Main Menu - Extended Closed-Loop - Tr200 - Group 21 - Trane TR200 Programming Manual

20-95 PID Differentiation Time
Range:
0.00 s* [0.00 - 10.00 s]
20-96 PID Diff. Gain Limit
Range:
5.0 N/A* [1.0 - 50.0 N/A]

Main Menu - Extended Closed-loop - TR200 - Group 21

21-** Ext. Closed-loop
The TR200 offers 3 extended closed-loop PID controllers in addition to the PID controller. These can be config-
ured independently to control either external servos (valves, dampers, etc.) or be used together with the internal
PID controller to improve the dynamic responses to setpoint changes or load disturbances.
The extended closed-loop PID controllers may be interconnected or connected to the PID closed-loop controller
to form a dual loop configuration.
In order to control a modulating device (e.g., a valve motor), this device must be a positioning servo motor with
built-in electronics accepting either a 0–10 V (signal from Analog I/O card MCB 115) or a 0/4–20 mA (signal from
control card and/or General Purpose I/O card MCB 101) control signal.
The output function can be programmed in the following parameters:
• Control Card, terminal 42: par.6-50
loop 1/2/3
• General Purpose I/O card MCB 101, terminal X30/8: par.6-60
or [149]...[151], Ext. Closed-loop 1/2/3
General Purpose I/O card and Analog I/O card are optional cards.
TR200 Programming Guide
Function:
The differentiator monitors the rate of change of the feedback. If the
feedback is changing quickly, it will adjust the output of the PID controller
to reduce the rate of change of the feedback. Quick PID controller re-
sponse is obtained when this value is large. However, if too large of a
value is used, the adjustable frequency drive's output frequency may
become unstable.
Differentiation time is useful in situations where extremely fast adjusta-
ble frequency drive response and precise speed control are required. It
can be difficult to adjust this for proper system control. Differentiation
time is not commonly used in TR200 applications. Therefore, it is gen-
erally best to leave this parameter at 0 or OFF.
Function:
The differential function of a PID controller responds to the rate of change
of the feedback. As a result, an abrupt change in the feedback can cause
the differential function to make a very large change in the PID control-
ler's output. This parameter limits the maximum effect that the PID
controller's differential function can produce. A smaller value reduces
the maximum effect of the PID controller's differential function.
This parameter is only active when par.20-95
not set to OFF (0 s).
Terminal 42 Output (setting [113]...[115] or [149]...[151], Ext. Closed-
Parameter Description
PID Differentiation Time
Terminal X30/8 Output, (setting [113]...[115]
is
4-169