1138. (1.1.4.1.1-4) In actual applications, electrical connections associated with «R1, R2 and R3» of the transmitter to «R1, R2, and R3» of the indicators shown in figure «C» of the illustration are made by what means

Slip rings and brushes provide continuous electrical connection to rotating components like the transmitter's rotor (R1, R2, R3) and matching indicators, allowing rotation without conductor damage; other connection methods are unsuitable for rotating interfaces.