Electrical \ Connection¶
The modules are plugged on I/O terminal units TU515 or TU516 TU515, TU516, TU516-H and TU542 for I/O Modules. Properly position 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 TA526 - Wall Mounting Accessory).
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
For a detailed description of the mounting, disassembly and electrical connection of the module, please refer to the System Assembly chapter AC500-eCo.
The terminals 1.8 to 4.8 and 1.9 to 4.9 are electrically interconnected within the I/O terminal units and have always the same assignment, independent of the inserted module:
Terminals 1.8 to 4.8: process voltage UP = +24 VDC
Terminals 1.9 to 4.9: process voltage ZP = 0 V
The assignment of the other terminals:
| Terminals | Signal | Description |
|---|---|---|
| 1.0 to 1.7 | O0- to O7- | Negative poles of the first 8 analog outputs |
| 2.0 to 2.7 | O0+ to O7+ | Positive poles of the first 8 analog outputs |
| 3.0 to 3.7 | O8- to O15- | Negative poles of the following 8 analog outputs |
| 4.0 to 4.7 | O8+ to O15+ | Positive poles of the following 8 analog outputs |
Note
For the open-circuit detection (cut wire), each analog input channel is pulled up to “plus” by a high-resistance resistor. If nothing is connected, the maximum voltage will be read in then.
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 VDC power supply at the terminals L+/UP and M/ZP of the CPU/bus module increases by 2 mA per AO523.
The external power supply connection is carried out via the UP (+24 VDC) and the ZP (0 VDC) terminals.
Attention
:strong:Risk of damaging the PLC modules!
Overvoltages and short circuits might damage the PLC modules.
- Make sure that all voltage sources (supply and process voltage) are switched off before you begin with operations at the system.
- Never connect any voltages or signals to reserved terminals (marked with —). Reserved terminals may carry internal voltages.
Note
Generally, analog signals must be laid in shielded cables. The cable shields must be earthed at both sides of the cables. In order to avoid unacceptable potential differences between different parts of the installation, low resistance equipotential bonding conductors must be laid.
Only for simple applications (low electromagnetic disturbances, no high requirement on precision), the shielding can also be omitted.
The following figure shows the electrical connection of the module:
The modules provide several diagnosis functions AO523 - Analog Output Module.