Hitachi SJ700-2 instruction manual WCO/WCOI/WCO2

Chapter 4 Explanation of Functions

4.2.77 Window comparators (WCO/WCOI/WCO2) (detection of terminal disconnection: ODc/OIDc/O2Dc)

Related code

C021 to C025: Terminal [11] to terminal [15] functions

- The window comparator function outputs C026: Alarm relay terminal function

b060/b063/b066: Maximum-limit level of window comparators O/OI/O2

signals when the values of analog inputs O, b061/b064/b067: Minimum-limit level of window comparators O/OI/O2

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

WCO/WCOI/WCO2

ODc/OIDc/O2Dc

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