Hoymiles HMT-1800-4T1800VA three-phase microinverter for four PV modules

Overview

The HMT-1800-4T converts four PV modules into 1800VA of balanced three-phase power at 230/400V. Its four inputs, two on each MPPT, take up to 15A each and suit modules from 360W to 600W and above according to Hoymiles. Rated output current is 2.61A per phase, and up to 12 units can be connected on a 10AWG branch. The integrated grid protection relay, isolated transformer and IP67 rating are common to the series, and data reaches S-Miles Cloud through a DTU-Pro-S or DTU-Lite-S.

• Three-phase 230/400V output, 3W+N+PE
• Four module inputs on two MPPTs
• Up to 16A per input for 182mm and 210mm cell modules
• Integrated grid protection relay
• Sub-1G link to DTU-Pro-S or DTU-Lite-S
• IP67, -40…+65°C, no fans

How it works

HMT-4T microinverters take four PV modules and feed balanced power into a three-phase 230/400V grid with neutral and protective earth. The four inputs are grouped on two MPPT trackers, two inputs each, working between 16V and 60V with a 65V maximum and a 22V start-up voltage. Input current reaches 16A on the HMT-2000-4T, which Hoymiles specifies for modules built with 182mm and 210mm cells. A grid protection relay is integrated, and the isolated HF transformer separates DC and AC.

Hoymiles positions the three-phase output for commercial and industrial applications as well as homes with a three-phase supply, since each unit feeds all three phases. When all units report to a DTU-Pro-S, the gateway can also limit phase imbalance of the whole system to below 3.68kW where required.

Installation and compatibility

Each unit is bolted to the racking with an 8mm screw at 9Nm, and grounding cleats are tightened to 2Nm. AC connection uses Hoymiles' three-phase trunk cable with L1, L2, L3, N and PE; the neutral must be correctly connected, otherwise the unit reports a wiring fault. Hoymiles allows 11 to 13 units per 10AWG branch and 6 to 8 per 12AWG branch at 230/400V, depending on the model; local rules decide the final number.

Monitoring and standards

Monitoring uses Sub-1G radio, and the manual states that the HMT-4T is compatible only with the Hoymiles DTU-Pro-S and DTU-Lite-S gateways, which send module-level data to S-Miles Cloud. CEC peak efficiency is 96.5% for all three models, nominal MPPT efficiency 99.8% and night consumption below 50mW. Compliance covers VDE-AR-N 4105:2018, EN 50549-1:2019, VFR 2019, IEC/EN 62109-1/-2 and IEC/EN 61000 EMC standards, and the standard warranty in Europe is 12 years.

Questions and answers