TECHNICAL BULLETIN TB-3055 Low Resistance Tester Operation and Maintenance Made in the United States of America ANSI/ESD S6.1 Grounding 6.4.1 The resistance of the conductor from the groundable point ground of any ESD technical element (e.g. worksurface, floor, chair, wrist strap, etc.) to the common point ground or common connection point shall not be greater than 1 ohm. Where a resistor is used in the grounding conductor, the total resistance shall include the value of the resistor. 6.4.2 The resistance of the conductor from the common point ground to the AC equipment ground shall not be greater than 1 ohm. Packaging 1 Low Resistance Tester 1 Threaded Banana Plug 1 Threaded Needle Point 1 Alligator Clip 1 Banana Jack Outlet Adapter 1 Certificate of Calibration Features and Components Figure 1. Desco 19245 Low Resistance Tester A B C D E F G Description Descos Low Resistance Tester is designed to measures resistance of grounding paths of banana jacks and other equipment. Selectable Test Ranges: <1 ohm, <2 ohms and <20 ohms allow the operator to test grounding conductors per ANSI/ESD S6.1 Grounding and ESD TR20.20. The Tester is equipped with pass/fail (go/no go) audio and visual indicators that activate to confirm that the grounding conductor being tested meets the test range. The low battery indicator lets the operator know when battery needs to be replaced. ESD Handbook ESD TR20.20 section 5.5.2.2 Electrical Hand Tools All electrical tools and equipment used to process ESD sensitive devices require the three prong, grounded-type AC plug. The metal portions of the tool that touch the device should have a low resistance (<2 ohms) to the equipment ground terminal on the plug. In some cases, the user may wish to verify that the metal portions of the tool have Figure 2. Low Resistance Tester features and acceptable voltage levels and leakage current. The tester components defined in ESD STM13.1 provides a means of checking soldering iron tips while being used. Although the document A. Selectable Test Ranges: Select the appropriate range was written to make measurements on soldering and for required test <1 OHM, <2 OHMs, and <20 OHMs. desoldering equipment, the measurement techniques can be used for other electrical hand tools. The working part of AC B. Test Button: Press and hold button to activate the tester. powered tools should be capable of providing a conductive C. Threaded Banana Plug/Needle Point: Standard Kit path to ground. New powered hand tools such as soldering includes a banana plug and needle point adaptor. irons typically should have a tip to ground resistance of less than 1.0 ohm. D. Audio and Visual Test Indicators: LED and buzzer Pass NOTE: This resistance may increase with use but should be result. less than 20.0 ohms for verification purposes. DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 (909) 627-8178 Fax (909) 627-7449 DESCO EAST - One Colgate Way, Canton, MA 02021-1407 (781) 821-8370 Fax (781) 575-0172 Website: Desco.com 2012 DESCO INDUSTRIES, INC. TB-3055 Page 1 of 4 December 2012 Employee OwnedE. Low Battery LED: LED illuminates when the battery needs to be replaced. F. 6 Foot Coiled Cord: Insulation black color PVC G. Banana Plug: Industrial Standard .175 (4.4 mm) Banana Plug, fits banana jack .157 . Operation USING THE TESTER 1. Use the slide switch to select a test range. 2. Connect the coil cord banana plug end to known ground. Use adapters where needed. NOTE: The Desco Low Resistance Tester may be used with an outlet polarity checker such as the Desco 19219 to determine a known ground. 3. Connect or touch the tester end to a banana jack or other equipment that is being tested for resistance to ground. 4. Press and hold the test button. 5. An audio and visual indication will activate for a PASS Figure 5. Testing auxiliary ground with the 19245 tester condition. 6. A FAIL condition is indicated when the buzzer does not Example of Test Range Uses sound and the PASS does not illuminate. <1 OHM Range - ESD Technical element Grounding Conductors: Banana Jacks, Grounding Blocks, Mat Ground Cords ANSI/ESD S6.1 Grounding, sections 6.4 Technical Elements, 6.4.1, 6.4.2 and 6.4.3 - New AC Powered Hand Tools ESD Handbook ESD TR20.20 section 5.5.2.2 Electrical Hand Tools <2 OHM - Soldering Irons ESD Handbook ESD TR20.20 section 5.5.2.2 Electrical Hand Tools - Other AC Powered Hand Tools ESD Handbook ESD TR20.20 section 5.5.2.2 Electrical Hand Tools Figure 3. Testing ground points with the 19245 tester <20 OHM - Soldering iron verification ESD Handbook ESD TR20.20 section 5.5.2.2 Electrical Hand Tools - Auxiliary grounds (ground rods) ANSI/ESD S20.20* * ANSI/ESD S20.20 requires <25 ohms from the Auxiliary Ground to the Equipment Grounding Conductor. Descos Low Resistance Tester only tests to <20 ohms. In cases of a no pass result with the Low Resistance Tester when testing an Auxiliary Ground, an Ohm meter should used to determine the actual resistance from the Auxiliary Ground to the Equipment Grounding Conductor Figure 4. Testing a soldering iron with the 19245 tester DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 (909) 627-8178 Fax (909) 627-7449 DESCO EAST - One Colgate Way, Canton, MA 02021-1407 (781) 821-8370 Fax (781) 575-0172 Website: Desco.com 2012 DESCO INDUSTRIES, INC. TB-3055 Page 2 of 4 Employee Owned