I. Basic Overview
Model: ME440
Product Type: Three-phase handheld meter
Application Areas: Power analysis, energy measurement
Supported Current Sensors: Voltage output current clamp, Rogowski coil (compatible with ST08, TRC, NRC series)
Supported Wiring Systems: Three-phase four-wire, three-phase three-wire, one-phase two-wire (L-N), one-phase two-wire (L-L), one-phase three-wire (L-L-N)
Harmonic Measurement: Can simultaneously measure 51st harmonic
Storage Configuration: 16GB card, supports USB download, default storage interval 1 minute
Appearance Parameters: Blue and white color scheme; Dimensions: 215×130×60mm; Weight: 850g
Display Screen: 3.5-inch TFT screen, resolution 480×320

II. Electrical Input Parameters
1. Current Input
Table Item Parameter Primary Current Range 600A: 0.5A~720A
3kA: 0.5A~3600A
6kA: 0.5A~7200A
Secondary current range (ST08 current clamp): 1mA~6A
Input voltage: 1/2⁷mV ~ 707mV
Overload capacity: 2V, 10s/hours
2. Power Supply and Power Consumption
Power Supply: Built-in 2 x 2900mAh lithium batteries, continuous operation for approximately 8 hours; supports 5V DC power supply
Power Consumption: 2000mW when screen is always on; 1800mW when screen is off
3. Terminal Blocks
Current Input: BNC connector
Voltage Input: Banana connector
DC Power Supply: DC 5.5×2.1 terminals

III. Button Function Description
Table
Button Label Name Function
A ▲ Up Arrow Cursor moves to the previous item
B ▼ Down Arrow Move cursor to the next item
C ◀ Left Arrow: Move cursor to the left item
D ▶ Right Arrow: Move cursor to the right item
E ESC Back button: Return to the previous menu
F INFO Information button: Enter the meter information interface
G OK Confirmation button: Enter the next menu interface
H Backlight button: Adjust the screen backlight, 5 adjustable levels
I Power button: Press and hold for 3 seconds to power on/off
IV. Wiring Instructions
Voltage line: Connect to the banana voltage input terminal of the device, corresponding to the A/B/C/N phase of the measured line;
Current sensor:
Current clamp: Connect to the BNC current input terminal, clamp into the corresponding phase cable;
Rogowski coil: Connect to the BNC current input terminal, wrap around the corresponding phase cable;
After the device is powered on, it can read voltage, current, power, harmonics, and other measurement data in real time.

V. Comparison with Mi550/MQ31 Analyzer
Table | Item | ME440 | Mi550 | MQ31 |
Form | Handheld | Handheld | Box-type Portable |
Battery Life | 8h | 6h | Powered by Main Circuit |
Weight | 850g | 850g | Approx. 5kg |
Protection Rating | Basic handheld protection IP30 | Whole unit protection, sensor up to IP68 |
Applicable Scenarios | Quick inspection, basic power measurement | High-precision power quality analysis | Long-term online monitoring, outdoor scenarios