KNX area/line coupler REG housing 2 TE ETS product family system devices Product type line coupler KNX Data Secure compatible from ETS 5.7.3 Function The coupler connects two KNX lines to each other in terms of data technology and ensures galvanic isolation between these lines. Line coupler LK Connection of a line to a main line (HL), optionally with or without a filter function. The coupler is logically assigned to the subordinate line. Area coupler BK Connection of a main line (HL) to an area line (BL), optionally with or without a filter function. The coupler is logically assigned to the subordinate line. Amplifier V Preparation and repetition of telegrams on a line, no filter function. Division of a line into max. 4 independent line segments (max. 3 parallel-connected line amplifiers per line). A separate power supply including choke is required for each line segment.