DLRO2 Ducter™ Low Resistance Ohmmeter 2 A User Guide
This document is copyright of: Megger Limited, Archcliffe Road, Dover, Kent CT17 9EN. ENGLAND T +44 (0)1304 502101 F +44 (0)1304 207342 www.megger.com Megger Ltd reserves the right to alter the specification of its products from time to time without notice. Although every effort is made to ensure the accuracy of the information contained within this document it is not warranted or represented by Megger Ltd. to be a complete and up - to - date description.
This manual supersedes all previous issues of this manual. Please ensure that you are using the most recent issue of this document. Destroy any copies that are of an older issue. Declaration of Conformity Hereby, Megger Instruments Limited declares that radio equipment manufactured by Megger Instruments Limited described in this user guide is in compliance with Directive 2014/53/EU.
Contents Contents 1. Introduction.................................................................................................................................... 2 1.1 Product Description.................................................................................................................................. 2 1.2 Features..................................................................................................................................................... 2 1.2.1 1.
Contents 6. Tests, Resistance mode................................................................................................................... 20 6.1 Auto-start, bidirectional / unidirectional resistance mode.................................................................... 20 6.1.1 Post auto-start, unidirectional test........................................................................................................... 21 6.1.2 Post auto-start, bidirectional test..........................
Contents 13. Calibration, Repair and Warranty............................................................................................... 38 13.1 14. Decommissioning......................................................................................................................... 39 14.1 WEEE Directive....................................................................................................................................... 39 14.2 Battery disposal...............................
Contents www.megger.
Introduction 1. Introduction This user guide details the operational and functional details of the Megger DLRO2 Ducter Low Resistance Ohmmeter 2 A. Please read this user guide fully before attempting to use the DLRO2. 1.1 Product Description The DLRO2 is a tough and truly hand held 2 A low resistance ohmmeter, designed to provide fast, accurate and repeatable measurements even in electrically noisy environments.
Introduction 1.3 Applications The DLRO2 measures low resistance values in applications ranging from railways and aircraft to resistance of components in industry. Any metallic joint can be measured but users must be aware of measurement limitations depending on application. For example, if a cable manufacturer plans to make resistive measurements on a thin wire, a low test current should be selected to prevent heating the wire thereby changing its resistance.
Introduction 1.4 Company web site Occasionally an information bulletin may be issued via the Megger web site. This may concern new accessories, new usage instructions or a software update. Please occasionally check on the Megger web site for anything applicable to your Megger instruments. www.megger.com 4 DLRO2 www.megger.
Safety Warnings 2. Safety Warnings The safety instructions given in this document are indicative of safe practice and are not to be considered exhaustive. Additionally, they are not intended to replace local safety procedures in the region where the instrument is used. If the equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be impaired. There are no user replaceable parts within the DLRO2. 2.
Safety Warnings The voltage indicator and current discharge features must be regarded as additional safety features and MUST not substitute the normal safe working practice which MUST be followed. The instrument must not be used if any part of it is damaged or if the terminal shutter is missing. The circuit under test must be switched off, de-energized, securely isolated and proved dead before test connections are made.
Safety Warnings 2.5 Safety, Hazard and Warning Symbols on the Instrument This paragraph details the various safety and hazard icons on the instrument’s outer case. Icon Description Warning: High Voltage, risk of electric shock Caution: Refer to User Guide. Equipment complies with current EU directives. Equipment complies with current ‘C tick’ requirements. Do not dispose of in the normal waste stream. Equipment protected throughout by double insulation. IP54 IP rating 2.5.
Instrument Controls 3. Instrument Controls 3.1 Instrument Layout Front View Rear View 1 10 2 3 6 4 5 7 8 11 9 12 Item 8 Description Item Description 1 External electrical connections. Refer to 3.4.
Instrument Controls 3.2 Instrument Display 2 3 4 5 1 6 16 7 15 8 14 9 13 10 12 11 Item Description Item Description 1 Difference Meter. Refer to 3.
Instrument Controls 3.3 Instrument Rotary Control 2 1 3 4 Item Description 5 Item Description Rotary switch positions 10 1 Inductive mode 4 Long leads mode 2 Resistance mode 5 Settings mode (grey) 3 Off position DLRO2 www.megger.
Instrument Controls 3.4 Instrument connections and leads 3.4.1 External electrical connections of DLRO2 Slider to front Slider to back 1 1 3 4 2 5 6 7 Item Description 7 Item Description 1 Rear attachment point for strap 4 Slider in rear position 2 Slider in front position 5 Battery charger connection 3 Connections: C1, P1, P2, C2 6 USB port (firmware update) 7 Front www.megger.
Instrument Controls 3.5 The Difference Meter The Difference Meter is a feature on the DLOR2 that is displayed at the top of the primary screen (marked ‘1’ on the diagram). The Difference Meter works in inductive and resistive modes only. It can be toggled off and on in the instrument settings, giving space for other characters in the primary field to be displayed in a larger format making them easier to read, if required. Refer to 9.1 General Settings on page 28.
Instrument Controls 3.5.1 Difference Meter example of operation This explanation of the Difference Meter is written in reference to resistance mode but the explanation applies equally to inductive mode. Resistance measurement is selected. The Difference Meter is inactive. Continuity is indicated for C and P leads First measurement is complete. The Difference Meter is now active. The first measurement is shown as a green ring at the centre of the scale with +0% below.
Instrument Controls Fourth measurement is made, the Difference Meter shows it’s result, again relative to the first measurement. The new reading is -1% showing a possible return to the expected result. Note: The units on the main display have changed back to µΩ and are shown in blue indicating another change. Fifth measurement is made, the Difference Meter shows it’s result, relative to the reference measurement. This reading is now just -1% lower than the reference measurement.
Setting up the DLRO2 4. Setting up the DLRO2 Before each use visually inspect all equipment about to be used. Check the instrument is in good condition and there is no visible damage to either the instrument or the test leads. Confirm the instrument case, test leads and connectors are in good condition with no damaged or broken insulation 4.1 Warnings and exception conditions Refer to 8. Error and Warning Conditions on page 27. 4.2 Power 4.2.
Tests, Inductive mode 5. Tests, Inductive mode Inductive test mode allows users to measure resistance of an inductive load (i.e. motors, small power transformers, etc.). Note: Test current can measure up to 1 A. Note: Pre-charging; before any measurement can be made, the circuit needs to be ‘pre-charged’. This is carried out at a low current (1 mA) and is indicated on the display by an animated sequence of chevrons (< << <<< <<<<). The animation will be displayed until the pre-charge phase is complete.
Tests, Inductive mode 4. To start the test press the TEST button. Resistance and current values continually up date on screen. The current starts at 1 mA and can reach a maximum of 1 A if a higher current is required for the resistance being measured. End of the test To stop the test press the TEST button. Note: The TICK button ( ) will set a new reference value. Warning: Do not disconnect test leads until discharge is completed. During the discharge phase, the buttons and rotary switch will be inactive.
Tests, Inductive mode 5.2 Auto stop 1. Turn rotary switch to select the inductive mode position. 5.2.1 First test Inductive test screen appears, ‘Inductive Mode’ shows in secondary field for a short time then disappears. Note: Soft key 1 toggles MANUAL / AUTO. 2. Select AUTO on soft key 1. 3. Connect C1-C2 and P1-P2 to the instrument and the unit under test. for no C and P indicators show red background with continuity or green background with for good continuity. Proceed when both show .
Tests, Inductive mode 4. To start the test press the TEST button. During the test results will live update on screen. The test will stop automatically when the instrument determines that the reading has been stable for long enough and is unlikely to change significantly; the user can override the instrument and stop the test at any time by pressing the TEST button. The Difference Meter is active. When the test is stopped the displayed result is static.
Tests, Resistance mode 6. Tests, Resistance mode Resistance mode measures the resistance of a unit under test in a forward current direction (unidirectional mode) or forward and reverse direction (bidirectional mode). In manual start mode, the test will be carried out when the TEST button is pressed. In auto start mode the DLRO2 will start the test automatically as soon as continuity is detected, however it will not automatically start testing if continuity is established before the test mode is selected.
Tests, Resistance mode The dashes (or an old result) will flash until a new result is displayed. During the test, continuity indicators will fade and soft keys will be inactive. For bidirectional tests, the dashes (or the previous result) and left hand arrow will flash while the instrument performs a reading in the forward direction.
Tests, Resistance mode 6.2 Manual, bidirectional / unidirectional resistance mode 1. Turn rotary switch to select either the bidirectional resistance mode position or unidirectional resistance mode position. OR Resistance test screen appears, ‘Bidirectional Resistance Mode’ or ‘Unidirectional Resistance Mode’ shows in secondary field for a short time then disappears. Note: Soft key 1 toggles continuous / single test.
Tests, Resistance mode 6.2.1 For a unidirectional test: As the test starts, continuity indicators will fade. Dashes or previous value will flash on the main display until result appears. On the secondary display dashes or previous results will flash until a new result is ready. The soft keys will not operate during this test. 6.2.2 For a bidirectional test: As the test starts, continuity indicators will fade.
Tests, Long leads mode 7. Tests, Long leads mode Long leads resistance test mode has been designed for use with test leads of very long length. The Difference Meter is disabled in long leads mode. All readings are displayed in mΩ. Minimum current is 1 A. Restricted to single tests. In long leads mode, all soft keys are inactive. The test is pre-set to single measurement, 1 A with previous 2 results displayed. 7.1 Long leads mode - auto and manual start OR 1.
Tests, Long leads mode 7.1.1 For manual mode Proceed when both show green background with . 3. To start the test press the TEST button. During the test, continuity indicators will fade. The dashes (or an old result) will flash until a new result is displayed. On the secondary display dashes or previous results will flash until a new result is ready. For a single test the result is displayed constant in the main field.
Tests, Long leads mode For a single test the result is displayed constant in the main field. No latest results are displayed in the secondary field unless multiple tests have been made in this sequence. Note: The TICK button ( the secondary fields. ) will clear the previous results in Two previous results appear in the secondary fields, left is the previous result and right is the result before that.
Error and Warning Conditions 8. Error and Warning Conditions If an error code appears on the display follow the on screen instructions. 8.1 Error code categorization Item Number Range Description User Action 1 1 - 999 Non dismissible errors Restart unit to recover. 2 1000 - 1999 User dismissible errors Press 3 2000 - 2999 Auto dismissible errors eg voltage present warning disappears when voltage goes 4 3000 - .... Logged only errors No user intervention 8.
Settings 9. Settings In this section various user settings can be adjusted or accessed. Megger DLR02 icons 9.1 General settings Switch the rotary switch to the settings mode . µΩ mΩ µΩ Go to the general settings tab . Use soft key 2 to select required setting as listed below. General settings Key Press Beep Can be set on or off. Results Beep Can be set on or off. Background Colour Toggle between yellow and white using the tick button.
Settings 9.2 Language settings Switch the rotary switch to the settings mode (Refer to 9.1 General settings on page 28). Go to the language settings tab . Use soft keys 2 and 3 to highlight a language, and press the TICK button ( ) to select the highlighted language. Available languages are English, French, German and Spanish. Changing the set language changes the on screen display language and the keyboard layout. 9.3 Instrument Information Switch the rotary switch to the settings mode (Refer to 9.
Settings 5. When complete, remove the USB flash drive. 6. Restart the DLRO2 (turn off and on). 7. If a measurement firmware update is to be performed, then the measurement firmware update screen will display. At the end of the firmware update, the instrument will automatically restart. 30 DLRO2 www.megger.
Maintenance 10. Maintenance Note: There are no user replaceable parts within the DLRO2. 10.1 General Maintenance Test leads should be checked before use for damage and continuity. Ensure the unit is kept clean and dry after use. Close all covers when not in use. 10.2 Cleaning 1. Disconnect from mains power. 2. Wipe the instrument with a clean cloth dampened with either water or isopropyl alcohol (IPA). 10.
Maintenance 10.3.2 Battery Charging When charging NiMH rechargeable batteries, only use the power supply provided by Megger. Other power supplies will not function with the DLRO2. The Megger power supply is designed to preserve the functions and accuracy of the DLRO2. Warning: ONLY NiHM batteries are rechargeable. When charging the DLRO2 while the instrument is OFF, an animated battery will display across the screen to show charging is taking place.
Maintenance 10.4 Battery Replacement Warning: Remove all test leads before removing the battery cover. Caution: Batteries should not be left in the instrument if remaining unused for an extended period. 1 2 4 3 No. Description Quantity 1 Screw, captive 1 2 Cover, battery 1 3 Battery isolation tab 1 4 Batteries 6 www.megger.
Maintenance 10.4.1 Replace batteries and remove isolation tab The batteries are housed in the lower section of the DLRO2, behind the rotary switch. Looking at the back of the instrument, the lower (battery) cover incorporates a stand and has the replacement cell types written on it. NOTE: If using the DLRO2 for the first time remove and discard the battery isolation tab (3). 1. Remove the test leads and ensure the DLRO2 is switched off. 2.
Specifications 11. Specifications Specification Detail PHYSICAL Dimensions: 228 x 105 x 75 mm (8.98 x 4.1 x 2.95 in) Display: Full LCD colour screen with user configurable backlight. Weight: 905 grams (with batteries) SAFETY AND ELECTRICAL PROTECTION Safety rating CATIII 600 V / CATIV 300 V to EN 61010, IEC 61010-031 : 2015, IEC 61010-030 Safety category rating valid to altitude of 3000 m Live voltage Active live voltage protection to 600 V between any test terminals without blowing a fuse.
Specifications TEST CURRENT OUTPUT Normal resistance test mode Current ranges: 2 A, 1 A, 100 mA, 10 mA and 1 mA Maximum compliance output voltage: 3.24 V (1 A mode) 2.2 V (2 A mode) Current output accuracy: Normal and Inductive mode: ±10 % Long test lead mode: +10 % -0% At all battery conditions except with low battery indication Thermal EMF / Seebeck effect compensation: Yes, average of forward and reverse test current measurements.
Accessories and Equipment 12. Accessories and Equipment 12.1 Included Accessories Item Order No. DLRO2, Ducter Low Resistance Ohmmeter 2 A 1012-280 Test leads: Kelvin clip lead set, CAT III 600 and CAT IV 300 1011-928 Kelvin probe lead set CAT III 600 and CAT IV 300 1011-929 Accessories: 240 V charger power supply 1002-736 Batteries: Six 1.2 V NiMH AA 2000mAHR 1002-735 USB memory stick (with user guide) Hanging hook and strap 1012-068 Soft pouch 1012-063 12.
Calibration, Repair and Warranty 13. Calibration, Repair and Warranty Megger operate fully traceable calibration and repair facilities to make sure your instrument continues to provide the high standard of performance and workmanship that is expected. These facilities are complemented by a worldwide network of approved repair and calibration companies, which offer excellent in-service care for your Megger products.
Decommissioning 14. Decommissioning 14.1 WEEE Directive The crossed out wheeled bin symbol placed on Megger products is a reminder not to dispose of the product at the end of its life with general waste. Megger is registered in the UK as a Producer of Electrical and Electronic Equipment. The Registration No is WEE/ HE0146QT. For further information about disposal of the product consult your local Megger company or distributor or visit your local Megger website. 14.
Notes 15. 40 Notes DLRO2 www.megger.
Local Sales office Megger Limited Archcliffe Road Dover Kent CT17 9EN ENGLAND T. +44 (0)1 304 502101 F. +44 (0)1 304 207342 Manufacturing sites Megger Limited Megger GmbH Megger USA - Valley Forge Archcliffe Road Obere Zeil 2 61440 Valley Forge Corporate Center Dover Oberursel, 2621 Van Buren Avenue Kent GERMANY Norristown CT17 9EN T. +49 06171 92987 0 Pennsylvania, 19403 ENGLAND F. +49 06171 92987 19 USA T. +1 610 676 8500 F. +1 610 676 8610 T. +44 (0)1 304 502101 F.
