Schneider Electric SR2MAN01 Analog Comparators, Description, Use as a Contact, Normally open mode

LD Language Elements

Analog Comparators

Description	The Analog Comparators function block is used to:
	z Compare a measured analog value with an internal reference value.
	z Compare two measured analog values.
	z Compare two measured analog values with hysteresis parameter.
	The result of this comparison is used in the form of a contact.
	Analog automation functions can be used for smart relays with a real time clock and
	DC power supply, and with mixed DISCR/Analog inputs.
	The following indicate the existence of mixed Discrete/Analog inputs:
	z The existence of inputs numbered from IB to IG (maximum configuration). These
		inputs are used to receive analog signals from 0.0 V to 9.9 V inclusively.
	z The presence of the Analog Comparators function in the toolbar of the
		programming software.
	These smart relays have 16 Analog Comparators function blocks, numbered from
	1 to 9 then from A to G.
Use as a Contact
	The contact shows the position of a measured analog value in relation to a reference
	value or to another measured value.
	It may be used as many times as necessary in the program. It may be used
	according to 2 modes: normally open or normally closed, described below.
	Normally open mode:
	Symbol of the normally open contact associated with a, Analog Comparator:
		A-
	The contact is conducting when the comparison condition is verified.
	Normally closed mode:
	Symbol of the normally closed contact associated with an analog comparator:
		a-
	The contact is conducting when the condition is not verified.

SR2MAN01 11/2007 129