Window Comparators (Wco/Wcoi/Wco2); Odc/Oidc/O2Dc) - Hitachi SJ700B Series Instruction Manual

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.
- Output values of ODc, OIDc, and O2Dc are the same as those of WCO, WCOI, and WCO2, respectively.
Item
Terminal [11] to terminal
[15] functions
Alarm relay terminal
function
Maximum-limit level of
window comparators
O/OI/O2
Minimum-limit level of
window comparators
O/OI/O2
Hysteresis width of
window comparators
O/OI/O2
Operation level at
O/OI/O2 disconnection
O, OI, or O2
Max(100%)
Min(O/OI:0%)
(O2 :-100%)
WCO/WCOI/WCO2
ODc/OIDc/O2Dc
Function
code
C021-C025
C026
b060 (O ) "Minimum-limit level + hysteresis width*2
(minimum of 0)" to 100. (%)
b063 (OI)
"Minimum-limit level + hysteresis width*2
b066 (O2)
(minimum of -100)" to 100. (%)
b061 (O ) 0 to "maximum-limit level - hysteresis
width*2 (maximum of 100)" (%)
b064 (OI)
-100 to "maximum-limit level - hysteresis
b067 (O2)
width*2 (maximum of 100)" (%)
b062 (O )
0 to "(maximum-limit level - minimum-limit
b065 (OI)
level)/2 (maximum of 10)" (%)
b068 (O2)
b070 (O )
0 to 100 (%) or "no" (ignore)
b071 (OI)
b072 (O2) -100 to 100 (%) or "no" (ignore)
Hysteresis width
(b062,b065,b068)
Applied analog data
Applied analog data
Chapter 4 Explanation of Functions
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
Range of data
27
28
29
54
55
56
4 - 71
Related code
Description
ODc: Detection of analog input O
disconnection
OIDc: Detection of analog input OI
disconnection
O2Dc: Detection of analog input O2
disconnection
WCO: Window comparator O
WCOI: Window comparator OI
WCO2: Window comparator O2
Setting of maximum-limit level
Setting of minimum-limit level
Setting of hysteresis width for
maximum-limit and minimum-limit
levels
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)
Analog operation level at
disconnection (b070/b071/b072)
Minimum-limit level of window
comparator (b060/b063/b066)