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Clamp meter

The clamp meter supports you in the exact recording of current strength and uses the magnetic field that surrounds the conductor for its indirect measurement of the magnetic field. It is therefore not necessary to disconnect the electric circuit to activate the measuring instrument directly on the cable, because the measurement is contactless.

The current probe – for current strength measurement

The advantages of the clamp meters testo 770

  • Innovative clamp mechanism to grab individual cables without any problem

  • With additional functions for starting current, output and measurement in the μA range

  • Communication with the testo Smart App via Bluetooth

Clamp meter testo 770 in comparison


Clamp meter testo 770 in comparison

Your advantages at a glance

Full retractable pincer arm

Ideal for wires in tight spaces.

Precise clamp multimeters for various applications

The pincer-like iron core allows targeted splitting of the busbars. This operating method enables you to measure the current even where you cannot switch off the system temporarily. Using a clamp multimeter makes it possible to record multiple measurement data. These elements allow flexible use and ensure clear data collection.

When using the clamp multimeter, two important points must be kept in mind:

  • only one single conductor can be grasped and measured,

  • if the clamp encloses an entire cable which contains both conductor and return conductor, only the leakage currents are measured.

The leakage current probe – for even more precision

The leakage current probe is an important measuring instrument for precision work in electronics. In contrast to the classic clamp meter, these diagnostic tools prove to be very sensitive, which means you can also measure extremely small currents with them.

High-quality, precise leakage current probes have additional functions, which for instance also test the starting current and measurement data in the μA range. This typically involves a digital clamp meter which you can above all use in the following areas:

  • continuity and resistance testing,

  • voltage measurement,

  • RMS current measurement.

High-precision clamp meters from Testo – for greater safety

Testo's modern measuring instruments are characterized by an innovative grab mechanism which is easy to operate. The way the mechanism was designed enables it to grasp the individual conductors properly. This means it ensures reliable, contactless measurement of the current values and other relevant data. Even when the power cables are very tightly packed and only have a very small diameter, you can be sure the clamp meter and leakage current probe will work reliably. The clamp multimeter has a two-line display which is easy to read out and Auto-AC/DC. You have the choice between the following three models:

  • testo 770-1 with a fully retractable pincer arm for a high level of flexibility,

  • testo 770-2 with additional temperature adapter and measuring values in the μA range,

  • testo 770-3 with optimized TRMS method and Bluetooth connection.

For the recording of static magnetic fields

In order to be able to measure direct current too, the DC clamp meter carries out a resistance measurement that is dependent on the magnetic field. This enables static magnetic fields to be recorded, which is necessary because there are no alternating fields present with direct current. The magneto-resistive resistances which are required for this are fitted in a gap. Their really weak signal needs to be strengthened electronically, so the measuring instruments are equipped with an appropriate energy storage device and function via electric power or a battery. The DC clamp meters are also suitable for alternating current.

testo Smart App

One App for all applications.

The testo Smart App guides you quickly and easily through measurements on refrigeration, air conditioning and heating systems.

Now new:

PRO measuring programs for increasing the efficiency of your applications

Find out more


Compatible with all Bluetooth-enabled Testo measuring instruments


Direct report dispatch by e-mail


All measurement values at a glance


Intuitive measurement menus


Free download, free use


PRO measuring programs