Siemens 505-2557 Manual De Usuario
Advanced Function Programming
3-6
SIMATIC 505–2557 Installation and Operation Guide
Internal Register Structures (continued)
Input registers WX49 – WX54 consist of special flag bits that may be
interrogated in the controller ladder program to detect alarm conditions,
overrange or underrange conditions, or arithmetic overflow conditions due
to scaling operations. See Figure 3-3.
interrogated in the controller ladder program to detect alarm conditions,
overrange or underrange conditions, or arithmetic overflow conditions due
to scaling operations. See Figure 3-3.
WX49
Channel 1–16
Alarm flag bits
WX50
Channel 1–16
High alarm flag bits
WX51
Channel 1–16
Low alarm flag bits
WX52
Channel 1–16
Overrange flag bits
WX53
Channel 1–16
Underrange flag bits
WX54
Channel 1–16
Arithmetic overflow flag bits
WX55
Channel 1–16
Open Thermocouple flag bits
WX56
Channel 1–16
Front panel temperature
.WX64 Reserved for future use
For each word, the bits are correlated to the channels according to the following
:
1
16
0
0
0
0
0
0
0
0
0
0
0
0
0
0
MSB
LSB
CH 1
.
.
.
CH 16
.
.
.
CH 16
Figure 3-3
Input Flag Bits
If the peak or valley hold functions are enabled and Y31=1, then the data
returned in WX49 – WX64 is the peak (Y30=1) or valley (Y30=0) value
measured. See Table 3-3.
returned in WX49 – WX64 is the peak (Y30=1) or valley (Y30=0) value
measured. See Table 3-3.
Table 3-3
Peak/Valley Hold Input Words
WX 49
Channel 1
Peak/Valley value
.
.
.
.
.
.
WX 64
Channel 16
Peak/Valley value