1. Introduction
Thank you for choosing the Mastfuyi FY125/FY123A Full-Automatic Large Screen Digital Multimeter. This device is a smart, professional electrical tester designed for high-precision measurements with True RMS and 6000 counts. It features dual automatic and manual modes, intelligent burn protection, and a clear 4.2-inch display for effortless viewing. This manual provides essential information for safe and effective operation of your multimeter.
2. Setup
2.1 Battery Installation
The multimeter requires 3 x 1.5V AAA batteries (not included). To install or replace batteries:
- Locate the battery compartment on the back of the device.
- Open the battery cover.
- Insert the batteries, ensuring correct polarity (+/-).
- Close the battery cover securely.
2.2 Connecting Test Leads
Insert the red test lead into the 'INPUT' jack and the black test lead into the 'COM' jack for most measurements. For current measurements, refer to the specific instructions in the operating section.
3. Operating Instructions
The Mastfuyi multimeter offers both automatic and manual ranging modes for efficient and accurate measurements. The device automatically selects the appropriate measurement range in auto mode. Use the 'MODE' button to switch between different functions if needed.
3.1 General Operation Overview
3.2 Measurement Functions
The multimeter supports a wide range of measurements:
- AC Voltage & Frequency Measurement: Connect test leads to the circuit. The device will automatically display AC voltage and frequency.
- DC Voltage Measurement: Connect test leads to the DC source. The device will automatically display DC voltage.
- Resistance Measurement: Connect test leads across the component. The device will automatically display resistance.
- Continuity Test: Touch test leads to points to check for continuity. A buzzer will sound for continuity.
- Capacitance Measurement: Connect test leads to the capacitor. The device will display capacitance.
- Diode Measurement: Connect test leads to the diode. The device will display the forward voltage drop.
- AC Current Measurement: Ensure proper connection for current measurement (refer to device input jacks). The device will display AC current.
- DC Current Measurement: Ensure proper connection for current measurement (refer to device input jacks). The device will display DC current.
- Temperature Measurement: Use the included temperature probe (for FY125 model) to measure temperature. Long press the 'SEL' button to switch between Celsius (°C) and Fahrenheit (°F).
- Live Wire Detection: Insert a single test lead into a socket to determine neutral and live wires. The device will indicate live wire presence.
- NCV (Non-Contact Voltage) Detection: Place the top sensor of the device near an AC power source. The light and buzzer will change according to the voltage intensity (low, medium, high, or no voltage).
3.3 Additional Features
- Data Hold: Press the 'HOLD' button to lock the current data on the display.
- Flashlight: The built-in flashlight allows for measurements in dimly lit environments.
- Auto Power Off: The device features a 15-minute automatic shutdown when idle to save power.
4. Maintenance
- Cleaning: Wipe the device with a dry, soft cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the multimeter in a cool, dry place away from direct sunlight and extreme temperatures. If storing for extended periods, remove the batteries.
- Protective Case: The device comes with a shockproof and wear-resistant protective case for robust protection.
5. Troubleshooting
- No Display/Power: Check battery installation and ensure batteries are not depleted. Replace if necessary.
- Incorrect Readings: Verify test lead connections, ensure the correct measurement mode is selected, and check if the component being tested is functioning correctly.
- No Continuity Beep: Ensure the continuity mode is active and the circuit is complete.
- NCV Not Detecting: Ensure the NCV sensor is close enough to the AC source and the source is live.
6. Specifications
6.1 General Specifications
- Display Type: Digital Display
- Counts: 6000
- Operating Mode: Manual Range (also Auto Ranging)
- Is Smart Device: Yes
- Battery Included: No
- High-concerned chemical: None
- DIY Supplies: Electrical
- Certification: CE, FCC, RoHS
- Origin: Mainland China
6.2 Measurement Ranges
| Measurement | Range (FY125) | Range (FY123A) |
|---|---|---|
| AC Voltage | 1V-600V | 1V-600V |
| DC Voltage | 0.5V-600V | 0.5V-600V |
| AC Current | 10mA-10A | 10mA-500mA |
| DC Current | 10mA-10A | 10mA-500mA |
| Resistance | 50Ω-10MΩ | 50Ω-10MΩ |
| Capacitance | 1μF-60000μF | 1μF-6000μF |
| Frequency | 40Hz-6000Hz | 40Hz-1000Hz |
| Temperature | -20°C~1000°C / -4°F~1832°F | ❌ |
| Continuity | ✔️ | ✔️ |
| Diode | ✔️ | ✔️ |
| NCV Detection | ✔️ | ✔️ |
| Live Wire Detection | ✔️ | ✔️ |
| True RMS | ✔️ | ❌ |
| Data Hold | ✔️ | ❌ |
| Auto Power Off | ✔️ | ✔️ |
| Low Battery Reminder | ✔️ | ✔️ |
| Auto Ranging | ✔️ | ✔️ |
| Flashlight | ✔️ | ✔️ |
| Power Supply | 2x1.5V AAA batteries (Not included) | 2x1.5V AAA batteries (Not included) |
7. User Tips
- Always ensure the test leads are securely connected before taking measurements.
- For temperature measurements, allow the probe sufficient time to stabilize for accurate readings.
- Utilize the auto-ranging feature for quick and convenient testing, but switch to manual mode for specific range requirements or troubleshooting.
8. Warranty and Support
For warranty information, technical support, or service inquiries, please contact the manufacturer or your point of purchase. Keep your purchase receipt as proof of purchase.
9. Packing List
9.1 FY123A Model
9.2 FY125 Model
