What the CT is for
A CT (current transformer) clips around the grid conductor and reports the current flowing through it. From that, the inverter knows whether the site is importing or exporting, and how much — the signal that drives self-use logic, zero-export control and the power figures on the display. No healthy CT signal, no working control.The clamp rule
- The CT clamps around one conductor: the live. Clamping live and neutral together cancels the magnetic fields — the CT reads 0 W and the control logic goes blind.
- Close the clamp until it clicks fully shut — a half-latched CT under-reads.
- Where it clamps and which way the arrow faces is its own discipline: Direction & Location.
Ratio discipline
A CT reports a scaled-down current; the ratio setting tells the inverter the scale. Wrong ratio = every power figure wrong by a large factor, and export limits enforced against the wrong numbers.Lead length — the quiet killer
The CT’s analog signal is millivolt-class: long or improvised extensions pick up noise, and noise reads as phantom import/export that the control chases.- The Kent G3 box kit ships with a 1 m, 2.3 mm² CT lead — that is the design length.
CT scheme vs meter scheme
Both platforms can sense the grid either with CT(s) directly on the conductor or through a supported energy meter (which carries its own CTs and talks RS485 to the inverter). One scheme per site — if CTs are connected on the Kent G3, the smart meter is not essential. Platform specifics: Kent M1 CT & Meter · Kent G3 CT & Meter.Common mistakes
- CT around live + neutral — load reads 0 W.
- Ratio typed from memory instead of the shipped CT’s nameplate. [KNB-VAL-08]
- CT lead extended with random 1.5 mm flex “just two metres” — phantom export follows. [KNB-VAL-23]
- Half-latched clamp that never clicked — under-reads until someone leans on it.
When to escalate
Escalate to Kent New Energy service only — through your registered Kent partner channel or the Kent service desk details on your work order. Do not contact any third-party or component-manufacturer support line for a Kent-branded system: tickets outside the Kent channel are not tracked, not covered, and can void warranty handling.