General
Inductance measurement range	500 µH
Earth fault current range	40 A
Enclosure diameter	35 mm
Automatic Pre-HOLD mode
Automatic calibration
Real-time clock
Hand guard
Rotary switch with silicone coating
LCD display
HOLD key

The earth continuity clamp CA 6416 from Chauvin Arnoux is a specialised measuring instrument for determining loop resistances in earthing systems. It is designed for use in electrical installations up to 600 V CAT IV and serves for professional testing of earth loops as part of electrical safety. The device is delivered in a transport case, ensuring protection and ease of transport. The clamp enables simultaneous display of impedance and fault current, touch voltage, as well as the resistive and inductive components of the measured earthing impedance. The measured values can be converted to the mains frequency to minimise measurement errors at low resistances.

Applications

The CA 6416 is designed for use in electrical installations within low-voltage technology, particularly in buildings, industrial plants, and for the maintenance of safety measures. It is used to test the effectiveness of earth loops, which serve as return paths for fault currents in the event of a fault in the electrical system. Measuring touch voltage allows an assessment of the risk to personnel in case of a fault. The clamp is suitable for indoor use, as the protection rating IP 40 does not provide protection against water or dust.

Functions and Equipment in Detail

A central feature of the CA 6416 is the force-compensation system, which allows the clamp to be opened and held with minimal muscle effort. This reduces user strain during prolonged measurement procedures. The display is based on LCD technology with high contrast and sharpness, ensuring readability from an angle of nearly 180° under various lighting conditions. The display can be operated in standard mode or extended mode, with up to three measurement values displayed simultaneously in extended mode. The clamp features an automatic Pre-HOLD mode, which already displays ongoing measurements as soon as the clamp is opened, increasing measurement speed.

Technology Explained Simply

The earth continuity clamp measures the impedance of the earth loop, which consists of resistance and inductance. The impedance is converted to the mains frequency to improve measurement accuracy at low resistances. Touch voltage is calculated by multiplying the loop impedance by the fault current. This value is compared to a set threshold, and if exceeded, a visual alarm (flashing symbol and threshold display) and an audible warning buzzer are triggered. The clamp performs an automatic air gap calibration at start-up to minimise measurement errors. Measurement values can be stored using a HOLD button.

Compatibility and Accessories

The CA 6416 is compatible with the evaluation and protocol software DataView, enabling detailed analysis of measurement results. Additionally, a Bluetooth / USB modem for PC is available, enabling data transfer from the clamp to the computer. A calibration loop CL1 can be used to validate measurement accuracy. The clamp is designed for use with a rotary switch, which is operable even with protective gloves thanks to a silicone coating.

Mounting and Installation

The clamp is closed around the conductor to be tested, with contact surfaces kept smooth and clean to avoid measurement interference. The centring parts ensure optimal alignment of the two measurement head halves, enabling accurate measurements over time. The clamp is not intended for use in explosive environments. Measurement is performed without additional mounting or installation — the clamp is simply placed around the conductor.

Operational Advantages

The CA 6416 offers high measurement accuracy through impedance conversion to the mains frequency and automatic calibration. The integrated touch voltage display with alarm function increases user safety. The memory function for up to 2000 measurements with timestamp enables detailed documentation. The ergonomic design with force compensation and large control buttons facilitates daily use. The clamp is robust and designed for professional use.

Protection Rating and Safety

The clamp is designed for use in electrical installations up to 600 V CAT IV, representing a high safety level for measurements in low-voltage installations. The protection rating IP 40 protects against contact with tools and splashing water, but not against dust or immersion. The clamp is not suitable for outdoor use or in damp environments. The warning function for hazardous voltages increases safety during measurement.

Measurement Ranges and Memory

The clamp features large measurement ranges: up to 1500 Ω for resistance, 500 µH for inductance, and 40 A for fault current. Measurement values can be stored with a real-time clock timestamp. The memory capacity is up to 2000 measurements. The clamp features programmable alarms for resistance, current, and voltage, which can be individually set. A warning buzzer signals the alarm, and the clamp automatically powers off to save energy.

Ergonomics and Operation

The clamp is equipped with a hand guard to prevent hands from slipping during measurement. The rotary switch has a silicone coating to allow operation even with protective gloves. The control buttons are large and provide direct access to functions. The display is bright and clear, readable even in direct sunlight. The clamp is easy to handle and suitable for daily use in electrical trades. Batteries are not included in the delivery scope.