DT4281 - High Accuracy Digital Multimeter with Current Clamp Support

Key Specifications

• 0.025% basic DC accuracy 
• True RMS and 60000 count display
•  Multi range current clamp support 
• AC/DC voltage up to 1000 V 
• CAT III 1000 V, CAT IV 600 V 

Typical Applications

• AC current measurement with optional current clamps
• Troubleshooting in control cabinets and power distribution systems 
• Maintenance and commissioning in field service 
• Electrical measurements on industrial equipment 
• Temperature measurement with thermocouple support

Detailed Product Overview  

The HIOKI DT4281 is a battery powered high accuracy digital multimeter with 0.025% basic DC accuracy and a 60000 count display for service, maintenance and commissioning. The high accuracy enables precise detection of small voltage deviations. Compatible HIOKI current clamps display AC current directly as a current value on the instrument without manual conversion of the clamp output signal. This supports faster current checks and troubleshooting in electrical systems and industrial installations. 

Voltage, Current and Input Safety 

The instrument measures DC, AC and AC+DC voltage up to 1000 V and meets CAT III 1000 V and CAT IV 600 V safety ratings. For direct AC/DC current measurement, it provides the ranges 600 μA, 6 mA, 60 mA and 600 mA, while compatible HIOKI current sensors extend AC current measurement from 10 A to 1000 A. Terminal shutters linked to the rotary switch block unused input terminals and help prevent incorrect test lead insertion. 

During AC voltage and AC current measurement, the instrument displays frequency simultaneously as a secondary reading. The frequency measurement range extends from 99.999 Hz to 500.00 kHz with an accuracy of ±0.005% of reading + 3 digits. Additional measurement functions include resistance, continuity, diode test, capacitance and temperature measurement with a K thermocouple such as the optional DT4910. 

Current Measurement with Current Sensors 

For AC current measurement beyond the direct input range, the DT4281 supports compatible HIOKI current sensors. The sensors are connected via the 9704 BNC adapter. When the current range selected on the instrument matches the range selected on the connected sensor, the measured value is displayed directly as a current value on the instrument. Manual conversion of the sensor output signal is not required. 

With the compatible 9010-50, 9018-50 and 9132-50 current sensors, the instrument covers AC current measurement from 10 A to 1000 A. The 9010-50 and 9018-50 support ranges up to 500 A, while the 9132-50 extends the range up to 1000 A. For applications up to 500 A, the 9010-50 covers current measurement up to 1 kHz, while the 9018-50 extends the frequency range up to 3 kHz and provides higher amplitude and phase accuracy. 

For Service, Maintenance and Process Signals 

The DT4281 covers AC voltage measurements from 20 Hz to 100 kHz. In addition, the analog low pass filter with a 630 Hz cut off suppresses higher frequency components so that the fundamental waveform can be evaluated more clearly. For service and maintenance tasks, the instrument also provides MAX/MIN and peak value measurement as well as HOLD and AUTO HOLD functions. The relative display function shows subsequent readings relative to a reference value, and zero adjustment compensates offsets before measurement, for example when low resistance values are evaluated. Excessively high input is indicated by the red screen backlight and a buzzer.

For process related measurements, 4 to 20 mA and 0 to 20 mA signals can be displayed directly as percentage values from 0 to 100%, which is useful for checking transmitter and process signals without manual conversion from mA values. Measured values can be stored in the internal memory with up to 400 data points and transferred to a PC with the optional DT4900-01 Communication Package. 

For Everyday Use in Service and in the Field 

The DT4281 is built for everyday use in service, maintenance and commissioning, with an operating temperature range from -15 °C to 55 °C, drop resistance from a height of 1 m and a continuous operating time of approximately 100 hours with four AA alkaline batteries. The rear kickstand supports setup at the measurement location, while the test leads can be stored directly on the back of the instrument. The supplied L9300 test lead uses a movable finger guard instead of separate protective caps. This allows adaptation of the exposed metal tip length to the relevant measurement category without loose accessories that can be misplaced during daily work. 

For mounting at the measurement location, the DT4281 can be combined with optional magnetic straps. The Z5004 is sufficient for typical attachment to magnetic steel surfaces such as distribution cabinets. Where additional cable weight is present, especially with connected current clamps, the stronger Z5020 provides a higher holding force and greater stability if the instrument or connected leads are bumped or shifted during work. Like all HIOKI digital multimeters, the DT4281 is developed in Japan and manufactured at HIOKI’s own production facilities in Japan.