The gCAT4 SWING Warning and Operator Technique

The SWING warning on a gCAT4 tells you that you are moving the locator incorrectly, usually swinging it like a pendulum or holding it off-vertical. It matters because a swung CAT gives unreliable readings and can mask a buried cable. The fix is simple: hold the unit upright and still, and let the response settle before you trust it.

SWING is one of the smartest features on a modern Radiodetection locator, and one of the most misunderstood. Here is what it is actually measuring and how to keep it quiet.

What is the SWING warning?

The gCAT4 contains motion sensors that monitor how you handle it. If you swing the unit from side to side as you walk, or tilt it away from vertical, the geometry of the detection changes from moment to moment and the readings become inconsistent. SWING flags that behaviour so you correct it. It is essentially the locator coaching your technique in real time.

Why does swinging cause missed cables?

A CAT detects the field around a buried service by its position and orientation relative to that field. Swing the unit and you are constantly changing both. The response jumps around, peaks get smeared, and a genuine signal from a shallow cable can be lost in the noise of your own movement. A steady, vertical sweep produces a clean, repeatable peak you can actually trust.

How do you stop triggering it?

• Hold it vertical. Keep the CAT upright, not angled forward or to the side.
• Walk, do not wave. Move the whole unit smoothly along the ground rather than swinging it from the wrist.
• Slow down. A controlled pace lets the unit and the operator settle.
• Pause to confirm. When you get a response, stop, hold steady, and read it properly.

SWING and data logging

On data-logging units, SWING events can be recorded as part of the sweep history. For a fleet manager that is useful: it shows whether operators are using correct technique, not just whether they switched the unit on. It turns a vague "they have a CAT" into evidence of competent use. There is more on this in our gCAT4 data-logging guide.

The takeaway

Treat SWING as a coach, not a nuisance. If it is going off, your technique is costing you accuracy. Hold the unit upright, move it smoothly, and confirm responses from a standstill. Combine that with the habits in tips for accurate cable locating and keep your unit calibrated so good technique meets a trustworthy instrument.