Fluke 1621 GEO Earth Ground Tester

Fluke 1621 GEO Earth Ground Tester

The Fluke 1621 is an easy-to-use earth ground tester for measuring the resistance of earth electrodes and earthing systems. It is the first line of defence in detecting reliable earth connections, and the unit features the two basic ground testing methods most Irish electrical work relies on: 3-pole Fall-of-Potential testing with auxiliary stakes, and 2-pole resistance measurement where a known good earth is already available. Single-button operation, automatic noise voltage detection and a hazardous voltage warning keep routine testing quick and safe.

As an authorised Fluke distributor, Powerpoint Engineering supplies and supports the 1621 for electrical contractors, utility test engineers and earth ground specialists. Its convenient size, rugged holster and large, clear backlit LCD display make it an ideal field earth tester for most work environments. The measuring method follows IEC/EN 61557-5, the standard for earth resistance testing.

What the Fluke 1621 measures

• 3-pole Fall-of-Potential earth ground resistance, the standard method for testing an earth electrode with auxiliary stakes
• 2-pole resistance measurement for quicker checks where a reference earth already exists
• Interference (noise) voltage, with automatic detection that flags any reading affected by stray voltage
• Adjustable limit setting that alerts you the moment a measurement falls outside your pass or fail threshold

Specifications

Where the Fluke 1621 is used

The 1621 suits routine earthing verification rather than specialised substation diagnostics. Typical Irish applications include:

• Commissioning earth electrodes on new commercial and industrial installations
• Periodic maintenance and compliance checks against the ETCI National Rules for Electrical Installations
• Troubleshooting earthing problems where resistance has risen through soil conditions, corrosion or a loose connection
• Checking dedicated earths at remote cabinets, masts and small plant rooms

If you need broader test methods or full substation workflows, the Fluke 1620 Series earth ground testers step up from the 1621 baseline.

What is in the box

• Fluke 1621 tester and protective holster
• Two measuring leads with alligator clips, 2 m
• One 9 V alkaline battery and the user manual

For staked 3-pole testing, the Fluke 1621 Kit adds earth stakes and 25 m and 50 m cable reels, so the unit is ready for field measurement straight away. We can also keep the instrument calibrated through our calibration and repair laboratory, with traceable certificates. Full figures are on the official Fluke 1621 datasheet and across the wider Fluke earth ground testing range.

FAQs

What is the difference between staked and stakeless earth testing?

Staked testing, such as the 3-pole Fall-of-Potential method the 1621 uses, drives auxiliary stakes into the soil to measure an earth electrode in isolation. Stakeless testing uses a clamp to measure earth loop resistance without stakes, which suits multi-earthed systems but needs a different instrument.

What earth resistance range does the Fluke 1621 measure?

It measures from 0.15 Ohm up to 1999 Ohm across three ranges, with resolution down to 0.01 Ohm. That covers the great majority of earth electrode and earthing system checks on Irish commercial and industrial sites.

Is the Fluke 1621 suitable for substation earthing testing?

The 1621 is an entry-level earth electrode tester for basic ground resistance testing. Full substation earthing surveys usually need expanded test methods and a higher 1620 Series model. Speak to our team and we will match the right tester to your procedure.