GD128 Smart Digital Multimeter – 9999 Counts True RMS Auto Range, AC 750V / DC 1000V, 9.99A, NCV/Live Test, Capacitance, Frequency, Duty, REL, MAX/MIN/AVG
GD128 Smart True RMS Digital Multimeter — 9999 Count Auto/Manual Range Tester
The GD128 is a smart auto-range digital multimeter designed for professional troubleshooting, electronics diagnostics, and advanced home electrical work. It features a 9999-count VA color display with analog bargraph and input jack LED indication to reduce connection errors during measurement.
True RMS capability ensures accurate AC readings in real-world signals, while automatic identification of common measurement types speeds up workflow. The meter combines broad measurement coverage with practical utilities such as REL comparison mode, MAX/MIN/AVG tracking, NCV detection, and audible alerts for safer diagnostics.
Powered by standard AAA batteries and built to CAT III / CAT IV safety ratings, the GD128 provides versatile portable testing for technicians, installers, and serious DIY users.
Clear readings with bargraph and jack indication LEDs.
Accurate AC measurement in non-linear signals.
Automatic detection of voltage, resistance and continuity.
REL, MAX/MIN/AVG, NCV detection, flashlight and alerts.
Specifications
| Parameter | Value |
|---|---|
| Model | GD128 |
| Display | 9999 counts, VA color digital display + bargraph |
| Ranging | Auto range + manual range |
| Sampling rate | ~3 times per second |
| Operating temperature | 0–40 °C |
| Dimensions | 83 × 23 × 165 mm |
| Weight | approx. 230 g |
| Power supply | 3 × 1.5V AAA batteries |
| Battery included | No |
| Certifications | CE, FCC |
| Safety rating | CAT III 1000V / CAT IV 600V (EN61010 series) |
| High-concern chemicals | None |
| Smart device | No |
Measurement ranges and accuracy
| Function | Range | Accuracy |
|---|---|---|
| DC voltage | 99.99mV / 999.9mV / 9.999V / 99.9V / 1000V | ±(0.5% + 3) |
| AC voltage | 99.9mV / 999.9mV / 9.999V / 99.9V / 750V | ±(0.8% + 3) |
| DC current | 9.999mA / 99.99mA / 999.9mA | ±(0.8% + 3) |
| DC current | 9.99A | ±(1.2% + 3) |
| AC current | 9.999mA / 99.99mA / 999.9mA | ±(1.0% + 3) |
| AC current | 9.99A | ±(1.5% + 3) |
| Resistance | 999.9Ω / 9.999kΩ / 99.99kΩ / 999.9kΩ | ±(1.0% + 5) |
| Resistance | 9.999MΩ / 99.99MΩ | ±(2.0% + 10) |
| Capacitance | 9.999nF / 99.99nF / 999.9nF / 9.999µF / 99.99µF / 999.9µF | ±(4.0% + 3) |
| Capacitance | 9.999mF / 99.99mF | ±(5.0% + 5) |
| Frequency | 99.99Hz / 999.9Hz / 9.999kHz / 99.99kHz / 999.9kHz / 9.999MHz | ±(1.0% + 3) |
| Duty cycle | 01.%–99.99% | ±(1.0% + 2) |
| Temperature | -40 to 1000°C / -40 to 1832°F | 2°C (as listed) |
Functions and features
| Feature | Supported |
|---|---|
| True RMS | Yes |
| Smart auto identification (V/Ω/continuity) | Yes |
| Auto identification of current input | Yes |
| REL measurement | Yes |
| MAX / MIN / AVG | Yes |
| NCV / Live / continuity test | Yes (sound & light alarm) |
| Diode test | Yes (sound alarm) |
| Data hold | Yes |
| Fuse burning prompt | Yes |
| Input jack LED indication | Yes |
| Low battery indication | Yes |
| Auto power off | Yes |
| Flashlight | Yes |
Model Variants
Single model version: GD128
Package Includes
- 1 × GD128 multimeter
- 1 × Test lead set (pen cable)
- 1 × Cloth bag
- 1 × Thermocouple temperature probe