Rockwell Automation 5370-CMPK Color CVIM Module MATH-PAK User Manual

Page 57

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Chapter 4

Defining Formulas

4–42

The two sets of range limits have this relationship:

LF <=

LW

<= REFERENCE <= UW <= UF, where:

LF =

Low

FAULT RANGE

limit

LW =

Low

WARNING RANGE

limit

UW =

High

WARNING RANGE

limit

UF =

High

FAULT RANGE

limit

The REFERENCE value could be based, for example, on the “mean”
formula result from a trial series of inspections conducted with the Color
CVIM module running in learn mode.

Once you have set the

High

and

Low

WARNING RANGE

and/or

FAULT

RANGE

limits for a formula, you can assign the limits to output lines, which

would then be activated whenever the respective range limits were exceeded.

Formula status: If a formula inspection result lies within both the

FAULT

RANGE

and

WARNING RANGE

limits, a “pass” condition exists for that

formula. If the result lies outside a

WARNING RANGE

limit, but within

the

FAULT RANGE

limits, a

WARNING

condition exists for the formula.

In addition, if the formula result also lies outside the

FAULT RANGE

limits,

a

FAULT

condition also exists for that formula.

Formula result format/conversion: The result for a particular formula is
expressed in either fixed decimal point, or integer value, as appropriate for
the operands and operators in use. When you set the range limits, either the
integer format or fixed decimal point format is used by the Color CVIM
automatically, as appropriate for the type of result.

If the formula is changed after the range limits are set, so that the required
result format changes, the format of the range limit is converted
automatically. If a fixed point range limit is converted to integer format, the
range limit value is rounded to the nearest integer value.

Result Restrictions: Integer results for a formula are restricted to the range
of

"2,147,483,647. Fixed point (decimal) results for a formula are

restricted to the range of

"32767.000. If a formula result goes beyond the

allowable range, a result of 0 is returned, and the formula fails.

Master range status: The

FAULT

status for each formula has an effect on

an output called the

Master Range

. For each inspection, if any user-defined

FAULT RANGE

limit is exceeded, the

Master Range

status is activated; if

Master Range

is assigned to one of the output lines, the output line is

activated accordingly (see Chapter 11 in the Color CVIM User’s Manual for
information on the

Master Range

and output line assignment).

Multiple range limit assignment to a single output: You can assign more
than one range limit to a single

Results

output line. For example, you can

assign both the

High

and

Low

WARNING RANGE

limits to one

Results

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