Extech 4-Wire Earth Ground Resistance Tester Kit

Extech 4-Wire Earth Ground Resistance Tester Kit


The Extech 4-Wire Earth Ground Resistance Tester Kit measures earth ground in 4 ranges from 2 to 2000Ω.


  • 4-wire, 3-wire, and 2-wire testing
  • Automatic I (current) spike check
  • Automatic P (potential) spike check
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The Extech 4-Wire Earth Ground Resistance Tester Kit includes all the hardware necessary to measure earth ground in 4 ranges from 2 to 2000Ω. The kit includes 4-wire, 3-wire, and 2-wire testing. The large dual line LCD displays autoranging, automatic I (current) spike check, and an automatic P (potential) spike check.

Notable Specifications:
  • Earth ground resistance ranges: 2Ω/20Ω/200Ω/2000Ω
  • Basic accuracy: +/-(2%rdg+3d)
  • Resolution: 0.01Ω/0.1Ω/1Ω/0.01kΩ
  • Test current/frequency:< 2mA/820Hz
  • AC earth voltage/frequency: 0 to 300VAC/40 to 500Hz
  • Accuracy: +/-(2%rdg+3d)
  • Power supply: eight 1.5V AA batteries
  • Dimensions: 9.8x7.8x4.3" (250x190x110mm)
  • Weight: 3.15lbs (1430g) (batteries included)
What's Included:
  • (1) Earth ground resistance tester
  • (4) Test leads with alligator clips
  • (4) Auxiliary earth bars
  • (8) 1.5V AA batteries
  • (1) Hard carrying case
Image Part # Product Description Price Stock Order
Extech 4-Wire Earth Ground Resistance Tester Kit GRT300 4-Wire earth ground resistance tester kit
Usually ships in 1-2 weeks
Extech 4-Wire Earth Ground Resistance Tester Kit GRT300-NISTL 4-Wire earth ground resistance tester kit, NISTL traceable
Usually ships in 1-2 weeks

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