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 builtin 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. 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 Display Connection type Measurement ranges Test voltage Comparator Zero adjust Custom one-chip LSI microprocessor circuit 0.8" (20 mm) 2000 Count LED Display 4-Terminal Kelvin Seven ranges (see listing below) 5V DC Built-in HI/LO/GO testing with audible beeper Automatic (no adjustment necessary) Over-range indication Operating Temperature Operating Humidity Power Supply Weight Dimensions Display reads "1____" when the reading is out of range 32°F to 122°F (0°C to 50°C) Max. 80% RH 110V (380560) or 220V (380562) ±15%, 50/60Hz 4.85 lbs (2.2kg) 11 x 8.3 x 3.5" (280 x 210 x 90mm) Range Specifications Range Resolution Test Current Accuracy (%rdg) Test Voltage 20 mΩ 0.01mΩ 1A ± (0.2% + 6 digits) 2.7V DC 200 mΩ 0.1mΩ 1A 3.3V DC 2Ω .001Ω 0.1A 3.5V DC 20 Ω .01Ω 10mA 4.1V DC 200 Ω 0.1 Ω 1mA 2K Ω .001kΩ 0.1mA ± (0.2% + 4 digits) 4.5V DC 10uA 20K Ω .01kΩ Note: Specifications based on RF Field Strength <3V/m and frequency <30MHz International Symbols 2 380560, Version 1.7, 01/07 Meter Description 1. LED Display 2. HI/LO/GO Status Indicators 1 3. Power and Range pushbuttons 2 4. Kelvin clip leads 3 5. SET/TEST and HI/LO pushbuttons 6. Comparator adjustment screws 7. Kelvin clip lead input terminals 4 5 6 7 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. F+ F- S+ S- White Bands 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. F+ S+ S- F- Rx 3 380560, Version 1.7, 01/07 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. Support Hotline (781) 890-7440 Tech support: Ext. 200; Email: [email protected] Repair/Returns: Ext. 210; Email: [email protected] Website: www.extech.com Copyright © 2002 Extech Instruments Corporation. All rights reserved including the right of reproduction in whole or in part in any form. 4 380560, Version 1.7, 01/07