AC/DC CLAMP METER CM4371-50

True RMS 600 A AC/DC Clamp Meter for the Toughest Situations
With DMM Functions that Deliver Top Safety

Hioki clamp meters are best-in-class measuring devices incorporating Hioki’s expertise in current sensing technology. Model CM4371-50 is a 600 A True RMS clamp meter that features stronger jaws, IP54 dustproof and waterproof enclosure to enable professionals to work quickly in tough situations including the development, repair, and maintenance of equipment and devices such as electric vehicles. Additionally, the high-voltage DC measurement capability of up to 2000 V (*1) is ideal for the clamp maintenance inspections of electrical and solar power equipment.

CM4370 Series Clamp Meters Product Video

Key Features

  • Multiple measurement functions
  • Automatic AC/DC function helps boost work efficiency
  • Measure DC voltages of up to 1700 V (*1) for open voltage inspections of solar panels
  • Simultaneously measure inrush current in RMS and crest values
  • Expanded -25 °C to 65 °C operating temperature range
  • IP54 dustproof and waterproof enclosure
    Jaws (current sensor portion): IP50
  • *1:Your instrument can be used to measure voltages in excess of 1000 V DC if and only if both of the following conditions are satisfied:
  • 1. The circuit under measurement is isolated from the commercial power grid.
  • 2. The circuit under measurement is isolated from ground.
  • e.g.: When measuring the no-load voltage of an ungrounded PV panel
  • Do not use the instrument with circuits whose terminal-to-ground voltage exceeds 1000V. Doing so may result in electric shock.

Model No. (Order Code)

CM4371-50 Wireless Adapter Z3210 not included
CM4371-90 Bundled with the Wireless Adapter Z3210

Data can be downloaded to tablets and smartphones using Hioki’s dedicated free app "GENNECT Cross," available from the Google Play or App Store.

Safe inspection of solar installations with high voltage

DC High V Probe Mode

- Enables high voltage measurement up to CAT III 2000 V
- Safely measure solar installations like the mega-solar without interrupting the grid by simply connecting the DC High Voltage Probe P2000 to compatible Hioki clamp meters and digital multimeters (DMMs)

See details about DC High Voltage Probe P2000

Wireless communication capability for even greater convenience

Wireless support

When the Wireless Adapter Z3210 is installed, Bluetooth® wireless communication is enabled. It transfers measurements to your smartphone or tablet and allows you to quickly create reports with field photos and drawings.

See details about Wireless Adapter Z3210

Excel® Direct Input Function (*1)

Boost work efficiency in the field by letting you directly transfer measurement data to (i.e., enter measured values directly into) templates created as Excel®.

  • *1:The optional Wireless Adapter Z3210 is required.

Helping personnel analyze issues in the field

Harmonic measurement

When combined with GENNECT Cross (*2), you can perform simple harmonic analysis. Applications include problem analysis of power supply systems.

See here for details about GENNECT Cross

Problems that can be caused by harmonics

  • Equipment burn-out and destruction due to overheating
  • Malfunctions of power control devices
  • Increased loss along with reduced service life and efficiency for power devices
  • *2:GENNECT Cross is an free app that lets you connect field measuring instruments to smartphones and tablets using Bluetooth® communications. Wireless Adapter Z3210 (sold separately) is required in order to pair the instrument with GENNECT Cross.

Convenient for repeated measurement and recording tasks!

Automatic hold function

In addition to being convenient when the display cannot be seen during measurement, when the measurement value is stabilized, the display value is automatically held until the next measurement, which is very convenient for repeated measurement and recording tasks.

Assess transient currents at motor startup

The clamp meters can simultaneously measure inrush current in RMS as well as maximum crest values at motor startup and for welding currents.
The clamp meters automatically detect the duration of the inrush current (which can range from several dozen milliseconds to several hundred milliseconds) and measure the current during that interval, enabling them to yield more accurate
measurements than standard clamp-on meters whose measurement interval is fixed to 100 ms.

Assess transient currents at motor startup

Stop worrying about losing test lead caps

Test Lead L9300 incorporate integrated caps for greater convenience and safety. The design lets you change the measurement category simply by sliding the test lead’s protective finger guard. You no longer have to worry about losing caps!

Basic specifications

Accuracy guaranteed: 1 year
DC Current range 20.00 A/600.0 A, Basic accuracy: ±1.3% rdg. ±0.08 A (20 A range)
AC Current range 20.00 A/600.0 A (10 Hz to 1 kHz, True RMS), Basic accuracy: ±1.3% rdg. ±0.08 A (at 20 A)
Crest factor 20.00 A range: 7.5
600.0 A range: 3 or less
DC+AC Current range 20.00 A/600.0 A (10 Hz to 1 kHz, True RMS), Basic accuracy DC, 45-66 Hz: ±1.3% rdg. ±0.13 A (at 20 A)
DC Voltage range 600.0 mV to 1700 V (*1), 5 ranges, Basic accuracy: ±0.5% rdg. ±0.5 mV (at 600 mV)
AC Voltage range 6.000 V to 1000 V, 4 ranges (15 Hz to 1 kHz, True RMS), Basic accuracy 45 - 66 Hz: ±0.9% rdg. ±0.013 V (at 6 V)
DC+AC Voltage range 6.000 V to 1000 V, 4 ranges, Basic accuracy DC, 45 - 66 Hz: ±1.0% rdg. ±0.023 V (at 6 V)
Resistance range 600.0 Ω to 600.0 kΩ, 4 ranges, Basic accuracy: ±0.7% rdg. ±0.5 Ω (at 600 Ω)
Capacitance range 1.000 μF to 1000 μF, 4 ranges, Basic accuracy: ±1.9% rdg. ±0.005 μF (at 1 μF)
Frequency range 9.999 Hz to 999.9 Hz, 3 ranges, Basic accuracy: ±0.1% rdg. ±0.003 Hz (at 9.999 Hz)
Temperature (K) -40.0 to 400.0 ˚C, add temperature probe accuracy to basic accuracy of ±0.5% rdg. ±3.0 ˚C
Voltage detection Hi: 40 V to 600 V AC, Lo: 80 V to 600 V AC, 50/60 Hz
Other functions Automatic AC/DC detection, Plus/Minus judgement function of DC A, DC V, Max/Min/Average/PEAK MAX/ PEAK MIN value display, Filter function, Display value hold, Auto hold, Back light, Auto-power save, Buzzer sounds, Zero-adjustment
Dustproof, waterproof Grip: IP54 (when measuring an insulated conductor only), Jaw (the current sensor portion of the instrument)/ barrier: IP50 *Risk of electric shock from the conductor being measured increases when wet.
Power supply LR03 Alkaline battery ×2, Continuous use 45 hr (Backlight OFF)
Core jaw diameter φ33 mm (1.30 in), Jaw dimension: 69 mm (2.72 in) W× 14 mm (0.55 in) D
Dimensions and mass 65 mm (2.56 in) W × 215 mm (8.46 in) H × 35 mm (1.38 in) D mm, 340 g (12.0 oz)
Included accessories TEST LEAD L9207-10, CARRYING CASE C0203, LR03 Alkaline battery ×2, Instruction Manual×1

Test leads (2)

L9207-10 is a bundled accessory

Options for Test leads (for the L9207-10, L9300) (2)

Attach L9207-10 with the cap removed.
Slide the guard of L9300 and attach as measurement category II.

Options for Test leads (for the L4930) (10)

Test Pin Set L4932 is required when using the Small Alligator Clip Set L4934

Temperature measurement (1)

Other options (1)

Bundled accessory


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