Electrical Connection

The input/output modules are plugged on I/O Terminal Units TU515 or TU516 I/O Terminal Units TU515 and TU516 for I/O Expansion Modules. Properly seat the modules and press until they lock in place. The Terminal Units are mounted on a DIN rail or with 2 screws plus the additional accessory for wall mounting (TA526 Wall Mounting Accessory TA526).

The electrical connection of the I/O channels is carried out using the 40 terminals of the I/O Terminal Unit. I/O modules can be replaced without re-wiring the Terminal Units.

Note

Mounting, disassembling and electrical connection for the Terminal Units and the I/O modules are described in detail in S500 System Data S500 System Data, Overview.

The terminals 1.8 to 4.8 and 1.9 to 4.9 are electrically interconnected within the I/O Terminal Unit and have always the same assignment, independent of the inserted module:

Terminals 1.8 to 4.8: Process voltage UP = +24 V DC

Terminals 1.9 to 4.9: Process voltage ZP = 0 V

The assignment of the other terminals:

Terminals	Signal	Meaning
1.0 to 1.3	+24 V	4 x sensor power supply sources (loadable with 0.5 A in total)
1.4 to 1.7	0 V	0 V (reference potential)
2.0 to 2.7	C0 to C7	8 digital inputs/outputs
3.0 to 3.7	C8 to C15	8 digital inputs/outputs
4.0 to 4.7	C16 to C23	8 digital inputs/outputs

The internal power supply voltage for the module’s circuitry is carried out via the I/O-Bus (provided by a Bus Module or a CPU). Thus, the current consumption from 24 V DC power supply at the terminals L+/UP and M/ZP of the CPU/Bus Module increases by 2 mA per DC523.

The external power supply connection is carried out via the UP (+24 V DC) and the ZP (0 V DC) terminals.

Attention

:strong:Risk of damaging the PLC modules!

The PLC modules can be damaged by overvoltages and short circuits.

Make sure that all voltage sources (supply and process voltage) are switched off before you are beginning with operations at the system.

The modules provide several diagnosis functions Digital Input/Output Module DC523.

The following figure shows the electrical connection of the digital input/output module DC523.

Electrical connection of the digital input/output module DC523

Attention

:strong:Risk of influences to the connected sensors!

Some sensors may be influenced by the deactivated module outputs of DC523.

Connect a 470 Ω / 1 W resistor in series to inputs C16/C17 if using them as Fast Counter inputs to safely avoid any influences.