promesstec UREG 200, Руководство пользователя

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7.2 Second set point
In some applications it is desirable to change the
setpoint automatically. Via the event input it is possible
to do this externally (see also chapter 7.1). The signal
for the event input can come from a timer, controller,
alarm relay or a manual switch. If the second setpoint is
to be switched via the event input set EIFN = SP2.
Prerequisite is that SPMD = SP1.2, MIN.R or HR.R
and MIN.R or HR.R is used for the ramp function (see
chapter 7.4).
SP2 example 1:
In a process it is necessary that the temperature is
increased when a certain pressure is reached. Set SPMD = SP1.2, EIFN = SP2 (or
SP.P2). A pressure switch switches on the event input at the set pressure, SP1
(Normal temperature) is determined by SP2 (increased temperature) is replaced.
(In this case the SP2 function SP2F = ACTU must be).
SP2 example 2:
An oven should have a temperature of SP1 = 300°C in the period from 8:00 to 18:00,
from 18:00 the temperature should be lowered to SP2 = 80°C. An external timer is
used to switch the event input at 18:00. The settings are, SPMD = SP1.2, EIFN =
SP2 and SP2F = ACTU.
7.3 Second PID setting
In some applications, the process behavior is
strongly dependent on the process value. The
UREG200 provides two PID settings. If the process
value changes above a certain limit, the second PID
setting can be activated in order to control optimally
in this range.
Automatic setting of the second PID values
The optimum PID values for a process vary with the process and setpoint value. If a
large setpoint range is provided for a process, the second PID values are required to
use the controller optimally. During the automatic setting, the first PID values (PB1,
TI1 and TD1) are stored when the event input is open. If during the automatic setting
the event input is closed and (EIFN = PID2 or SP.P2), the second PID values (PB2,
TI2 and TD2) are saved.
Example 1: external switching
Set EIFN = SP.P2 , by operating the event input the setpoint and the PID values are
set to the second values simultaneously.
Connection:
Event input +
Event input -
Settings:
EIFN = SP2 or SP.P2
Prerequisite:
SPMD = SP1.2 or
SPMD = MINR or
SPMD = HRR
Connection:
Event input +
Event input -
Setting:
EIFN = PID2 or SP.P2