Commissioning Guide

Commissioning a Sigenergy SigenStor UK — Field Guide

Last updated 2026-06-13 · For UK solar and battery engineers

Products covered

This guide covers the SigenStor EC (Energy Controller) — Sigenergy's integrated hybrid inverter and battery system. Single-phase (SP) models run from 3.0 to 12.0 kW. Three-phase (TP) models from 5.0 to 30.0 kW. Battery packs (SigenStor BAT) are 5.0 or 8.0 kWh, up to 6 per inverter (maximum 48 kWh).

The Sigen Energy Gateway is required for EPS (backup power) or G100 (zero export) control. The Sigen Power Sensor (SDM230MODBUS) is required for export limitation. The Sigen CommMod provides 4G backup connectivity (2 years free data included).

Full fault code reference: Sigenergy fault codes on Faultpath.

Before you power up

DC SWITCH must be OFF. AC breaker (grid-side MCB) must be OFF. Confirm both before connecting any cables.

DC side: measure PV string open-circuit voltage against the inverter's maximum DC input. Correct any polarity reversal before closing the DC switch. Check all MC4 connectors are fully locked (audible click).

AC side: cable spec is 4–6 mm² outdoor 3-core copper (L, N, PE). MCB rating: 25 A for 3.0–4.0 kW SP; 40 A for 4.6–6.0 kW SP. Earth cable (4–6 mm² single-core copper) must be connected to the inverter ground screw. Per Sigenergy documentation: the PE connection must remain intact while the inverter is powered on.

CT clamp orientation — the most commonly missed step

CT clamp arrow must face toward the grid (away from the inverter).Fitting it backwards inverts the export/import reading. The inverter will export when it should not, or refuse to export when it should. Error 1018 ID3 (Meter communication fault) on first power-up almost always means CT clamp orientation or RS485 wiring.

The Power Sensor must be fitted at the grid connection point — on the tails between the grid meter and the distribution panel, not on the solar output cable.

Power-up sequence

From the official Sigenergy installation guide:

LED indicator meanings: DC solid blue = DC side running. AC solid blue = grid-connected. Energy storage flashing blue = charging. Energy storage flashing green = discharging. Signal solid blue = connected via Ethernet or Wi-Fi.

No internet on site? The inverter broadcasts its own Wi-Fi hotspot named after its serial number for 2 hours after first power-up. Connect the mySigen App to this hotspot and complete commissioning offline. Add the permanent network connection afterwards.

Power-off for servicing: hold the ON/OFF button for more than 3 seconds. Wait at least 10 seconds before powering on again. After powering off this way, use the same button to restart (not the app).

mySigen App setup

Installer account vs homeowner account: The installer account provides access to commissioning functions, grid code settings, export limitation parameters, firmware updates, and installer-level parameters. Register at sigenergy.com or via the app. Installer web portal: web-eu.sigencloud.com.

The homeowner account is created automatically when the installer creates the new system. An activation email is sent from sigencloud to the owner's email address. The owner must activate within 24 hours. If they miss this, push the notification again from the installer app.

Creating a new system: tap + from the Home screen, scan the SN code label from the packing box (or from the inverter side if the box label is unavailable), follow prompts for address and timezone, enter owner email, set grid code, set export parameters, save.

Important: Do not use Wi-Fi alone for new system creation. Sigenergy documentation states Ethernet or 4G (via CommMod) must be connected simultaneously with Wi-Fi. Using Wi-Fi alone prevents new system creation from completing.

UK grid settings — G98/G99

In mySigen: Home → station name → three-dot menu → System Settings → Grid Code. Select the United Kingdom profile.

G98 applies where total generation per phase is 3.68 kW or less (3.68 kW single-phase, 11.04 kW three-phase). Post-installation DNO notification required within 28 days. No pre-approval needed.

G99 applies above those thresholds. Most SigenStor EC 5.0 SP and above residential installs fall under G99. Submit Form A3-1 to the relevant DNO before commencing. Approval typically takes 8–12 weeks and may involve an assessment fee.

The UK grid code profile pre-populates voltage and frequency protection limits in compliance with G98/G99. Do not override these thresholds without written DNO consent.

Battery detection

SigenStor BAT units connect to the inverter via internal bus (mechanical stacking connectors). There is no separate pairing procedure. After power-up the inverter BMS scans the internal bus and registers all connected BAT units automatically.

Verify in mySigen: Home → station name → tap the SigenStor in the energy flow diagram → confirm correct number of BAT units is shown with visible SOC readings.

If batteries are not detected: power down (hold ON/OFF 3+ seconds), wait 30 seconds, check mechanical connectors between battery units are fully seated, then re-power. If still not detected, look for error 1018 ID2 (CAN communication fault).

Set discharge cut-off SOC to a minimum of 10%. Sigenergy documentation warns against 0% to avoid irreversible battery degradation.

Common commissioning faults

1002 ID1 — Low insulation resistance: PV string shorting to PE or cable damage. Common in the UK at first power-up when cables have been through damp roof spaces. Check DC cables and MC4 connectors for moisture. Retest after weather dries if the fault occurs on a wet day.

1005 ID1 — System grounding fault: PE earth cable not connected or loose. Check earth terminal.

1007 ID1 — String reversely connected: DC polarity swapped. Wait until dark (or PV current below 0.5 A), turn DC SWITCH off, swap MC4 connectors on the affected string.

1011 — Grid overvoltage (the most commonly reported UK alarm): UK grid voltage frequently runs at 240–248 V or higher. The inverter is correctly protecting itself under G98/G99. Check actual grid voltage with a calibrated meter. If consistently above 253 V, this is a DNO infrastructure issue, not an inverter fault. Do not raise the protection threshold without written DNO consent.

1018 ID3 — Meter communication fault: Power sensor RS485 wiring issue or CT clamp fitted backwards. Check RS485-2 wiring on COM terminal (pins 13/14), verify Power Sensor address (default: 1), check CT clamp arrow orientation.

1023 ID2 — Abnormal AC wiring: L and N swapped. Power down, verify terminal block wiring sequence.

1024 ID1 — Abnormal phase sequence (three-phase only): L1, L2, L3 in wrong order. Power down, swap any two phases at the AC terminal block.

Full Sigenergy fault code reference with causes, first check, and escalation guidance: Sigenergy fault codes on Faultpath.

G100 / zero export

In mySigen: Home → station name → three-dot menu → System Settings → Export/Import Limitation. Toggle Export Limitation ON. Set Maximum Power Export Limitation to 0 W.

Zero export requires the Sigen Power Sensor fitted at the grid connection point. Without it, the system has no grid reference and cannot limit export. For backup-capable systems requiring zero export, the Gateway is also required.

Export limitation settings are protected at installer level and cannot be changed by the homeowner.

DNO requirement check: Some DNOs accept the inverter's software limitation for G100. Others require a DNO-installed relay in addition. Confirm your specific DNO's requirement at application stage, before installation begins.
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