Description 1-3
SIMATIC 505–2557 Installation and Operation Guide
RTD
and/or millivolt signals are translated into a 14–bit digital word. Since
the PLC requires a 16–bit input word, the 14–bit value from the converter is
placed into a 16–bit word for transmittal to the PLC. As shown in the
following figure, of the two bits not used for the digital word, one is used to
show the sign of the word, while the other is used to note values which are
“overrange or underrange.”
Figure 1-1 Wor
d Input to the PLC fr
om the Module
Digital W
or
d Map