DEEP SEA ELECTRONICS PLC - Home Mega Global Solution

NOTE: - Only the “end” modules in the MSC link must have the 120Ω terminationresistor enabled (switch up). All other controllers must have the termination resistorsdisabled (switch down).15.3 MULTISET COMMUNICATIONS LINK SPECIFICATIONSParameterConnection typeCable impedanceMaximum cable resistanceMaximum cable capacitance (between conductors)Maximum cable capacitance (conductor to shield)Termination resistors (one at each end of cable run)Max number of 55x controllers per busMax cable lengthMax Spur length (see note 2 below)Recommended cableValueTwin conductors with screen. Ensure screenis connected to SCR terminal of everycontroller on the bus.120Ω0.050Ω/m75pF/m110pF/m120Ω 4W (switchable)16 (only 3 shown above for clarity)250m1m* BELDEN 9841 120Ω cable.NOTE :- * Deep Sea Electronics part number. 016 030WARNING! 120Ω impedance cable must be used for the MultiSet CommunicationsLink.Use of any other impedance cable may cause intermittent failures in communications,indicated by MSC alarms although the system may function normally during engine / paneltesting.NOTE 1: - The 120Ω terminator must be enabled on the first and last devices on thecommunications bus. See section header MSC Settings for further details.NOTE 2: - It is important that the MultiSet Communications Link cable is run from onemodule to the next in a ‘bus’ fashion. ‘Spurs’ off this bus should be avoided wherepossible, but where a spur is unavoidable; its length should be kept less than 1m from thebus cable.DSE Guide to Synchronising & Load Sharing PART 1 ISSUE5 18/3/04 AM 43