Extech 480400 Phase Sequence Tester

The Extech 480400 is built to simplify the task of verifying phase sequence in three‑phase systems, helping technicians avoid wiring errors, motor rotation issues, and mis‑phased supply connections. On connection to the three phases via the supplied colour‑coded alligator clips, the unit’s large multi‑line graphic LCD provides immediate feedback: which of the three lines (L1, L2, L3) are live, and whether the sequence is correct (clockwise) or reversed (counter‑clockwise) based on the wiring. The tester operates across a wide voltage range (40 V to 600 V AC) and can handle non‑standard frequencies from 15 Hz up to 400 Hz, which makes it suitable for many industrial, commercial or specialized three‑phase setups.The rugged form‑factor includes a double‑moulded housing for durability in field use, and wide‑jaw alligator clips for easier connection to insulated conductors. Importantly, this unit requires no separate battery — it draws operating power from the measured system itself.Typical physical size is about 130 × 69 × 32 mm and weight around 130 g, making it compact and portable.

Features

• Rated AC voltage range: ~40 to 600 V AC for phase sequence testing.

• Frequency range: 15 to 400 Hz, allowing use on non‑standard frequency systems.

• Graphical multi‑line LCD that clearly indicates which phases are live (L1, L2, L3) and the direction of phase rotation (clockwise or counter‑clockwise).

• No battery required — the unit is powered from the system being tested.

• Durable, double‑moulded housing designed for industrial field use.

• Supplied with three large colour‑coded alligator clips with wide jaws for easier connection to conductors.

• Compact and lightweight: approximately 130 × 69 × 32 mm and about 130 g.

• Safety rating: marked for CAT III–600 V in some datasheets.

• Suitable for three‑phase system diagnostics: helps identify reversed phase sequence which can prevent motor damage or erratic operation.

• Comes complete with cable and carrying pouch case.

Includes

• Cable
• Three large color coded alligator clips
• Pouch case