Hitachi SJ700-2 - Manual (Page 134)

Chapter 4 Explanation of Functions
4 -
71
4.2.77 Window comparators (WCO/WCOI/WCO2) (detection of terminal disconnection:
ODc/OIDc/O2Dc)
- The window comparator function outputs
signals when the values of analog inputs O,
OI, and O2 are within the maximum and
minimum limits specified for the window comparator. You can monitor analog inputs with reference to
arbitrary levels (to find input terminal disconnection and other errors).
- You can specify a hysteresis width for the maximum-limit and minimum-limit levels of the window
comparator.
- You can specify limit levels and a hysteresis width individually for analog inputs O, OI, and O2.
- You can fix the analog input data to be applied to an arbitrary value when WCO, WCOI, or WCO2 is
output. For this purpose, specify a desired value as the operation level at O/OI/O2 disconnection
(b070/b071/b072). When "no" is specified, the analog input data is reflected as input.
C021 to C025: Terminal [11] to terminal [15] functions
C026: Alarm relay terminal function
b060/b063/b066: Maximum-limit level of window comparators O/OI/O2
b061/b064/b067: Minimum-limit level of window comparators O/OI/O2
Related code
- Output values of ODc, OIDc, and O2Dc are the same as those of WCO, WCOI, and WCO2, respectively.
Item
Function
code
Range of data Description
27
ODc: Detection of analog input O
disconnection
28
OIDc: Detection of analog input OI
disconnection Terminal [11] to terminal
[15] functions
29
O2Dc: Detection of analog input O2
disconnection
54 WCO: Window comparator O
55 WCOI: Window comparator OI
Alarm relay terminal
function
C021-C025
C026
56 WCO2: Window comparator O2
b060 (O )
b063 (OI) "Minimum-limit level + hysteresis width/2
(minimum of 0)" to 100. (%)
Maximum-limit level of
window comparators
O/OI/O2
b066 (O2)
"Minimum-limit level + hysteresis width/2
(minimum of -100)" to 100. (%)
Setting of maximum-limit level
b061 (O )
b064 (OI) 0 to "maximum-limit level - hysteresis
width/2 (maximum of 100)" (%)
Minimum-limit level of
window comparators
O/OI/O2
b067 (O2)
-100 to "maximum-limit level - hysteresis
width/2 (maximum of 100)" (%)
Setting of minimum-limit level
b062 (O )
b065 (OI) Hysteresis width of
window comparators
O/OI/O2
b068 (O2)
0 to "(maximum-limit level - minimum-limit
level)/2 (maximum of 10)" (%)
Setting of hysteresis width for
maximum-limit and minimum-limit
levels
b070 (O )
b071 (OI)
0 to 100 (%) or "no" (ignore) Operation level at
O/OI/O2 disconnection
b072 (O2) -100 to 100 (%) or "no" (ignore)
Setting of the analog input value to be
applied when WCO, WCOI, or WCO2
(ODc, OIDc, or O2Dc) is output.
Maximum-limit level of window
comparator (b061/b064/b067)
Minimum-limit level of window
comparator (b060/b063/b066)
WCO/WCOI/WCO2
ODc/OIDc/O2Dc
Max(100%)
Min(O/OI:0%)
(O2 :-100%)
O, OI, or O2
Applied analog data
Applied analog data
Analog operation level at
disconnection (b070/b071/b072)
Hysteresis width
(b062,b065,b068)