> ## Documentation Index
> Fetch the complete documentation index at: https://learning.kent.co.in/llms.txt
> Use this file to discover all available pages before exploring further.

# Kent G3 CT and Meter — Installation, Wiring, Ratios

> CT arrow-toward-grid rule, 16-pin block colour wiring, kit and ratio table, meter scheme RS485 wiring, and wrong-CT fault symptoms.

The Kent G3 senses grid power flow with three CTs — or with the optional meter scheme. Placement direction, phase mapping, and ratio setting all have exact rules, and the correct ratio depends on **which kit shipped with your unit**.

<Warning>
  **For trained and authorized installers only.** Isolate the AC conductors before clamping the CTs.
</Warning>

## The CT Rule

<Steps>
  <Step title="Use the in-box CT set">
    The in-box CT set is **compulsory** for a hybrid installation unless you are using the meter scheme. Do not substitute CTs from another job.
  </Step>

  <Step title="Clamp on the grid hot line">
    Clamp each CT on its phase's **hot line at the system grid connection point** — never on a load branch or sub-circuit.
  </Step>

  <Step title="Arrow toward the grid">
    The **arrow on the CT must point toward the grid**. Installed in the wrong direction, the hybrid cannot operate normally. This is the universal Kent CT rule across all platforms.
  </Step>

  <Step title="Match phase to phase">
    The L1 CT goes on the L1 conductor with its leads on the CT-L1 terminals. L2 CT on L2. L3 CT on L3. Phase-to-CT mismatch causes single-phase import or discharge errors.
  </Step>
</Steps>

## Wiring CTs to the 16-Pin Block

Route the CT leads through **COM3** (2 mm holes) to the 16-pin terminal block inside the wire box.

| CT lead colour | Connects to           | Pins      |
| -------------- | --------------------- | --------- |
| WHITE (S1)     | CT-L1 / CT-L2 / CT-L3 | 1 / 3 / 5 |
| BLACK (S2)     | CT-L1 / CT-L2 / CT-L3 | 2 / 4 / 6 |

Strip 9 mm. Use the spring-clamp method and tug-test every conductor after seating.

## Which Kit — and Which Ratio

| Kit                | Contents                             | CT ratio to set             |
| ------------------ | ------------------------------------ | --------------------------- |
| CT scheme (in box) | 100 A/50 mA CTs, 2.3 mm² × 1 m leads | **2000**                    |
| Meter scheme       | Three-phase meter + 120 A/40 mA CTs  | **3000 — set on the meter** |
| Parallel > 3 units | Separate kit: meter + 300 A/5 A CTs  | Per kit nameplate           |

<Warning>
  **Pending Kent validation.** \[KNB-VAL-08]

  The CT scheme and ratio per Kent SKU are under confirmation. Until published here: **read the ratio off the shipped CT's nameplate and set exactly that value.** The HMI default text of "3000" belongs to the meter-scheme CT — the box-kit CT ships at ratio 2000. Never assume the default is correct for your kit.
</Warning>

## Meter Scheme Wiring

If you are using the meter scheme instead of CTs:

* Meter RS485 connects to the inverter's **Meter RJ45**: RS485A on **pin 1**, RS485B on **pin 2**.
* On the meter side: **pin 13 = RS485B**, **pin 14 = RS485A**.

Choose one scheme per site — CT scheme or meter scheme, not both. Meter installation location (Grid side / Load side / Grid + PV inverter) is selected during commissioning.

## Wrong-CT Symptoms

If you see any of these, stop and check the CTs before proceeding:

* **Fast power fluctuation on the display** — check CT direction first.
* **Import/export signs are flipped** — CT installed backwards.
* **One phase importing while another discharges** — CT-phase mismatch (L1 CT on the L2 conductor, for example).
* **Load reads 0 W** — CT clamped around two conductors simultaneously.

**Witness test at commissioning:** with grid on and PV off, confirm import on all three phases. Then step a known resistive load per phase and watch each phase respond on its own. Photograph the result. 📷

## Common Mistakes

* Typing ratio 3000 for the box-kit 2000 CT — power readings wrong by a large factor. Read the nameplate; see the kit validation note above.
* CTs on the correct phases but leads landed on the wrong CT-L pins on the block.
* CT leads extended with random cable beyond the supplied 1 m design length.
* Meter RS485 A and B swapped — meter comm fault, no grid data.

## Related Pages

* [Kent G3 Commissioning](/g3/commissioning)
* [Kent G3 AC Wiring](/g3/ac-wiring)
* [Kent G3 Settings Reference](/g3/settings-reference)