Tempco TEC-2500, Инструкция по эксплуатации

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56
3–23 Manual Control
Manual control may be used for the following purposes:
1. To test the process characteristics to obtain a step response as well as an
impulse response and use these data for tuning a controller.
2. To use manual control instead of a closed-loop control if the sensor
fails or the controller's A-D converter fails. NOTE that bumpless transfer
can not be used for an extended time. See section 3-18.
3. In certain applications, it is desirable to supply a process with a constant
demand.
Operation:
Press and release until (hand control) appears on the display.
Press for 3 seconds, then release. The display will begin to flash and will
show . The controller is now in manual control mode.
Press ; the display will show and alternately where
indicates output 1 (or heating) “on” time % and indicates output 2 (or
cooling) “on” time %. Now you can use the up and down keys to adjust the
percentage values for H or C. This percentage of “on” time is in relation to
CYC1 for output 1 or CYC2 for output 2.
The controller performs open loop control as long as it stays in manual control
mode. The H value is exported to output 1 (OUT1) and C value is exported to
output 2 provided that OUT2 is performing cooling function (i.e., OUT2 selects
COOL).
Exception
If OUT1 is configured as ON-OFF control (i.e., PB1=0 if PB1 is assigned or
PB2=0 if PB2 is assigned by event input), the controller will never perform
manual control mode.
Exiting Manual Control
Press keys the and the controller will revert to its previous operating
mode (may be a failure mode or normal control mode).
Means
MV1=38.4% for OUT1 (or heating)
Means
MV2=7.63% for OUT2 (or cooling)