Extech Instruments 380560 User manual

User's Guide
High Resolution Benchtop MilliOhm Meter
Models 380560 and 380562
Introduction
Congratulations on your purchase of the Extech 380560 (117V) or 380562 (220V) High
Resolution MilliOhm Meter. This device offers seven resistance ranges with resolution as
low as 0.01mΩ. The 4-wire Kelvin clip connection ensures optimum accuracy. The built-
in comparator feature offers HI-LO-GO testing. Typical applications include transformer,
motor coil, and PC Board resistance measurements. Careful use of this meter will
provide years of reliable service.

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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 on 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 (781)
890-7440 ext. 210 for authorization or visit our website at www.extech.com (click on ‘Contact Extech’ and go to ‘Service
Department’ to request an RA number). 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.
Specifications
General Specifications
Circuit Custom one-chip LSI microprocessor circuit
Display 0.7" (18 mm) 2000 Count LED Display
Connection type 4-Terminal Kelvin
Measurement ranges Seven ranges (see listing below)
Test voltage 5V DC
Comparator Built-in HI/LO/GO testing with audible beeper
Zero adjust Automatic (no adjustment necessary)
Over-range indication Display reads "1____" when the reading is out of range
Operating Temperature 32°F to 122°F (0°C to 50°C)
Operating Humidity Max. 80% RH
Power Supply 110V (380560) or 220V (380562) ±15%, 50/60Hz
Weight 4.85 lbs (2.2kg)
Dimensions 11 x 8 x 3.5" (280 x 210 x 90mm)
Range Specifications
Range Resolution Test Current Accuracy (%rdg) Test Voltage
20 mΩ0.01mΩ1A ± (0.2% + 6 digits) 2.7V DC
200 mΩ0.1mΩ1A 3.3V DC
2 Ω.001Ω0.1A 3.5V DC
20 Ω.01Ω10mA 4.1V DC
200 Ω0.1 Ω1mA
2K Ω.001kΩ0.1mA
20K Ω.01kΩ10uA
± (0.2% + 4 digits)
4.5V DC
Note: Specifications based on RF Field Strength <3V/m and frequency <30MHz
International Symbols

380560, Version 1.6, 04/03
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F+
S+
F-
S-
White Bands
Meter Description
1. LED Display
2. HI/LO/GO Status Indicators
3. Power and Range pushbuttons
4. Kelvin clip leads
5. SET/TEST and HI/LO pushbuttons
6. Comparator adjustment screws
7. Kelvin clip lead input terminals
Note: The power cable input and audible alert button are on the rear of the instrument.
Measurement Precautions
Ensure that the meter is connected to the correct power source
(110V for model 380560 or 220V for model 380562).
Do not apply voltage to the meter input terminals. Meter damage may result.
Measurement Procedure
1. Connect the Kelvin test leads to the meter.
2. Press the POWER pushbutton to turn power on.
3. Position the SET/TEST pushbutton to the TEST position.
4. To check the meter zero, clip the test leads
together as shown at right.
5. Select the desired measuring range using
the labeled black pushbuttons. When the resistance of the device is unknown, start
with the highest range and work downward.
6. Clip the leads onto the device under test as shown below.
7. Observe the reading on the LED display.
1
2
3
4
5 6 7
Rx
F + S+ S - F -

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
Support Hotline [phone]
Tech support: Ext. 200; Email: [e-mail]
Repair/Returns: Ext. 210; Email: [e-mail]
Website: www.extech.com
Comparator Operation (HI-LO-GO)
The meter is equipped with a Comparator function allowing the user to sort resistance
measurements against programmable HIGH and LOW limits. To program the comparator:
1. Position the SET/TEST pushbutton to SET.
2. Position the LO/HI pushbutton to LO.
3. Adjust the LO comparator screw to the desired low limit (shown on the LED display).
4. Position the LO/HI pushbutton to HI.
5. Adjust the HI comparator screw to the desired high limit.
6. Position the SET/TEST pushbutton to TEST.
7. Set the rear buzzer switch ON or OFF. When ON, the meter will sound an audible tone
for each GO measurement.
Each time a measurement is taken, the appropriate Comparator status LED will light. If the
measurement is lower than the LO setting, the LO LED will light. If the measurement is
higher than the HI setting, the HI LED will light. If the reading is between the HI and LO
settings, the green GO LED will light. If the rear beeper pushbutton is set ON, an audible
tone will sound each time a GO reading is detected.
Measurement Principles
The test current flows through the resistance from the FORCE+ (F+) terminal to the
FORCE- (F-) terminal. The S+ and S- (SENSE) terminals measure the voltage drop across
the device under test only, thus eliminating the lead and contact resistances. The meter
displays the resistance based on the test current and the measured voltage; refer to the
equation below:
Rx = Vx / Is
Where:
Vx is the voltage drop across the device under test;
Is is the test current;
Rx is the resistance of the device under test.
Calibration and Repair Services
Extech offers complete repair and calibration services for all of the products we sell.
For periodic calibration, NIST certification on most products or repair of any Extech
product, call customer service for details on services available. Extech recommends that
calibration be performed on an annual basis to ensure calibration integrity.
Copyright ©2002 Extech Instruments Corporation.
All rights reserved including the right of reproduction in whole or in part in any form.