How to set up a Deye tetraphase inverter on a 3x220V network without a neutral conductor

Adapting a solar inverter to the specifics of the local grid is essential for performance and safety. In Belgium, there are still three-phase 3×220 V networks without neutral (IT network). The good news is that Deye hybrid inverters can be configured for this situation. In this guide, Wattuneed explains the complete procedure, the protections to be applied, and points you in the direction of compatible solar kits, solar batteries and solar inverters. When and why should an inverter be set for 3×220 V without neutral? IT networks (without neutral) require LL (phase-phase) thresholds and a dedicated parameter(IT system - neutral is not grounded). Without this setting, you risk unwanted tripping and erratic network monitoring. This guide is intended for installers and informed individuals who wish to integrate a Deye hybrid inverter into a 3×220 V installation. Technical requirements Compatible three-phase Deye UPS (e.g. SUN-10K-SG04LP3-EU, SUN-12K-SG04LP3-EU, SUN-8K-SG04LP3-EU, or SUN-15K-SG05LP3-EU). HMI version of the inverter allowing 133/230 V setting ( Device Info menu). Safety measures: AC/DC disconnection, PPE, insulation checks, local compliance. Step-by-step setting procedure (IT network 3×220 V, without neutral) 1) Check software version Open Device Info and check the HMI version. As of recent versions, the LL: 230 VAC setting and the IT system option are available. 2) Select the grid standard Menu Grid Setting → Grid selection Grid Frequency: 50 Hz (or 60 Hz depending on site) Grid Level: select LL : 230 VAC (do not select LN) IT system - neutral is not grounded: activate 3) Set the voltage and frequency ranges In Grid Setting → Connect: Low frequency: 45.0 Hz High frequency: 65.0 Hz Low LL voltage: 180 V LL high voltage: 200 V In Reconnect after trip: Low frequency: 57.0 Hz High frequency: 61.0 Hz Low LL voltage : 110 V High LL voltage: 200 V Reconnection delay: 60 s 4) IP protection (voltage/frequency) Overvoltage (10 min average): 260 V Normal ramp rate: 18 Reconnection ramp rate: 36 Protection Stage 1 Stage 2 Umax 265 V 265 V Umin 100 V 100 V Fmin 47 Hz 57 Hz Fmax 57 Hz 62 Hz Good practice and quality control Consistency test: validate three-phase detection, then simulate thresholds (bench or drive) to check tripping. Insulation measurement: essential for IT networks. Event log: collect logs after commissioning. EMS: Time-of-Use, zero injection, Smart Load Once the UPS has been configured, take advantage of the EMS functions to optimise your self-consumption: Time-of-Use: schedule battery charge/discharge according to tariffs (off-peak/peak). Zero injection: limit export with CT (practical in Belgium to stay below 3.68 kVA injection). Smart Load: control a non-critical load (e.g. water heater) with PV surplus. For an overview of Deye's advanced functions: 12 advanced Deye functions. Simple economic analysis (Belgium/France) With the zero-injection option and a large solar array (e.g. Pylontech US5000 - 4.8 kWh), you can use the PV surplus instead of injecting it for free. In peak hours at 0.28-0.35 €/kWh, discharging 5 kWh/day represents 1.40-1.75 €/day, or 500-640 €/year. With 2 modules (≈ 9.6 kWh useful), tariff smoothing and comfort climb, while respecting the 3.68 kVA constraint. "On a 3×220 V site, switching a Deye to IT mode and activating Time-of-Use enabled us to reduce grid peaks and increase self-consumption by more than 25%." Use case: house + EV charging Example: house 3×220 V without neutral, 6 kWp of panels, Deye 10 kVA, and 9.6 kWh in Pylontech. Programming: 00:00-06:00: off-peak EV + battery charging (power ceiling) 06:00-22:00: battery discharge (priority for domestic loads) 22:00-00:00: minimum SOC maintained (safety shutdown) Result: fewer kWh purchased at peak times and greater solar gain. Recommended products (Wattuneed selection) Deye hybrid inverters: SUN-8K, SUN-10K, SUN-12K, SUN-15K Lithium solar batteries: Pylontech US5000 4.8 kWh, Pylontech US2000C 2.4 kWh Ready-to-use solar kits : Our solar kits (self-consumption & storage) CTA - Take action 👉 Discover the Deye hybrid inverter range : SUN-8K | SUN-10K | SUN-12K 👉 Size your solar battery: Pylontech US5000 👉 Choose a self-consumption solar kit: See the kits FAQ Can a Deye work without neutral?Yes, by activating IT system - neutral is not grounded and choosing LL: 230 V. What thresholds do you recommend for 3×220 V?See the protection table above (Umin/Umax, Fmin/Fmax) and adapt according to local constraints. Is zero export possible?Yes, via CT; practical for complying with the 3.68 kVA injection limit. What type of storage should I use?Pylontech lithium modules (US2000C/US5000) are modular and tried and tested. Can I add AC-coupled PV?Yes, Deye manages AC-coupling with frequency cut-off when the battery is full. Wattuneed contact details WattuneedRue Henripré 12, 4821 Andrimont, Belgium📞 +32 87 45 00 34 - 📧 info@wattuneed.com Deye screen adjustment diagram (alt: "Deye solar inverter adjustment in 3×220 V without neutral") Photo IT electrical cabinet (alt: "Three-phase 3×220 V IT network without neutral") Visual of Deye + Pylontech pack (alt: "Solar kit with hybrid inverter and solar battery") "Wattuneed provided me with the exact parameters for the 3×220 V: smooth commissioning and zero network hazards."