Special Features Of The Di/Dq 482 - Siemens S5-155U System Manual

8.1.4
Special Features of the
DI/DQ 482
Changeover of the I/O byte
System Manual
C79000-B8576-C199-03
To operate the module with process alarm via IB 0, you must observe
the following:
• • You may use up to eight alarm-generating modules.
• • The modules must all be inserted in the CC or all in the same EU.
• • You must operate the 432 module as the master. If you use two or
more 432 digital input modules with other alarm-generating
modules, you must operate one 432 as the master and all others as
slaves.
The DI/DQ 482 digital input/output module is an I/O module which
allows the processing of process signals in conjunction with the
IP 257, with the S5-135U/155U PLC and the EU 185U (see the IP 257
manual). Described in the following is the operation of the DI/DQ 482
without IP 257.
The DI/DQ 482 has 32 channels which are jointly isolated, i.e. there is
no subdivision into groups in the module. Channels 0.0 to 0.7 are
digital outputs, Channels 2.0 to 3.7 are digital inputs; Channels 1.0 to
1.7 can be optionally and individually operated as inputs or outputs.
The operation of Channels 1.0 to 1.7 as inputs or outputs merely
depends on the user program. You define the byte as an input with a
read access to the DI/DQ; you define the byte as an output with a
write access. The double-function of the byte also allows the output
byte to be read out.
Unused channels should not be wired nor addressed by program.
When these channels are used as inputs, it should be noted that the
corresponding bits in the output register remain at logic 0. This
resetting of output registers is executed automatically after power-up
of the PLC or EU.
Note
When at least one of Channels 1.0 to 1.7 is operated as an input,
the connected sensors and the 1L+ terminal must have the same
power supply. If this is not the case, the input voltage acts on the
1L+ terminal. The resultant supply to the output amplifiers of
Channels 0.0 to 1.7 causes currents to be drawn via the wired
input terminal; these currents may assume different values,
depending on the control states of the outputs.
Technical Description
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