Compact and safety-designed digital multimeter for voltage measurement
Voltage detection function

Compact and lightweight design for outstanding ease of use
The small form factor fits in your hand perfectly and is easily stowable, making it convenient to
transport to and from the field and boosting work efficiency.

Use Single AAA alkaline battery only
Since the DT4221 only uses a single AAA alkaline battery that can be easily replaced,
there’s no need to carry a large number of spare batteries with you.

Rear probe connections for superior screen visibility and easy storage
Since this design keeps cords from covering up the screen during measurement, you can read values
at a glance. After use, probes can be stored on the rear of the instrument, facilitating a smooth start to
the next measurement job.

Measure output voltage on the secondary sides of inverters by eliminating harmonic components
Accurately measure the fundamental wave alone by eliminating harmonic components with the
DMM’s low-pass filter function.

True RMS measurement for accurate measurement of even distorted current waveforms
Digital multimeters implement two types of measurement: mean-value measurement and true RMS
measurement. The two methods yield significantly different measurement results for current waveforms,
which are often distorted. For accurate measurement, it is necessary to use an instrument with
true RMS capability.

Designed and manufactured in Japan to ensure high quality and guaranteed with a 3-year warranty 

All development, design, and manufacturing processes for almost all Hioki digital multimeters are
carried out at our Head Office in Nagano Prefecture. Some of the industry’s most advanced
technological capabilities enable us to deliver products of the highest possible quality.

Safe measurement requires use of an instrument that suits the measurement location.

To ensure operators’ ability to use measuring instruments safely, IEC 61010 classifies the locations in
which instruments are used into a series of safety-based measurement categories (ranging from CAT II
to CAT IV). Using an instrument that does not satisfy the required safety level can lead to an electrical
accident. Despite a compact body, the DT4221 can be used to measure voltage at distribution panels.