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IDEC SmartRelay functions
IDEC SmartRelay Manual
226
Functional description
If the input A/M is set to 0, then the special function issues
output AQ with the value that you set with parameter Mq.
If the input A/M is set to 1, then automatic mode commences.
As an integral sum the value Mq is adopted, the controller
function begins the calculations.
Note
For further information on the controller basics please refer
to the Online Help for WindLGC.
The updated value PV is used to calculate in the formulas:
Updated value PV
= (PV
•
gain) + offset
• If the updated value PV = SP, then the special function
does not change the value of AQ.
• Dir = upwards (+) (timing diagram numbers 1. and 3.)
–
If the updated value PV > SP, then the special function
reduces the value of AQ.
–
If the updated value PV < SP, then the special function
increases the value of AQ.
• Dir = downwards (
–
) (timing diagram number 2.)
–
If the updated value PV > SP, then the special function
increases the value of AQ.
–
If the updated value PV < SP, then the special function
reduces the value of AQ.
With a disturbance, AQ continues to increase / decrease
until the updated value PV again corresponds to SP. The
speed with which AQ changes depends on the parameters
KC and TI.
If the input PV exceeds the parameter Max, then the updated
value PV is set to the value of Max. If the PV falls short of the
parameter Min, then the updated value PV is set to the value
of Min.
If the input R is set to 1, then the AQ output is reset. As long
as R is set, the input A/M is disabled.
Courtesy of Steven Engineering, Inc. ● 230 Ryan Way, South San Francisco, CA 94080-6370 ● General Inquiries: (800) 670-4183 ● www.stevenengineering.com