Eigenschaften
Continuity with buzzer, test current	≤ 1 mA
Continuity with buzzer, frequency	-
Dimensions / weight	163 x 64 x 40 mm / 210 g

The two-pole voltage tester C.A 742 from Chauvin Arnoux is a standard-compliant measuring instrument for verifying de-energisation before working on electrical installations. It serves as a reliable tool for electricians to ensure safety during maintenance and repair work. The device detects voltages in the range of 12 V to 690 V AC (16 2/3 Hz to 800 Hz) as well as 12 V to 750 V DC. Voltage detection is indicated via an LED display, which automatically shows the voltage type (AC/DC) and provides polarity indication. A redundant safety system with a red ELV-LED (Extra Low Voltage) ensures that a warning indication is activated when voltages exceed 50 V AC or 120 V DC, with the LED flashing frequency increasing as voltage rises.

Applications

The voltage tester is designed for use in installation category CAT IV 600 V and is suitable for work on electrical installations indoors and outdoors. It is particularly used before working on power distribution networks to confirm actual de-energisation, as required by standards EN 50110-1 and VDE 0105-1. The IP65 protection rating allows use in harsh environments, including outdoors, at temperatures from -15 °C to +45 °C and relative humidity from 20 to 95 %. The removable test probes and test leads allow flexible adaptation to different application scenarios.

Functions and Equipment in Detail

The device features single-phase line conductor detection, enabling identification of the line conductor (phase) with contact using only one test probe. A rotating field direction indicator up to 400 Hz allows quick and easy determination of rotation direction in three-phase systems, with indication L1-L2-L3 or L1-L3-L2 regardless of labels such as left- or right-rotating field. Continuity testing is activated by pressing the Ω button and indicates with optical and acoustic signals when resistance is below 100 Ω (typical, max. 150 Ω). The test current is ≤ 1 mA, the open-circuit voltage is ≤ 3.3 V, and the protection rating is up to 1000 V.

Technology Explained Simply

The C.A 742 is equipped with a complete self-test that checks internal circuits, power supply, displays, and the condition of test leads. This ensures the device is functional before each measurement. Power supply is via two 1.5 V batteries (LR03), enabling 7500 measurements of 10 seconds each. The device impedance exceeds 300 kΩ, and the maximum current is 3.5 mA RMS. Frequency ranges include DC and 16 2/3 to 800 Hz for AC. Test probes are optionally available with IP2X protection, which is required in certain countries and provides additional operator safety.

Compatibility and Accessories

Various accessories are compatible with the voltage tester, including red and black test probes with 2 mm Ø, test leads with IP2X test probes, protective caps for test probes, and adapters such as the C.A 753 for quick testing at Schuko sockets. The test leads are fitted with 4 mm angled connectors (female), with lengths of 0.25 m (black) and 0.85 m (red). An accessory set includes a connecting cable (1.10 m) and a set of IP2X test probes (red/black). A carrying case (120 x 200 x 60 mm) and a wrist loop are also available.

Mounting and Installation

Mounting is done by simply connecting the removable test leads to the test probes. The test probes are fitted with springs that generate a contact force of 10 N, ensuring reliable measurement even when personal protective equipment (PPE) is used. Device dimensions are 163 x 64 x 40 mm, and weight is 210 g. Operation is via buttons and displays on the device, with functions such as voltage detection, phase identification, and continuity testing directly accessible through the user interface.

Operational Advantages

The C.A 742 offers high reliability through the integrated self-test and redundant safety system. The removable components allow easy maintenance and adaptation to different requirements. The IP65 protection rating ensures safe use in harsh environments, and the CAT IV 600 V classification makes the device suitable for work on high-voltage installations. The combination of visual and acoustic indication (buzzer) for voltage detection and continuity testing supports quick and safe decision-making during operation. Compliance with IEC 61243-3 Edition 3 and DIN VDE 0682-401 ensures adherence to legal and technical requirements. Batteries are not included in the delivery scope.