Sunpura Smart Meter – 3-phase net metering with CT terminals

The Sunpura Smart Meter is the heart of energy monitoring in the Sunpura ecosystem. It measures both voltage (VA/VB/VC/N) and current per phase via CT terminals (IA/IB/IC/IN) and transmits that data wirelessly to the S2400 (Power Box). This allows the system to precisely control self-consumption, zero injection and battery charging/discharging.

How does it work?

• Voltage measurement: connect VA, VB, VC and N directly behind the main connection in the meter box. This way, the meter “sees” the mains voltage per phase.
• Current measurement with CT terminals: place a CT around L1, L2 and L3. Note the arrow/direction on the CT (towards the mains). The CTs go on terminals IA/IB/IC (reference IN).
• Wireless coupling: the Smart Meter transmits measurements to the S2400 via its built-in antenna, so no UTP or RS485 cabling is required. The S2400 manual explicitly shows the Smart Meter as part of the system.

What does this provide?

• Zero-injection/export-limiting: prevent feed-in when required or desired; the S2400 controls based on Smart Meter data.
• Maximum self-consumption: charge the battery when in surplus and deliver when in demand at home.
• Reliable control: because both voltage and current are measured per phase, control is stable and phase-correct.

Installation tips (practical)

1. Location: place the Smart Meter in the meter box, within Wi-Fi range of the S2400 app for commissioning.
2. Voltage connections: use fuse and correct wire assignment for VA/VB/VC/N. Label the phases to avoid mix-ups.
3. CT direction: arrow towards mains. Wrong direction gives negative currents and faulty control.
4. Phase mapping: keep L1↔IA, L2↔IB, L3↔IC consistent; check in the app if the phases are correct.
5. Testing: turn on a clear load and check if the real-time power matches (charge/discharge responds within seconds).

Short specification

• Connections: VA/VB/VC/N (voltage measurement), IA/IB/IC/IN (CT inputs).
• Communication: wireless to Sunpura S2400 systems (part of the Sunpura ecosystem).
• Application: 1- or 3-phase homes for monitoring, self-consumption optimisation and export limitation.