Electrical Connection

The CS31 Bus Module is plugged on the CS31 Terminal Unit U551 or TU552 Terminal Units TU551-CS31 and TU552-CS31 for CS31 Bus Modules. Hereby, it clicks in with two mechanical locks. The Terminal Unit is 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 CS31 Terminal Unit. It is possible, to replace CS31 Bus Modules and I/O modules without loosening the wiring.

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 CS31 Bus 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 1.7	RS-485	CS31 bus interface
2.0 to 2.7	I0 to I7	8 digital inputs
3.0 to 4.7	C8 to C23	16 digital inputs/outputs

The supply voltage 24 V DC for the module’s electronic circuitry comes from the ZP/UP terminals.

The module provides several diagnosis functions CS31 Bus Module DC551-CS31 with Digital Inputs and Output).

Caution

Removal of energized modules is not permitted. All power sources (supply and process voltages) must be switched off while working on any AC500 system.

The following figure shows the electrical connection of the CS31 Bus Module DC551-CS31.

Electrical connection of the CS31 Bus Module DC551-CS31

Caution

:strong:Risk of influences to the connected sensors!

Some sensors may be influenced by the deactivated module outputs of DC551-CS31.

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.