Electrical Connection¶
The input/output module is plugged on the I/O Terminal Unit TU531 or TU532 I/O Terminal Units TU531 and TU532 for I/O expansion modules. Properly seat the module and press until it locks in place. 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 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 the S500 System Data S500 System Data, Overview chapters.
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 1.7 | unused | |
| 2.0 and 3.0 | I0 and I1 | Input signals for the digital inputs I0 and I1 |
| 4.0 | N01 | Neutral conductor for the digital inputs I0 and I1 |
| 2.1 and 3.1 | I2 and I3 | Input signals for the digital inputs I2 and I3 |
| 4.1 | N23 | Neutral conductor for the digital inputs I2 and I3 |
| 2.2 and 3.2 | I4 and I5 | Input signals for the digital inputs I4 and I5 |
| 4.2 | N45 | Neutral conductor for the digital inputs I4 and I5 |
| 2.3 and 3.3 | I6 and I7 | Input signals for the digital inputs I6 and I7 |
| 4.3 | N67 | Neutral conductor for the digital inputs I6 and I7 |
| 2.4 | R0 | Common contact of the first relay output |
| 3.4 and 4.4 | NO0 and NC0 | NO and NC contacts of the first relay output |
| 2.5 | R1 | Common contact of the second relay output |
| 3.5 and 4.5 | NO1 and NC1 | NO and NC contacts of the second relay output |
| 2.6 | R2 | Common contact of the third relay output |
| 3.6 and 4.6 | NO2 and NC2 | NO and NC contacts of the third relay output |
| 2.7 | R3 | Common contact of the fourth relay output |
| 3.7 and 4.7 | NO3 and NC3 | NO and NC contacts of the fourth relay output |
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 DX531. 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.
Warning
:strong:Danger of life through electric shock!
The terminals of the module can carry 240 V voltage.
Make sure that all voltage sources (supply and process voltage) are switched off before you are beginning with operations at the system.
The module provides several diagnosis functions (see chapter Diagnosis and display Digital Input/Output Module DX531).
The following figure shows the electrical connection of the digital input/output module DX531.
Electrical connection of the digital input/output module DX531
Attention
:strong:Risk of damaging the PLC module!
The following things have to be considered when connecting input and output voltages to the module:
- All 230 V AC feeds must be single phase from the same supply system.
- Connection of 2 or more relay contacts in series is possible; however, voltages above 230 V AC and 3-phase loads are not allowed.
- The 4 switch-over contacts of the relays are electrically isolated from channel to channel. This allows to connect loads of 24 V DC and 230 V AC to relay outputs of the same module. In such cases it is necessary that both supply voltages are grounded to prevent unsafe floating grounds.
- All input signals must come from the same phase of the same supply system (together with the used neutral conductor). The module is designed for 120/230 V AC max., not for 400 V AC, even not between two input terminals.
- All neutral conductor connections must be common to the same supply system, since the terminals 4.0 to 4.3 are interconnected within the module. Otherwise, accidental energization could occur.
Attention
:strong:Risk of damaging the PLC module!
There is no internal short-circuit or overload protection for the relay outputs.
Protect the relay contacts by back-up fuses of 6 A max. (characteristic gG/gL). Depending on the application, fuses can be used for single channels or module-wise.