A ground is a crucial component in any electrical system. It routes electricity to the Earth when electrical insulation fails. Ultimately, it provides a definitive path in theses instances and prevents the electrical path from including anyone or anything else. Additionally, enclosures for electrical apparatus as well as radial conductors for cabling are often grounded in order to provide shielding from electrical noise or radiated interference.
Technicians perform Earth resistance testing to ensure ground rods and/or grounding systems are well bonded and provide a low resistance path to ground. The resistance of the grounding system to the Earth may be affected by factors like the resistivity of the soil itself, damaged or partially uprooted stake, as well as corroded connections and broken ground leads.
One of the fastest and most convenient methods of measuring ground resistance is by using the clamp method. Instead of using multiple leads or poles, the device has a jaw that can be clamped around the ground rod. The device then gives you the resistance reading in a few seconds. This method saves you from a lot of time and makes diagnostics faster.
To help you on ground resistance measurement, you might want to check out meters from Megger Test Equipment. The Megger DET24C Ground Resistance Tester is a clamp-on device that has a smooth jaw design and a large diameter that can accept grounding rods or cables with a diameter of 37 millimeters. Another great feature of this device is its built-in EMI suppression circuitry. This feature lets you accurately measure ground resistance even in environments with a high amount of electrical noise.
This Megger tester is an improved version of the DET14C model. However, it has more internal storage so you can save more results. It also has an bluetooth interface that lets you interface with a computer for data transfer, analysis and report generation.
- Elliptical smooth clamp design
- Maximum current at 200 A RMS for 60 seconds and 100 A RMS continuous 50 or 60 Hertz
- Rated CAT IV 600V
- Can measure resistance from 0.05 Ω up to 1500 Ω
- 4+6 backlit LCD readout
- Internal EMI suppression circuit for excellent accuracy
- Measures current from 0. mA up to 35 A
- Has 2 alarm threshold types
- Excellent accuracy whether at 50 or 60 Hertz
- Won’t accumulate dirt in jaws
- Audio-visual alerts for current and resistance limits
- Internal storage for 2000 records
- Automated selection of range
- True RMS measurements up to a 5.0 crest factor
- Jaw measures 9mm x 55mm
- IP 30 rating
- Complies with the Class B, IEC 61326 EMC and BSEN 61326 standards
Related electrical test equipment available for rent from Protec:
Wherever the job takes you (and the equipment), with Protec’s multiple locations, we always ship from the office closest to your desired drop location (if the electrical test equipment you need is in-stock at that location), and the equipment can be returned to the nearest office.
We always consider ALL shipping options in order to save you the most time and money.
Also, if you happen to be close to one of our many office locations, walk-ins are always welcome!
Rely on the Electrical Test Equipment Rental Experts, we are there when and where you need us.
Editor’s Note: This post was originally published August, 2012 and has been updated freshness, accuracy and comprehensiveness.