This document describes the features and characteristics of the digital multimeters M840D/DT890B+/M890C+/M890D/M890F/M890G/DT930F+/M1000, including measurement of DC and AC voltage, current, resistance, diodes, transistors, buzzer continuity, as well as functions such as capacitance, temperature, and frequency.
This manual introduces the M840D handheld digital multimeter, describing its robust construction, LCD display, and measurement capabilities for voltage, current, resistance, capacitance, temperature, frequency, and diode/continuity tests. Safety precautions, battery and fuse replacement, and proper probe handling are also covered.
Detailed sections explain how to select ranges, connect probes, and interpret readings for DC/AC voltage, DC/AC current, resistance, capacitance, temperature, and frequency measurements, along with special functions such as data hold and hFE testing. This manual is written in Chinese.
| Display | LCD, 19 mm character height, max 1999 counts |
|---|---|
| Input impedance | 10 MΩ |
| Measurement speed | ≈2–3 readings per second |
| Frequency response (voltage) | 40 Hz – 400 Hz |
| Battery type | 9 V stacked IEC 6F22 |
| Fuse rating (M840D) | 2 A / 250 V, Φ5 × 20 mm |
Do not exceed 1000 V for DC voltage; higher voltages may damage the instrument.
If the display shows “1”, the range is overloaded; turn the range selector to a higher range before reading the value.
Use a 2 A / 250 V fuse (Φ5 × 20 mm) for the M840D model.