Hioki FT6041 Earth Tester with 4-Pole and Clamp Methods

A multi-method earth tester for pole, clamp and low-resistance measurements

The Hioki FT6041 is a multi-method earth tester: one instrument that measures earth resistance by four-pole, three-pole and two-pole methods, by a clamp-assisted method (MEC) and by a two-clamp method, and also measures low resistance by four-terminal and two-terminal methods and ground potential. Because the same tester covers several methods, the technician can pick the one the site allows: classic spikes where electrodes are separate, clamp methods where the earth cannot be disconnected, and two-clamp measurement for pylons and multi-earth systems.

Measurements run in auto-range from 3 ohm to 300 kohm (display from 0.000 ohm to 300.0 kohm), with 0.001 ohm resolution on the lowest range. The test frequency can be switched among 55, 94, 105, 111 and 128 Hz to avoid interference, the output voltage can be switched between 30 V and 20 V rms for four- and three-pole work, and operation uncertainty to EN 61557-5 is stated as +/-30 % of reading over a guaranteed range of 5.00 ohm to 300.0 kohm. The enclosure is rated IP65/IP67 with the protector and terminal covers in place, and the tester survives a 1 m drop onto concrete when covered by the protector (not with NiMH batteries inserted).

Technical specifications

Standard package and the FT6041-91 set

The package lists the FT6041 with protector, two L9840 auxiliary earthing rods, a 4 m measurement cable L9841, a 25 m yellow cable (L9845-31) and a 25 m blue cable (L9845-33) with winders, a 50 m red cable (L9845-52) with winder, two L9846 earth nets modules, test lead L9787 for two-pole work, carrying cases C0208 and C0209, four LR6 batteries and the manual. The FT6041-91 set adds the FT9847 signal induction clamp, a 25 ohm operation-check resistor and the CT9848 clamp-on sensor needed for the two-clamp and MEC methods. The Wireless Adapter Z3210 and the pin-type lead 9772 for four-terminal low-resistance measurement are options.

Two-clamp measurement is useful where an earth electrode is part of a closed loop and cannot be disconnected: one clamp injects the signal and the other senses the current, so no spikes are required. Choose the FT6041-91 set whenever clamp methods are in scope.

What to confirm before ordering

Decide whether clamp methods are needed, which determines whether the FT6041-91 set or the base FT6041 is ordered. Confirm the cable lengths for your site (25 m and 50 m are included in the package) and the earthing standard being tested. For simpler jobs the FT6031-50 is a three-range spike tester, and for multi-grounded systems the FT6380-50 clamps on the earth conductor.

How the Hioki FT6041 works

The tester sends a test current through the earth under test and a set of auxiliary spikes. It measures the voltage that results and shows the resistance. In the clamp methods, clamps around the earth wire take the place of some of the spikes.

Where the FT6041 is used

• Substation earths
• Building earths
• Pylon and pole earths
• Multi-earth systems
• Low resistance checks

Selection checklist for the FT6041

• Earth method needed
• Spike space on site
• Clamp access
• Resistance range
• Interference frequency
• Test voltage
• Lead and clamp accessories
• Battery type

Installation, commissioning and maintenance notes for the FT6041

Set the spikes in a straight line at the spacing in the manual and connect the leads. Pick the method and the test frequency, then read the value. Check the leads and the clamp sensors at regular intervals.

Requesting a quotation for the Hioki FT6041

Please send the earth type, the methods needed and the accessories wanted. Seven Star LLC serves industrial customers in Oman and the GCC and replies with a quotation based on the information provided.

FT6041 tester type

It is a multi-method earth tester.

FT6041 maker

It is made by Hioki.

FT6041 pole methods

It measures earth resistance by four-pole, three-pole and two-pole methods.

FT6041 clamp method

A clamp-assisted method is included.

FT6041 two-clamp method

A two-clamp method suits pylons and multi-earth systems.

FT6041 low resistance

It also measures low resistance by four-terminal and two-terminal methods.

FT6041 ground potential

It measures ground potential as well.

FT6041 range selection

Measurement runs in auto-range.

FT6041 lowest range

The lowest range is 3 ohm with 0.001 ohm resolution.

FT6041 highest range

The highest range is 300 kohm.

FT6041 range steps

The steps are 3 ohm, 30 ohm, 300 ohm, 3000 ohm, 30 kohm and 300 kohm.

FT6041 test frequency

The test frequency switches among 55, 94, 105, 111 and 128 Hz.

FT6041 interference

Changing the frequency helps avoid interference.

FT6041 test voltage

The test voltage switches between 30 V and 20 V rms.

FT6041 test current

The test current is up to 25 mA.

FT6041 two-pole voltage

Two-pole tests use 8 V or 20 V rms.

FT6041 four-pole time

A four-pole measurement takes up to 9 s.

FT6041 three-pole time

A three-pole measurement takes up to 6 s.

FT6041 two-pole time

A two-pole measurement takes up to 3 s.

FT6041 drop resistance

The tester survives a 1 m drop onto concrete with the protector fitted.

FT6041 protector

The protector and the terminal covers shield the tester on site.

Tester records for the FT6041

Record the site, the method used and the date of each test.

Choosing the right FT6041 method

Choose spikes where the earth can be separated and clamps where it cannot.

Documents and quotation

The attached Hioki document is the Earth Tester series catalog in English, which covers the FT6041 together with the other earth testers. A comparable instrument category is represented by the Megger DET4T2 four-terminal earth ground resistance tester; browse the portable test and measurement category for more. Send the order code and quantity for a quotation from Seven Star LLC.