West Control Solutions KS98-1 User Manual

Page 90

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Not all inputs and outputs of a function block need to be connected. The following rule is applicable: open inputs are
without effect. Examples: totalizer, multiplier, AND gate. In some cases, the connection of an input has an additional
effect, if e.g. priority handling is concerned (programmer control inputs).

Function blocks are numbered by the engineering tool in the order of occurrence from 100 to max. 450 as standard. Cal -
culation of function blocks in the unit is dependent on this order. By changing the block number, the handling order is
adapted. Function blocks which can be used only once or with reference to the hardware (inputs/outputs) are always
within a numeric range of 0-100.

Function blocks are preset to a scanning rate (computing cycle) of 100 ms. The computing cycle can be increased to
800 in steps of 200, 400, whereby the processor load is reduced. Detailed information is given in the ET98 operating
manual.

The parameters of each function block are adjustable. Apart from an individual description for documentation purpo -
ses, the majority of blocks is provided with function-specific parameters. In addition to very special ones, some para -
meters are quite frequent. For these general values, the same identifiers are always used:

a, b, c, d

factors without special signification

a0, b0, ... x0, y0 appended 0 as a symbol for an offset

x0 = offset of an input, y0 = offset of an output

T, Ti

times in seconds (delays, pulse or pause duration)

Mode

These parameters are used to select function parameter setting by means of the described parameter
or by means of an analog input (dynamic parameter setting).

Digital control inputs for binary selection (e.g. SELV1 for selection of 4 analog values) are normally numbered from left
to right d1, d2. Note that d2 is the less significant bit despite numbers running in opposed direction. In all cases where
the bit order also expresses an order of values, please, refer to the documentation of the special block in the following
chapters.

9499-040-82711

III-90

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