Thank you for selecting the Extech MA410 Clamp Meter. This meter measures AC Current, AC/DC
Voltage, Resistance, Capacitance, Frequency, Diode Test, Duty Cycle and Continuity. Custom
features include Thermocouple Temperature and Non-Contact Voltage detection. The double molded
case is designed for heavy duty use. This meter is shipped fully tested and calibrated and, with proper
use, will provide years of reliable service. Extech Instruments is an ISO-9001 Certified company.
Safety
International Safety Symbols
This symbol, adjacent to another symbol or terminal, indicates the user must refer
to the manual for further information.
This symbol, adjacent to a terminal, indicates that, under normal use, hazardous
voltages may be present
Double insulation
WARNING
CAUTION
PER IEC1010 OVERVOLTAGE INSTALLATION CATEGORY
OVERVOLTAGE CATEGORY I
Equipment of OVERVOLTAGE CATEGORY I is equipment for connection to circuits in which
measures are taken to limit the transient over voltages to an appropriate low level.
Note – Examples include protected electronic circuits.
OVERVOLTAGE CATEGORY II
Equipment of OVERVOLTAGE CATEGORY II is energy-consuming equipment to be supplied from
the fixed installation.
Note – Examples include household, office, and laboratory appliances.
OVERVOLTAGE CATEGORY III
Equipment of OVERVOLTAGE CATEGORY III is equipment in fixed installations.
Note – Examples include switches in the fixed installation and some equipment for industrial use
with permanent connection to the fixed installation.
OVERVOLTAGE CATEGORY IV
Equipment of OVERVOLTAGE CATEGORY IV is for use at the origin of the installation.
Note – Examples include electricity meters and primary over-current protection equipment
This WARNING symbol indicates a potentially hazardous situation, which if not
avoided, could result in death or serious injury.
This CAUTION symbol indicates a potentially hazardous situation, which if not
avoided, may result damage to the product.
NOTES: Read and understand all Warning and Caution statements in this operation manual prior
to using this meter. Set the function select switch to the OFF position when the meter is not in use.
Non-Contact Voltage Detector
WARNING: Risk of Electrocution. Before use, always test the Voltage Detector on a known live
1. Rotate the Function switch to any measurement position.
2. Place the detector probe tip on the conductor to be tested.
3. If AC voltage is present, the NCV detector light will turn on with
NOTE: The conductors in electrical cord sets are often twisted. For
NOTE: The detector is designed with high sensitivity. Static
AC Current Measurements
WARNING: Disconnect the test leads before making clamp measurements.
1. Rotate the Function switch to the 400A position
2. Press the trigger to open jaw. Fully enclose
3. Read the current value in the display.
4. If the value is less than 40A, rotate the function
circuit to verify proper operation.
a steady red light.
best results, move the probe tip along a length of the cord to
assure placing the tip in close proximity to the live
conductor.
electricity or other sources of energy may randomly trip the sensor. This is normal operation.
WARNING: To avoid electric shock, discharge the capacitor before measuring.
1. Rotate the function switch to the CAP capacitance position.
2. Insert the black test lead banana plug into the negative COM jack.
Insert the red test lead banana plug into the positive
3. Touch the black test probe tip to one side of the device.
Touch the red test probe tip to the other side of the device.
4. Read the capacitance value in the display.
jack.
Type K Temperature Measurements
1. Rotate the function switch to the °F or °C temperature position.
2. Insert the Temperature Probe into the input jacks.
3. Place the temperature probe tip(s) where needed.
4. Read the temperature on the display.
Note: In case of an open input or a temperature overrange, the meter will display
“OL” .
Data Hold
To freeze the LCD reading, press the HOLD button. The HOLD icon appears on
the LCD. Press the HOLD button again to return to normal operation.
Relative
Press the REL button (REL will appear in the display) to zero the reading and create a reference
point. All future reading will be the difference between the actual reading and the stored “REL”
reading. In the REL mode, autoranging is disabled and measurements are limited to the range
active when the REL button was pressed. Press the REL button to exit the mode.
Note: Relative does not function in Frequency or Duty Cycle mode.
Automatic Power Off
In order to conserve battery life, the meter will automatically turn off after approximately 30 minutes.
To turn the meter on again, change the position of the function switch.
Low battery indication
When the icon appears in the display, the battery should be replaced. Refer to the battery
replacement procedure in the maintenance section.
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 the meter
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 battery and store it
separately.
Battery Replacement
1. Remove the 2 Phillips head screws that secure the rear battery cover
2. Open the battery compartment
3. Replace the 2 AAA 1.5V batteries.
4. Secure the battery compartment door
All EU users are legally bound by the Battery Ordinance to return all used
batteries to community collection points or wherever batteries / accumulators are
sold! Disposal in household trash or refuse is prohibited!
Disposal: Follow the valid legal stipulations in respect of the disposal of the
device at the end of its lifecycle.
Clamp jaw opening 30mm (1.18") approx.
Display 4,000 count LCD
Continuity check Threshold <150; Test current < 0.5mA
Diode test Test current of 0.3mA typical;
Open circuit voltage 1.5VDC typical
Low Battery indication Battery symbol is displayed
Over-range indication ‘OL’ display
Measurement rate 2 readings per second, nominal
Thermocouple sensor Type K thermocouple required
Input Impedance 10M (VDC and VAC)
AC bandwidth 50 to 400Hz (VAC)
AC response True rms
Operating Temperature 5C to 40C (41F to 104F)
Storage Temperature -20C to 60C (-4F to 140F)
Operating Humidity Max 80% up to 31C (87F) decreasing linearly to 50% at 40C
Storage Humidity <80%
Operating Altitude 2000meters (7000ft) maximum.
Battery Two “AAA” 1.5V batteries
Auto power OFF After approx. 30 minutes
Dimensions & Weight 200x66x37mm (7.9x2.6x1.5”); 205g (7.23oz)
Safety For indoor use and in accordance with the requirements for double