Two cases can occur for PLC station rack addressing:
Station built from a standard rack
The station is always limited to a single rack, thus the rack address is implicit and has a value of 0 (no microswitches).
Station built from extendable racks
For each station rack an address must be assigned. This address is coded using 4 microswitches found on the rack.
Microswitches 1 to 3 are used to code the address of the rack on the X-Bus (0 to 7), microswitch 4 is used to code two racks (4, 6 or 8 positions) on the same address. This latter functionality is managed by the programming software.
Diagram showing the microswitch
Table of rack addresses
NOTE: On delivery, microswitches 1, 2 and 3 are in the ON position (address 0).
Assigning addresses to different racks
Address 0: this address is always assigned to the rack which supports:
This rack can be located in any position in the chain.
Addresses 1 to 7: they can be assigned in any order to all the other extendable racks in the station.
NOTE: the rack address coding must be done before mounting the power supply module.
NOTE: If two or more racks are positioned at the same address (other than address 0), then the racks concerned as well as all their modules show a fault. After fixing the addresses, it is necessary to switch off and then switch on the racks concerned.
This note only applies to racks with references TSX RKY..EX
If two or more racks are at address 0, the rack supporting the processor does not show a fault.
