Electrical \ Connection¶
The analog 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 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 Units 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 | O0- to O7- | Minus poles of the first 8 analog outputs |
| 2.0 to 2.7 | O0+ to O7+ | Plus poles of the first 8 analog outputs |
| 3.0 to 3.7 | O8- to O15- | Minus poles of the following 8 analog outputs |
| 4.0 to 4.7 | O8+ to O15+ | Plus poles of the following 8 analog outputs |
Note
For the open-circuit detection (cut wire), each 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 V DC 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 V DC) and the ZP (0 V DC) terminals.
Caution
: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.
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 disturbances, no high requirement on precision), the shielding can also be omitted.
The following figure shows the electrical connection of the analog module AO523.
Terminal assignment of the analog output module AO523
The modules provide several diagnosis functions Analog Output Module AO523.