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Meters extend what a bare CT can do — and three-phase sensing adds one discipline a single-phase installer has never needed: phase matching.
For trained/authorized installers only. Meter wiring is live-side work; isolate first.

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When a meter instead of (or with) the CT

A supported energy meter carries its own CTs and reports over RS485 to the inverter — the route when the grid connection point is beyond the CT lead’s reach [KNB-VAL-23], when the scheme shipped that way, or for AC-coupled metering. One sensing scheme per site.

Kent M1 meter wiring options — figure KNB-M1-CR-10

  • Kent M1 supported meters, terminal mapping and the AC-couple CT schemes (3-CT on single-phase homes, 6-CT on three-phase supplies) are on Kent M1 CT & Meter.
  • Kent G3 meter scheme, pin map and kit ratios are on Kent G3 CT & Meter; meter installation location (Grid side / Load side / Grid + PV inverter) is selected at commissioning.

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RS485 polarity — A is A, B is B

Meter comms die on swapped polarity more than anything else. Land A on A and B on B exactly per the platform’s pin map — on the Kent G3 note the meter end and inverter end use different pin numbers for the same pair, so wire by signal name, not by pin habit. Symptom of a swap or a dead meter supply: meter comm fault, no grid data — the flow is on Troubleshooting: Comm Fault (Kent M1 · Kent G3).

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Three-phase discipline: match everything, per phase

On the Kent G3, three CTs must agree with three conductors and three terminal pairs:
  1. L1’s CT on the L1 conductor, its leads on the CT-L1 terminals — likewise L2 and L3. Right phases with crossed leads is still wrong.
  2. Every CT’s arrow toward the grid — the universal rule.
  3. Prove it per phase: step a known load on each phase in turn and watch that phase — and only that phase — respond on the display. 📷
The classic mismatch signature: one phase importing while another discharges on the same display. That is a phase-mapping error until proven otherwise.

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AC-coupled and multi-source sites

Where an existing grid-tie PV inverter shares the site, metering must see it — the Kent M1 manual’s AC-couple schemes put a CT on the grid and one on the existing solar inverter; the Kent G3 offers the Grid + PV inverter meter placement for the same idea.
Retrofit expectation: a third-party grid-tie inverter on the grid side has no control channel to the Kent hybrid — the system can meter it, not command it. Plan export behaviour accordingly and design multi-meter retrofits with Kent service before quoting.

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Common mistakes

  • A/B swapped at one end only — comm fault that “tests fine” with a continuity beep.
  • Meter powered from a circuit that is dead during the backup test — grid data vanishes exactly when you are watching.
  • Three CTs clipped in a hurry: right directions, wrong phases.
  • Mixed sensing: CTs and a meter both wired “to be safe” — one scheme per site.

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When to escalate