CM3291 AC Clamp Meter

• TrueRMS measurement
• drop resistant from 1 m height
• guaranteed operating ambient temperature range of -25 to 65 °C
• continuous operation time up to 70 hours

Detailed Product Overview

The CM3291 clamp meter measures AC current in three ranges up to 2000 A using True RMS measurement. This enables accurate current measurements even when the waveform deviates from a pure sine wave, as commonly found in circuits with electronic loads, frequency converters or switching power supplies. 

The clamp accommodates conductors up to 46 mm in diameter and is designed for measurements in densely wired distribution panels where space around the conductor is limited. This allows current measurements on larger installation conductors and supply cables commonly found in electrical installations and power distribution systems.

In addition to AC current measurement, the instrument measures voltage up to 600 V AC/DC and provides resistance measurement and continuity testing. The safety ratings are CAT IV 300 V / CAT III 600 V for both current and voltage measurement. 

Test Leads and Flexible Current Sensor

Voltage, resistance and continuity measurements are performed using the included L9208 test leads. The optional 9209 Test Lead Holder allows one test lead to be fixed to the rear of the instrument during measurements. The L9208 test leads are compatible with the optional HIOKI accessories L4934 for temporary hands free connection to conductors and terminals and L4933 for measurements at closely spaced contact points. 

For measurements on larger conductors, the instrument can be used with the optional CT6280 Flexible Current Sensor. This extends AC current measurements up to 4200 A and enables measurements on large conductors, busbars and cable bundles. 

Transport and Protection

The CM3291 is supplied with a protective hard carrying case that protects the instrument during transport and use in demanding working environments. The instrument also fits into the case when the optional 9209 Test Lead Holder is installed.

Due to its larger clamp jaws, the CM3291 does not fit into the smaller, also separately available HIOKI carrying cases 9398 or C0205, which are intended for clamp meters with smaller clamp openings. When the optional CT6280 Flexible Current Sensor is used together with the CM3291, the larger optional 9812 carrying case is recommended for transporting the instrument and sensor together. 

Designed for Field Use

The instrument is designed for field use and provides drop protection from a height of 1 m. The operating temperature range of −25 °C to 65 °C allows use in outdoor installations and demanding environments. Like all HIOKI clamp meters, the instrument is manufactured in HIOKI’s own production facilities in Japan.