OPTICAL MINI-STAR COUPLER FOR CENTRAL OPERATION OF 4 SIEMENS RELAYS V3/4, OR T103 WITH RTU. PROTECTION OPERATOR PROGRAM DIGSI V3/V4 1 OPTICAL INPUT AND 4 OPTICAL OUTPUS, CASCADABLE AUXILIARY VOLTG. 24-250V DC AND 60-230V AC WITHOUT CHANGEOVER WITH ALARM RELAY, CONNECTION PROTECTION RELAYS, PC OR MODEM VIA OPTICAL FIBRE CABLE 820NM, ST PLUG FOR MOUNTING ON RAIL