Yudian AI-526, Инструкция по эксплуатации

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PV startup and PV preparation function (rdy function) :
At the beginning of starting a program, resuming a program after power cut or continuing to run a program after it is
just modified, the PV (process value) are often quite different from the set point. PV startup function and PV
preparation function can make PV and set point consistent, and avoid unexpected result. When PV startup function
enabled, the instrument will adjust the running time automatically to make the expected set point is the same as the
current PV.
For example, the program is set that the temperature will be raised from 25
℃
to 625
℃
in 600 minutes. But the current
PV is 100
℃
, then the instrument will automatically to run this program start from 75 minutes, that mean changed the
temperature raised from 100
℃
to 625
℃
in 525 minutes (600-75) min.
At the above situation(PV=100, SV=25, first step SV), when PV preparation function is enable, the alarm function will
be blocked at that time, and PV will be adjusted to approach SV until the deviation alarm condition is released (PV is
between SV-LdAL and SV+HdAL). After deviation alarm was off, the controller starts to run the program again.
Preparation function (rdy Function) is helpful to keep the integrity of the program, but it will prolong the program time
because the start of the program is postponed.
PV startup function is prior to PV preparation function. If both function are enabled, the system apply PV startup first, if
PV startup function works, PV preparation function will not be activated.
Curve fitting:
Curve fitting is adopted as a kind of control technology for AI-526P series instrument. As controlled process often has
lag time in system response, by the way of curve fitting the instrument will smooth the turning point of the linear