Control Techniques UD70, Руководство пользователя

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UD70
Issue code: 70nu2
7-12 Reference
EXP
Syntax result = EXP (expression)
This mathematical function returns the exponential function (e
expression
).
Example X = EXP(4.5)
This returns the value 90.0171313.
See also
LN
instruction.
FILTER
Syntax
result% = FILTER (input_expression%, time
_
constant %)
result = FILTER (input expression, time
_
constant%)
This is a signal processing function which returns the output of a first-order
filter function with input expression as the input.
The time-constant of the filter depends on the value specified, and how
often the
FILTER
instruction is executed.
Example CLOCK{
#1.21 = FILTER (#7.01, 4)
}
For a clock timebase of 5ms, the effective filter time-constant would be 4 x
5ms = 20ms.
If a step change of 0 to 1000 is applied to parameter #1.21, the output of the
filter will be as shown in the following diagram.
Typically, the output reaches the final value after five time-constants.
This function must always be used in the
CLOCK, ENCODER
or speed tasks.