For the single-phase output configuration, a special connector provided in the accessory kit must be fitted to all back panel cards. The back panel boards are located inside the machine behind the power modules. In the Trimod HE 10, 15 and 20 models, there is only one back panel board. In the Trimod HE 30-40 kVA TM model there are two back panel boards. The connector must be plugged into the position indicated with EC 15 in the board's serigraphy, as shown in the following figure.