USER GUIDE 200A True RMS Open Jaw Clamp Meter with Auto Sensing Technology Model MA260
Introduction Thank you for selecting the Extech MA260 200A True RMS Open Jaw Clamp Meter. The MA260 incorporates Auto Sensing where the measurement type is automatically sensed and configured, no need to turn a dial to select the measurement type or range. For AC Voltage, the Auto‐sense feature also evaluates input signals and adjusts the Input Impedance to eliminate effects of ghost voltages.
CAUTIONS CAUTIONS identify conditions and actions that could cause DAMAGE to the meter or equipment under test. Do not expose the meter to extremes in temperature or high humidity. Safety Symbols that are typically marked on meters and instructions This symbol, adjacent to another symbol, indicates the user must refer to the manual for further information.
Description 1 Meter Description 1. Transformer current measurement jaw 2. Non‐contact Volt‐Detection and AC/DC contact voltage indicator 3. Backlit Multi‐function Display 4. Power/Hold button 5. COM (‐) Terminal 6. Voltage, Resistance (+) Input Terminal 7. Backlight button 8. Finger‐Hand Guard 2 8 3 Note that the battery compartment is located on back of meter Automatic measurement detect 2. Low impedance mode is always active 3. Data Hold 4. Diode test 5. Continuity alert 6.
Operation CAUTIONS Read and understand all WARNING and CAUTION statements listed in the safety section of this manual prior to use. Note that the meter Powers up in the Resistance/Continuity mode. Powering the Meter 1. Press the Power‐Hold button to power the meter. Check batteries if unit fails to power up. 2. Press and hold the Power‐Hold button until OFF appears on the display, release the power button to power off the meter. 3.
Voltage Measurements WARNING: Do not apply > 1000VAC/DC between the meter’s terminals and earth ground CAUTION: When connecting the test leads to the circuit or device under test, connect the black lead before the red; when removing the test leads, remove the red before the black lead. AC Voltage Measurements WARNINGS: The time delay that results from the meter’s automatic sensing circuit (1 to 2 seconds) may cause GFCI circuits to reset and breakers to trip.
DC Voltage Measurements 1. Insert the black test lead banana plug into the negative (COM) jack and the red test lead banana plug into the positive (V/ Ω) jack. 2. Touch the test probe tips to the circuit under test. Be sure to observe the correct polarity (red lead to positive, black lead to negative). 3. Read the voltage in the display. The display will indicate the proper decimal point and value. If the polarity is reversed, the display will show (‐) minus before the value. 4.
Resistance Measurements 1. Insert the black test lead banana plug into the negative (COM) jack. Insert the red test lead banana plug into the positive (V/Ω) jack. 2. 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. 3. Read the resistance in the display. The display will indicate the proper decimal point and value. Continuity Check 1.
Smart Data Hold To freeze the LCD meter reading, press the hold button. While data hold is active, the HOLD display icon appears on the LCD. If no signal is sensed, the meter will flash the HOLD icon several times and automatically exit the Data Hold Mode. From the Data Hold mode, press the data hold button to return to normal operation. The HOLD icon will switch OFF. Note: Data hold is not available when no input is detected.
Maintenance WARNING: To avoid electrical shock, disconnect the meter from any circuit, remove the test leads from the input terminals and turn OFF the meter before opening the case. Do not operate with an open case. Cleaning and Storage Periodically wipe the case with a damp cloth and mild detergent; do not use abrasives or solvents. If the meter is not to be used for 60 days or more, remove the batteries and store them separately. Battery Replacement 1.
Specifications ELECTRICAL SPECIFICATIONS Function Range Max. Resolution AC Current 1.5~200.0AAC 0.1 A Accuracy (of reading) and frequency bandwidth ± (3.0% + 5 digits) 50 to 60Hz ± (0.9% + 3 digits) AC Voltage 1.3V~1000V 0.1 V (50Hz‐60Hz) ± (1.5% + 3 digits) (61Hz‐500Hz) DC Voltage +2.1V ~ 1000V ‐0.7V ~ ‐1000V 0.1 V ± (0.3% + 2 digits) ± (0.3% + 2 digits) Resistance 0~10kΩ 1Ω ± (0.9% + 2 digits) Diode 0.4V~0.8V 0.1 V ± (1.
GENERAL SPECIFCATIONS Display Over‐range indication Conversion rate Maximum conductor size AC V bandwidth AC A bandwidth 4‐digit (9999 count) large scale Multi‐Function LCD “OL” is displayed for resistance and voltage functions 2 updates per second 16mm (0.6”) in diameter 50Hz to 500Hz 50/60Hz Low battery indication is displayed. Meter also displays battery power percentage at startup.
