Phase sequence and motor rotation direction tester Unit UT261B, 90–600 VAC, 15–400 Hz

The Unit UT261B is a professional-grade phase sequence and motor rotation direction tester engineered for precise electrical diagnostics in three-phase systems. This handheld device allows technicians to quickly verify the phase sequence of power lines and determine the rotation direction of three-phase motors, ensuring that equipment is wired correctly before full operation. With a broad operating range of 90 to 600 VAC and a frequency response between 15 and 400 Hz, it provides reliable performance across a wide variety of industrial and commercial electrical environments.

Advantages

This tester offers significant benefits for electrical maintenance and installation by providing clear, non-contact indication of phase status. Its robust design ensures durability in demanding work conditions, while the intuitive interface allows for rapid testing without complex setup procedures. By accurately identifying phase order and motor rotation, the device helps prevent mechanical damage and operational failures caused by incorrect wiring, ultimately saving time and reducing maintenance costs during system commissioning or troubleshooting.

Suitable for

• Verifying phase sequence in three-phase power distribution systems
• Checking motor rotation direction during installation or maintenance
• Troubleshooting electrical wiring issues in industrial machinery
• Commissioning new three-phase electrical equipment

When it may not be suitable

This device is not designed for use on low-voltage circuits below 90 VAC or high-voltage systems exceeding 600 VAC. It is intended specifically for three-phase applications and will not function on single-phase AC or DC power systems.

Key specifications

• Operating voltage: 90–600 VAC
• Frequency range: 15–400 Hz
• Phase sequence indication: Yes
• Motor rotation indication: Yes
• Power source: Battery operated

How to use

To use the device, connect the provided test leads to the corresponding phases of the power source or motor terminals according to the color-coded markings. Once connected, the tester will indicate the phase sequence or motor rotation direction through its visual display. Ensure that the test leads are securely attached to the terminals to obtain an accurate reading and always follow standard electrical safety protocols when working with live circuits.

What to consider before purchase

• Verify that your electrical system operates within the 90–600 VAC range
• Ensure the device is compatible with your specific three-phase motor configuration
• Check if the frequency of your power supply falls within the 15–400 Hz range

Usage recommendations

Always inspect the test leads for any signs of damage or wear before each use. Ensure the device is kept clean and dry, and store it in a protective case when not in use to maintain measurement accuracy and longevity.