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Inst ruments and Meters – 2450
Phone: 573-682-5521 Email: hpsliterature@hubbell.com Web: hubbellpowersystems.com
Page 2473
November 2012
Self-Contained, Portable Convenience
• Used to check resistance in protective grounding sets
• 120 VAC and 230 VAC models available
• Applies Direct Current across the test specimen
• Seven-minute video, included with each unit, shows
how to use tester
• Instruction manual includes procedure details
• All components store in tester’s integral carrying case
Protective-Grounding-Set Tester
• Meets ASTM Standard F 2249
• Offers easy, accurate diagnostics
Troubleshooting Mode
• If a ground set does not pass initial test, Tester can help
isolate problems
• High-resistance source can often be remedied by
simple repairs to cable set
• Retesting then can quickly verify the effects of repairs
• For troubleshooting mode, test probes are furnished to
plug into the Tester
• A switch activates them instead of ball-stud terminals
• Probes are used to test across each contact interface in
ground set
• Results display in milliohms, just as in the first test
mode
Optional Terminals For Special Ground
Sets
• Standard ball-stud terminals accept most types of
ground clamps, including Chance ball-socket clamps.
• To test special-application grounding sets for
underground-distribution transformers or switchgear,
two optional adapters shown are available as separate
items
Simple, One-Button Testing
• Digital display shows the resistance measured in
milliohm
• This is compared with a preset threshold for the size
grounding cable selected (#2, 1/0, 2/0 or 4/0)
• Green “Pass” or red “Fail” light also indicates test
results
• Factory preset at 100 Volts
• User can easily change the Tester’s basis for voltage
allowed
• Adjusting this limit automatically causes a
corresponding shift in resistance thresholds for all
grounding cable sizes
• Regardless of the voltage-allowed setting or cable
size selected, the Tester displays resistance of each
specimen in milliohms
• Resistance displayed with ±1% accuracy, from 1 micro-
ohm to 6.5 ohms
• Utility must establish maximum resistance allowed for
protective grounding sets used on each specific area of
systems
• How the utility calculates these values depends on
several factors outlined in the Tester instructions
• Sample calculations with reference tables and charts
are in manual