Schneider Electric 890USE17700 manual Configuring a, Reflex Action, Inputs to a Reflex

			Advanced Configuration Features
Configuring a	Each block in a reflex action must be configured using the Advantys configuration
Reflex Action	software.
	Each block must be assigned a set of inputs and a result. Some blocks also require
	that you specify one or more user-preset values—a compare block, for example,
	requires that you preset threshold values and a delta value for hysteresis.
Inputs to a Reflex	The inputs to a reflex block include an enable input and one or more operational
Action	inputs.The inputs may be constants or they may come from other I/O modules on
	the island, from virtual modules or outputs from another reflex block. For example,
	an XOR block requires three inputs—the enable and two digital inputs that contain
	the Boolean values to be XORed:
	enable	XOR
	operational input 1		result
	operational input 2
	Some blocks, such as the timers, require reset and/or trigger inputs to control the
	reflex action. The following example shows a timer block with three inputs:

enable

trigger

reset

timer

time unit x terminal count

result

The trigger input starts the timer at 0 and accumulates time units of 1, 10, 100 or 1000 ms for a specified number of counts. The reset input causes the timer accumulator to be reset.

An input to a block may be a Boolean value, a word value, or a constant, depending on the type of reflex action it is performing. The enable input is either a Boolean or a constant always enabled value. The operational input to an block such as a digital latch must always be a Boolean, whereas the operational input to an analog latch must always be a 16-bit word.

You will need to configure a source for the block’s input values. An input value may come from an I/O module on the island or from the fieldbus master via a virtual module in the NIM.

Note: All inputs to a reflex block are sent on a change-of-state basis. After a change-of-state event has occurred, the system imposes a 10 ms delay before it accepts another change of state (input update). This feature is provided to minimize jitter in the system.

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