Honeywell UDC2500 User Manual

Page 62

Configuration

UDC2500 Universal Digital Controller Product Manual

4/07

Function Prompt

Lower Display

Selection or Range of Setting

Upper Display

English

Numeric

Code

English

Numeric

Code

Parameter

Definition

PDMR 3

PD WITH MANUAL RESET is used
whenever integral action is not wanted for
automatic control. The equation is computed
with no integral contribution. The MANUAL
RESET, which is operator adjustable, is then
added to the present output to form the
controller output.

Switching between manual and automatic
mode will be bumpless.

If you select PD with Manual Reset you can
also configure the following variations:

• PD (Two Mode) control,
• P (Single Mode) control.

• Set Rate (D) to 0.

ATTENTION Other prompts affected:
MANRST in the Tuning Set Up group

TPSC 4

THREE POSITION STEP CONTROL
(TPSC)—The Three Position Step Control
algorithm allows the control of a valve (or
other actuator) with an electric motor driven
by two controller relay outputs; one to move
the motor upscale, the other downscale
without a feedback slidewire linked to the
motor shaft. The deadband is adjustable in
the same manner as the duplex output
algorithm.

The Three Position Step Control algorithm
provides an output display (OUT) which is an
estimated motor position, since the motor is
not using any slidewire feedback. Although
this output indication is only an
approximation, it is “corrected” each time the
controller drives the motor to one of its stops
(0 % or 100 %). It avoids all the control
problems associated with the feedback
slidewire (wear, dirt, noise). When operating
in this algorithm, the estimated OUT display
is shown to the nearest percent (i.e., no
decimal).

Refer to the Operation section for motor
position displays.

As a customer configurable option, when a
second input board is installed, the motor
slidewire can be connected to the controller.