Extech Instruments 380942 User manual

INSTRUCTION MANUAL
Model 380942
True RMS AC/DC 30A Mini Clamp-on Meter
•True RMS AC Current and Voltage
•Measure low current with high resolution to 0.1mA AC and 1mA DC
•Auto Power Off
•One touch DCA zero adjust
•MIN/MAX and Data Hold functions
•0.9” (23mm) Jaw diameter
Introduction
Congratulations on your purchase of the Extech Model 380942 DC/AC Clamp Meter.
This meter is shipped fully tested and calibrated and, with proper use, will provide years
of reliable service.
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Specifications
General Specifications
Display 3-3/4 digit (4000 count) LCD with 40 segment bargraph
Functions ACA, DCA, ACV, DCV
Polarity Minus sign ( - ) 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 conditions 4oF to 122oF (-10oC to 50oC); < 85% Relative Humidity
Storage conditions - 4oF to 140oF (-20oC to 60oC); < 75% Relative Humidity
Altitude Operate at less than 2000 meters (for indoor use only)
Power consumption Approximately 10mA DC
Weight 6.2 oz. (190g) including battery
Dimensions 7.2 x 2.5 x 1.4” (183 x 63.6 x 35.6mm) (H x W x D)
Jaw opening 0.9” (23mm)
Standards IEC 1010 Category III 300V, Category II 600V
Range Specifications
Function Range Resolution Accuracy Overload
protect
4000mA 1mA 40A DCDC Current
30A 10mA
± (2.0% + 3d)
100A DC
50/60Hz 40 to 100Hz
400mA 0.1mA ±(1.5% + 5d) ±(2.0% + 5d) 40A AC
50/60Hz 40 to 1kHz
4000mA 1mA ±(2.5% + 5d) ±(3.0% + 5d) 40A AC
AC Current
(True RMS)
30A 10mA ±(2.0% + 5d) ±(2.5% + 5d) 100A AC
DC Voltage 400V 0.1V ± (1.0% + 2d) 1000V DC
50/60Hz 40 to 1kHzAC Voltage
(True RMS) 400V 0.1V ±(1.5% + 4d) ±(2.0% + 5d) 800V AC
Specification Notes
•AC Voltage and Current Crest Factor: < 3
•AC / DC Voltage Input Impedance: 10MΩ
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Meter 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. Positive input terminal for Voltage
9. COM terminal
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Safety Symbols and Information
!Caution ! Refer to the explanation in this Manual
Caution ! Risk of electric shock
Earth (Ground)
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 600V above
earth ground.
4. ALWAYS turn off the power and disconnect the test leads before opening the back to
replace the fuse or batteries.
5. NEVER operate the meter unless the back cover and the battery/fuse door are in place
and fastened securely.
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Operation
AC Current Measurements (True RMS)
WARNING: To avoid electric shock, disconnect the test leads from the meter before
making current measurements.
1) Set the Function switch to the 400mA, 4000mA, or 30A 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. Refer to the diagram at right for the correct way to
enclose a single conductor.
3) Read the AC Current value on the LCD’s digital or bargraph
display.
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 mA or 30A 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 DC Current value on the LCD’s digital or bargraph display.
AC Voltage Measurements (True RMS)
WARNING: To avoid electric shock or damage to the meter, do not make any voltage
measurements that exceed the maximum specified limits.
1) Set the Function switch to the 400V AC position.
2) Insert the test leads to the meter as follows: Red lead to “V” terminal; Black lead to the
COM input.
3) Connect the test leads to the circuit or device under test.
4) Read the AC Voltage value on the LCD’s digital or bargraph display.
DC Voltage Measurements
WARNING: To avoid electric shock or damage to the meter, do not make any voltage
measurements that exceed the maximum specified limits.
1) Set the Function switch to the 400V DC position.
2) Insert the test leads to the meter as follows: Red lead to “V” terminal; Black lead to the
COM input.
3) Connect the test leads to the circuit or device under test.
4) Read the DC Voltage value on the LCD’s digital or bargraph display.
Yes
No
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Advanced Features
Relative Measurements
1) Press the ZERO key. The displayed reading will zero and the word ZERO will appear
on the upper portion of the LCD.
2) All subsequent measurements will now be 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 until the
word ZERO switches off.
4) Note that Relative mode is not available if MIN/MAX mode is enabled.
Data Hold
To freeze the current reading on the LCD, press the Data Hold key. The word HOLD will
appear on the LCD while the meter is in the Data Hold mode. To release the Data Hold
function and return the meter to normal operation, press the Data Hold key again. The
word HOLD will switch off.
MIN/MAX Readings
Pressing the MIN/MAX key allows the meter to display the highest and then 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 is taken higher than the previous MAX or lower than the
previous MIN readings. 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.
Auto Power Off
To extend battery life, the meter will auto power off after 30 minutes of operation. To
resume operation, either turn the meter OFF and then ON again, or press the HOLD
button. To disable the auto power off function, press down the “HOLD” key while turning
the meter on.
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Support line [phone]
Technical support: Extension 200; E-mail: [email protected]
Repair & Returns: Extension 210; E-mail: [e-mail]
Product specifications subject to change without notice
For the latest version of this User Guide, Software updates, and other
Up-to-the-minute product information, visit our website: www.extech.com
Extech Instruments Corporation, 285 Bear Hill Road, Waltham, MA 02451
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 Phillips screw.
3) Lift off the battery compartment cover and replace the two 1.5V AA batteries.
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.
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