Manual OPERATION The following section will outline how to operate the device. This section uti- lises some symbols which are defined in the table below:...
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Last Revised: 11 December 2017 121GW User Manual...
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Last Revised: 11 December 2017 121GW User Manual Digital Display: Readings are displayed on dual 4 ⅘ -digit 50,000 count LCD display. One Primary and one smaller secondary function display. The sec- ondary function display is only used when a function that requires it is se- lected.
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Last Revised: 11 December 2017 121GW User Manual RANGE Button: Used to swap between ranges of a function. This could be moving the decimal point for the voltage range, swapping between 3 V or 15 V diode mode etc... HOLD Button: Used to select the Auto HOLD function REL Button: Used to select the relative measurement mode.
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Last Revised: 11 December 2017 121GW User Manual A / 500mA Jack: This input jack is used for the Amps and 500 mA current modes. It is 11 A HRC fused. An input warning alert func- tions for the is jack.
Last Revised: 11 December 2017 121GW User Manual MEASURING VOLTAGE...
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Last Revised: 11 December 2017 121GW User Manual When measuring AC voltages, you need to select the AC mode using the mode button. You will see the AC icon appear on the screen when you are in the correct mode.
Last Revised: 11 December 2017 121GW User Manual TEMPERATURE...
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Last Revised: 11 December 2017 121GW User Manual When measuring temperature be sure to have the leads connected as above and in the correct range. To enter the temperature mode, press the mode button twice after selecting mV on the dial.
Last Revised: 11 December 2017 121GW User Manual CURRENT...
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Last Revised: 11 December 2017 121GW User Manual When measuring current be sure to have the leads connected as above and in the correct range, for higher currents ensure that the red lead is connected to the A 500 mA socket.
Last Revised: 11 December 2017 121GW User Manual URDEN OLTAGE When measuring current on the multimeter there is a voltage drop across the resistor used to measure the current. This voltage is called the “burden volt- age”. To measure the burden voltage, perform the following steps: 1.
Last Revised: 11 December 2017 121GW User Manual RESISTANCE When measuring resistance select the range as shown above with the leads connected as shown above. Resistance is measured between the two leads. Modes Pressing the MODE button will cycle through the following modes: The following modes are available on the resistance range 1.
Last Revised: 11 December 2017 121GW User Manual CONTINUITY TESTING When taking measurements, you must connect the leads as shown above. To check if a short (Selectable <30 Ω or <300 Ω) exists you can use the conti- nuity tester. To use this range, you need to press the MODE button once. To change the continuity threshold level between >30 Ω...
Last Revised: 11 December 2017 121GW User Manual CABLE BREAK TESTING When taking measurements, you must connect the leads as shown above. To check if a break exists (Selectable >30 Ω or >300 Ω) exists you can use the cable break tester. To use this range, you need to select the Continuity mode and: 1.
Last Revised: 11 December 2017 121GW User Manual CAPACITANCE When taking measurements, you must connect the leads as shown above. To enter the capacitance mode, press the MODE button three times. You can zero out the residual lead and meter capacitance with the REL func- tion.
Last Revised: 11 December 2017 121GW User Manual FREQUENCY When taking measurements, you must connect the leads as shown above. Frequency measurement is the default mode for the dial position shown above. Modes Pressing MODE will result in a change in the measurement mode The following modes are available on the frequency range 1.
Last Revised: 11 December 2017 121GW User Manual DUTY CYCLE When taking measurements, you must connect the leads as shown above. To enter the duty cycle mode press mode twice after selecting the Hz dial po- sition.
Last Revised: 11 December 2017 121GW User Manual PERIOD When taking measurements, you must connect the leads as shown above. To enter the period measurement mode press MODE once after selecting the Hz dial position. The period in milliseconds will be displayed.
Last Revised: 11 December 2017 121GW User Manual DIODE MEASUREMENT When taking measurements, you must connect the leads as shown above. The diode measurement range also supports a high voltage mode (up to 15 V) that enables the measurement of Zener voltages, LED string arrays and other similar potentials.
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Last Revised: 11 December 2017 121GW User Manual Voltage mode is toggled between 3 V and 15 V by pressing the RANGE button after selecting the diode measurement mode, the secondary display will then show the maximum diode voltage measurable.
Last Revised: 11 December 2017 121GW User Manual POWER (VA) Power measurements require measurements of both voltage and current, be careful to connect the system in a manner that the common terminal is com- mon for both the voltage measurement and the current measurement.
Last Revised: 11 December 2017 121GW User Manual DATA LOGGING Data logging is started by holding the MEM button until a beep is heard and the MEM icon flashes on screen. Logged data is stored to an internal Micro SD card which is accessible behind the battery cover.
Last Revised: 11 December 2017 121GW User Manual BACKLIGHT To enable the backlight, hold the MODE button. BLUETOOTH To enable Bluetooth communications, hold the “1ms PEAK” button until BT is displayed on the LCD. Ensure that Bluetooth is enabled on the host device before running the appli- cation on the remote computing device.
Last Revised: 11 December 2017 121GW User Manual MEASUREMENT HOLD There are two measurement HOLD functions. 1. Manual Hold To pause the measurement on the main display, press the HOLD button. To resume measurement, you need to press the button again until A- and HOLD are no longer visible.
Last Revised: 11 December 2017 121GW User Manual RELATIVE MEASUREMENT (REL) If you are measuring something relative to another measurement or need to calibrate any non-zero error out you can press the REL button to zero, the currently displayed value.
Last Revised: 11 December 2017 121GW User Manual MIN/MAX/AVG To find the minimum and maximum value found during sampling you can use the MIN/MAX button. This button also provides an average function AVG. This can be entered by pressing the button until the AVG symbol appears.
Last Revised: 11 December 2017 121GW User Manual SETUP MENU To configure and read settings for the multimeter you can press the SETUP button to view the settings. If you press the setup button multiple times you will cycle through the menu, the order of the menu is as follows: 1.
Last Revised: 11 December 2017 121GW User Manual EMPERATURE The multimeter has an internal temperature which can be used for rough am- bient temperature measurement. Note that there will be thermal lag due to the sealed enclosure. It is displayed on the secondary display.
Last Revised: 11 December 2017 121GW User Manual LCD C ONTRAST If the multimeter has ghosted characters you may want to turn the contrast down, if the screen is not dark enough you may need to turn up the contrast.
Last Revised: 11 December 2017 121GW User Manual OGGING NTERVAL The logging interval can range from 200 ms to 999 seconds. If you need to change the interval, then you should: 1. Navigate to the menu item “In x” using SETUP 2.
Last Revised: 11 December 2017 121GW User Manual MAINTENANCE The 121GW maintenance is outlined in this section. Before opening case for maintenance, disconnect test leads from the meter and turn off the meter. DEBUGGING 1. If a low battery alert appears on the device as indicated in the opera- tion section, the back of the device must be opened to replace the AA batteries.
Last Revised: 11 December 2017 121GW User Manual FUSE REPLACEMENT To check whether you need to replace a fuse perform the following steps: 1. Switch to the voltage range and connect a lead as shown in the below diagram. 2. If the multimeter beeps the fuse is functioning, if it fails to beep it indicates that the fuse is blown.
Last Revised: 11 December 2017 121GW User Manual mA/µA current input fuse: 400 mA / 600 V DC/AC, IR 10 kA HRC FAST Designed to UL 248-1 Dimension: 6mm x 32 mm Recommended: ASTM HV610.0.4 400 mA (600V) or HV620.0.4 (1000V)
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Last Revised: 11 December 2017 121GW User Manual 1. Press and hold the MODE button. 2. Turn on device. 3. If the screen says, “CAL 1”. Press REL button, enter calibration mode. 4. The secondary screen will display “CAL” when the device is in calibra- tion mode.
Last Revised: 11 December 2017 121GW User Manual ZERO OFFSET CALIBRATION To calibrate the offset of a mode and range the following procedure must be followed: 1. Follow the steps shown in the section “Cal- ibration Mode”. 2. Disconnect or short the input that would...
Last Revised: 11 December 2017 121GW User Manual FULL SCALE GAIN CALIBRATION Before attempting any full-scale gain calibration, you need to be sure that you have the required reference values for the ranges that calibration is needed. These values are given in the calibration table.
Last Revised: 11 December 2017 121GW User Manual FIRMWARE UPDATE The 121GW features updatable firmware that enables upgrades to be per- formed by the user from the SD card. To perform a firmware update, follow the following procedure: 1. Turn off the multimeter.
121GW User Manual WARRANTY The 121GW is warranted to be free from defects in materials and workman- ship for a period of one year from the date of purchase. If within the war- ranty period your instrument should become inoperative from such defects, the unit will be repaired or replaced at the company’s option.
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