Digital Earth Testers | UT522

The UT522 is a digital earth tester from UNI-T's UT520 series, specialized in measuring Earth Resistance and Earth Voltage. It features high precision and a design suitable for field work.

1. General Description

The device is designed to measure the grounding resistance of electrical equipment, lightning protection systems, and electrical wiring. It offers two measurement methods: 3-wire precise testing and 2-wire simple testing. It features a durable structure and double insulation for user safety.

2. Technical Specifications

• Earth Resistance: 0 ~ 40Ω (±2% + 20), 0 ~ 400Ω (±2% + 3), 0 ~ 4000Ω (±2% + 3)
• AC Earth Voltage: 0 ~ 400V (50Hz/60Hz, ±1% + 6)
• Display Count: 4000
• Power Supply: 6 x 1.5V Alkaline Batteries (AA)
• Display: 70.6mm x 34mm LCD with backlight
• Weight: Approx. 560g
• Dimensions: 160mm x 100mm x 70.5mm

3. Features

• Manual Range selection
• Data Storage: Up to 20 groups
• Auto Power Off: After 10 minutes of inactivity
• Data Hold function
• Poor connection/contact warning
• Over-range indicator (OL)
• Double Insulation Protection (CAT III 600V)
• Backlight for dark environments

4. How to Use

AC Earth Voltage Measurement

1. Turn the rotary switch to EARTH VOLTAGE.
2. Connect test leads to V and E terminals.
3. Place probes at test points; the value appears directly on the screen.

3-Wire Precise Earth Resistance Testing

1. Insert auxiliary earth spikes into the ground at intervals (typically 5 to 10 meters).
2. Connect colored leads to terminals: Green to E, Yellow to P, and Red to C.
3. Turn the dial to the highest range (4000Ω).
4. Press the TEST button; the button will light up and the value will be displayed.

5. Included Accessories

• Standard test leads (3 colors)
• Simple test leads (2 wires)
• Auxiliary earth spikes
• Cloth carrying bag
• User manual and batteries

The UT522 is an economical and professional choice for engineers and technicians inspecting electrical grounding systems.