Trane TR1 6002, Инструкция по установке и эксплуатации

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PID for Process Regulation
The built-in proportional, integral, derivative (PID) controller in the
drive maintains a constant condition (pressure, temperature, flow, etc.)
in the system. It adjusts motor speed based upon a reference and/or
setpoint and the feedback signal. The PID controller is activated by
setting parameter 100, Configuration , to Closed loop .
A transmitter supplies the PID controller with a feedback signal from the
process to indicate its current state. The type of feedback signal in use
depends upon the type of process.
This means that deviations that occur between the reference/setpoint
and the actual process state are sensed. Such deviations are
compensated for by the PID regulator by adjusting the output frequency
as required by the difference (or error) between the reference/setpoint
and the feedback signal.
The PID controller in the drive has been designed for use in HVAC
applications and to perform a number of specialized functions.
Previously, it was necessary for a building management system to
handle these special functions by installing extra modules to program
the system.
With the TR1, there is no need for extra modules to be installed. Only
the reference and/or setpoint and a selected feedback signal need to
be programmed. An advanced feature of the TR1 is the drive’s ability to
accept two feedback signals, making two-zone regulation possible.
Voltage drop in long control cables can be compensated for by using
the scaling parameters for the analog inputs.
Feedback
The feedback signal must be connected to the drive according to the
table below, depending on the type of feedback signal and the settings
of the associated parameters listed.
Feedback type Terminal Parameters
Pulse 33 307
Voltage 53 or 54 308, 309, 310 or
311, 312, 313
Current 60 314, 315, 316
Bus feedback 1* 68 and 69 537
Bus feedback 2* 68 and 69 538
* The bus feedbacks can only be set by serial communication.
If two analog feedback signals are to be used, they both must be
voltage signals.
The Minimum Feedback and Maximum Feedback , parameters 413
and 414, must be set for the feedback signals. The type of process unit
for the signals is selected in parameter 415, Process Units .
Reference (Setpoint)
In parameter 205, Maximum Reference, the maximum value of the sum
of all reference signals is set.
The Minimum Reference , set in parameter 204, indicates the smallest
value that the resulting reference can assume.
The reference range cannot exceed the feedback range.
If multiple Preset References are required, use multiple setups or set
them in parameters 211 to 214 Preset Reference . See Reference
Handling .
If a current signal is used as a feedback signal, voltage can be used as
an analog reference. Use the table below to decide which terminal to
use and which parameters to program.
Reference type Terminal Parameters
Pulse 17 or 29 301 or 305
Voltage 53 or 54 308, 309, 310 or
311, 312, 313
Current 60 314, 315, 316
Preset reference 211, 212, 213, 214
Setpoints 418, 419
Bus reference * 68 and 69
* The bus reference can only be set by serial communication.
Terminals that are not used should be set to No function .
Inverse Regulation
Normal regulation means that the motor speed increases when the
reference/setpoint is higher than the feedback signal. Inverse regula-
tion means that the motor speed decreases when the reference/setpoint
is higher than the feedback signal. If there is a need for inverse
regulation, inverse must be programmed in parameter 420, PID
Normal/Inverse Control.
Anti-windup
The process controller is factory set with an active anti-windup function.
This function ensures that when either a frequency limit or a current limit
is reached, the integrator will be reset to zero. If the frequency limit or
current limit is cleared, the integrator will turn on again. This function
can be disabled in parameter 421, PID Anti-windup .
Start-up Conditions
In some applications, the optimum setting of the process regulator takes
a long time to reach. In such cases, a start-up frequency can be
entered in parameter 422, PID Start-up Frequency . The drive will
ramp directly to this frequency before PID control begins. This avoids
control by deviation between the reference/setpoint and the actual state
of the process during acceleration. It also avoids overshoot of the
process requirement during acceleration due to lag in the feedback
signal.