Extech Instruments 380941 User manual

User Guide
AC/DC Mini Clamp Meter
Model 380941
•Large 3 3/4 digit LCD display with 40 segment bargraph
•Continuity and Frequency Measurements
•One touch DCA zero adjust
•MIN/MAX and Data Hold functions
•0.9” (23mm) Jaw diameter
Introduction
Congratulations on your purchase of Extech’s DC/AC Clamp Meter. This professional meter,
with proper care, will provide years of safe reliable service.
www.burntec.com

380941 V3.1 10/06
2
Specifications
General Specifications
Display 3-3/4 (4000 count) Digit LCD with 40 segment bargraph
Functions ACA, DCA, ACV, DCV, Resistance, Frequency, Continuity
Polarity “-“ indicates negative polarity
Current sensor Hall effect sensor type
Overload indication Left blinking digit
DCA zero adjust One touch zero key
Display rate 2 readings/second (20 readings/second for bargraph)
Battery Two 1.5V AA batteries
Operating temperature 4oF to 122oF (-10oC to 50oC)
Operating humidity < 85% RH
Power consumption Approximately 10mA DC
Weight 8 oz. (225g) including battery
Dimensions 7 x 1.75 x 1.25” (178 x 45 x 32mm) (HWD)
Jaw opening 0.9” (23mm)
Standards IEC 1010 Category III 300V, Category II 600V
Range Specifications
Function Range Resolution. Accuracy Overload
protect
40A 10mA ±(1.0% +2dgts) 400A DC
0 to 150A 100mA ±(1.0% +2dgts) 400A DC
DC Current
150 to 200A 100mA ±(2.2% +2dgts) 400A DC
50/60Hz 40 to 400Hz
40A 10mA ±(1.0% +3dgts) ±(1.5% +4dgts) 400A AC
0 to 150A 100mA ±(1.0% +3dgts) ±(1.5% +4dgts) 400A AC
AC Current
150 to 200A 100mA ±(2.2% +3dgts) ±(2.5% ±4dgts) 400A AC
DC Voltage 400V 0.1V ±(1.0% +2dgts) 1000VDC
50/60Hz 40 to 400HzAC Voltage
400V 0.1V ±(1.5% +2dgts) ±(2.0% +4dgts) 800V AC
Resistance 40 to 400Ω0.1 ±(1.0% +2dgts) Beeper <38Ω600V AC
Frequency 100 to 10k 0.01Hz ±0.5% ±2dgts Sensitivity;
2V, 0.1A AC
600V AC
www.burntec.com

380941 V3.1 10/06
3
Front Panel Description
1. Current sense jaw
2. Measurement Trigger
3. Function switch
4. Data Hold key
5. Max Min key
6. One-touch DCA zero key
7. LCD Display
8. 40 segment bargraph display
9. Positive input terminal for V, HZ and Ω
10. COM terminal
International Symbols
!Caution ! Refer to the explanation in this Manual
Caution ! Risk of electric shock
Earth (Ground)
Safety
This meter has been designed to be safe in use, but the operator must use caution in its
operation. The rules listed below should be carefully followed for safe operation.
1. NEVER apply voltage or current to the meter that exceeds the specified maximum:
2. USE EXTREME CAUTION when working with high voltages.
3. DO NOT measure voltage if the voltage on the "COM" input jack exceeds 500V above
earth ground.
4. NEVER connect the meter leads across a voltage source while the function switch is
in the current, resistance or diode mode; doing so can damage the meter.
5. ALWAYS discharge filter capacitors in power supplies and disconnect the power
when making resistance or diode tests.
6. ALWAYS turn off the power and disconnect the test leads before opening the back to
replace the fuse or batteries.
7. NEVER operate the meter unless the back cover and the battery/fuse door are in
place and fastened securely.
www.burntec.com

380941 V3.1 10/06
4
Operation
AC Current Measurements
WARNING: To avoid electric shock, disconnect the test leads from the meter before
making current measurements.
1) Set the Function switch to the 40 or 200A AC range.
2) Press the jaw trigger and clamp around, fully enclosing a single conductor. Do not
allow a gap between the two halves of the jaw.
3) Read the ACA value on the LCD.
DC Current Measurements
WARNING: To avoid electric shock, disconnect the test leads from the meter before
making current measurements.
1) Set the Function switch to the 40 or 200A DC range.
2) Press the DCA zero key to null the meter display.
3) Press the Trigger to open the current sense Jaw.
4) Fully enclose the conductor to be measured. Do not allow a gap between the two
halves of the jaw.
5) Read the DCA value on the LCD.
AC Voltage Measurements
WARNING: To avoid electric shock or damage to the meter, do not make any voltage
measurements that exceed the maximum specified.
1) Set the Function switch to the VAC position.
2) Insert the test leads to the meter as follows: Red lead to “V,Hz,Ω” terminal; Black
lead to the COM input.
3) With the pointed end of the test leads measure voltage. Remember that voltage
measurements are made in parallel with the device or circuit under test.
4) Read the ACV value on the LCD.
DC Voltage Measurements
WARNING: To avoid electric shock or damage to the meter, do not make any voltage
measurements that exceed the maximum specified.
1) Set the Function switch to the VDC position.
2) Insert the test leads to the meter as follows: Red lead to “V,Hz,Ω” terminal; Black
lead to the COM input.
3) With the pointed end of the test leads measure voltage. Remember that voltage
measurements are made in parallel with the device or circuit under test.
4) Read the DCV value on the LCD.
Resistance and Continuity Measurements
WARNING: To avoid electric shock or damage to the meter, remove power to the circuit
under test and discharge all capacitors.
1) Set the Function switch to the Ωposition.
2) Insert the test leads to the meter as follows: Red lead to “V,Hz,Ω” terminal; Black
lead to the COM input.
3) With the pointed end of the test leads measure resistance. Remember that
resistance measurements are made in parallel with the device or circuit under test.
4) Read the resistance value on the LCD.
5) If the resistance is less than 40Ω, the continuity beeper will sound.
www.burntec.com

380941 V3.1 10/06
5
Frequency Measurements
1) Ensure that at least 0.1A AC is detectable with an ACA measurement before
measuring Frequency.
2) Set the Function switch to the Hz position.
3) Insert the test leads to the meter as follows: Red lead to “V,Hz,Ω” terminal; Black
lead to the COM input.
4) With the pointed end of the test leads measure frequency
5) Read the Frequency measurement on the LCD in Hz.
Additional Features
Relative Measurements
1) Press the Zero key and the present measurement will Zero.
2) All subsequent measurements are displayed with respect to the zeroed reading. For
example, if a 20A reading is zeroed and a 30A reading is subsequently measured,
the LCD will display 10A.
3) To return to normal operation, press and hold the zero key for 2 seconds.
4) Note that Relative mode is not available if the MIN/MAX mode is enabled.
Data Hold
To freeze a reading on the LCD, press the Data Hold key. The HOLD icon will appear
and the measurement will be held on the meter’s LCD. To release the Data Hold
function and return the meter to normal operation, press the Data Hold key again.
MIN/MAX Reading Mode
Pressing the MIN/MAX key allows the meter to display ONLY the highest and the lowest
readings encountered. Press the MIN/MAX key once to view the minimum reading,
press it again to view the maximum reading. Note that the meter will only change its
displayed reading when a measurement higher than the previous MAX or lower than the
previous MIN readings is encountered. The HOLD display icon (along with the MIN or
MAX icon) will appear on the LCD in MIN/MAX mode. Pressing the MIN/MAX key a 3rd
time returns the meter to normal operation.
www.burntec.com

380941 V3.1 10/06
6
Maintenance
Battery Replacement
1) When the low battery symbol appears on the LCD the batteries must be replaced.
2) Turn the meter off and remove the rear battery compartment screw.
3) Remove the battery compartment cover and replace the two 1.5V AA cells.
4) Replace the compartment cover and secure the screw.
Cleaning
Caution: Use only a dry cloth to clean the plastic case.
Calibration and Repair Services
Extech offers repair and calibration services for the products we sell. Extech also
provides NIST certification for most products. Call the Customer Service Department for
information on calibration services available for this product. Extech recommends that
annual calibrations be performed to verify meter performance and accuracy.
Warranty
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects
in parts and workmanship for one year from date of shipment (a six month limited warranty
applies to sensors and cables). If it should become necessary to return the instrument for
service during or beyond the warranty period, contact the Customer Service Department at
[phone] ext. 210 for authorization or visit our website www.extech.com for contact
information. A Return Authorization (RA) number must be issued before any product is
returned to Extech. The sender is responsible for shipping charges, freight, insurance and
proper packaging to prevent damage in transit. This warranty does not apply to defects
resulting from action of the user such as misuse, improper wiring, operation outside of
specification, improper maintenance or repair, or unauthorized modification. Extech
specifically disclaims any implied warranties or merchantability or fitness for a specific
purpose and will not be liable for any direct, indirect, incidental or consequential damages.
Extech's total liability is limited to repair or replacement of the product. The warranty set
forth above is inclusive and no other warranty, whether written or oral, is expressed or
implied.
Copyright ©2006 Extech Instruments Corporation. All rights reserved including the
right of reproduction in whole or in part in any form.
www.burntec.com