Eaton MTL 9493-PS-XXX Instruction Manual

Contents

14INM 9493-PS-XXX rev 14 5 Backplanes - earth railsOptional earth rails are available for backplanes (kit ERK08). Cable screens from hazardous-areacircuits, or spare pairs from a multicore cable, are connected to the terminals on the earth rails,which are mounted on the backplane at about the same height as the front of the modules, close tothe hazardous-area connectors. Earth rails are attached using the following procedure:–4 5 1 Earth rail kit (ERK08)See Figures 4.1, 4.9 and 4.10.a) Locate the earth rail mounting posts (1) at backplane centres C (Figures 4.1 and 4.9).b) Attach the mounting posts (1) with M3 x 12 screws (3) and washers (4) (Figure 4.9).c) Slide the earth rail (5) through the slots in the of the mounting posts (1) (Figure 4.10).d) Fit the earth terminal(s) (6) on the rail (5) (Figure 4.10).e) Attach plastic retaining rivets (7) to each end of the earth rail (5) (Figure 4.10).4 6 Backplanes – power supply connections4 6 1 Single backplaneDual 24V power supplies, to provide redundancy, are routed to the backplane by plug-in connectorsand then bussed by the backplane to individual power supply modules. LEDs on the backplaneindicate that the two supplies are operational. A diode circuit between the two ensures that thehighest voltage supply is the one in use at any given moment, so providing automatic switchover ofsupplies if the primary source fails. The procedure for connecting power supplies is:–a) Connect each of the two 21V to 35V dc power supply connectors to the independentsupply sources according to the terminal assignments shown in Figure 4.11. Themaximum permissible wire size is 2.5mm2 (14 AWG).b) Plug the power supply connectors into the base connectors on the backplanes.c) The rating for the fuse located between the two supply connectors on thebackplanes is 1A.4 6 2 Interconnection of power supplies for multiple backplanesPower supplies for backplanes can be interconnected in the form of a ring. This will reduce wiringand also permit individual backplanes to be taken out of service without affecting supplies to otherbackplanes. More than one backplane can be removed, provided that they are neighbours and donot leave any other backplanes without an active supply.a) Make the connections shown in Figure 4.12.Wire sizes up to 2.5mm2 (14 AWG) can be used and should be chosen according to loadand voltage drop.4 7 Fitting MTL 9493-PS-XXX modules to backplaneWARNING !When installing MTL 9492-PS-PLUS power supply modules it is essential to make sure thatintrinsically safe and non-intrinsically safe wiring is segregated as required by a nationally acceptedauthority or as described in BS EN 60079-14, ISA RP 12.6 or DIN VDE-165.4 7 1 Installation - Figure 4 15a) Trim insulation to suit bare or ferrule wire end (Figure 4.13)b) Terminate IS power wiring on blue connector(s).c) Mount interface unit on the backplane.d) Locate input bulk power connector(s) on backplane safe-area/power supply connector(s).4 7 2 Module removal - Figure 4 16a) Unclip the latch nearest the CE mark on the module label.b) Rotate the module away from this latch.c) When the module is unplugged from the power connector, move the module clear ofthe other latch and remove.