Honeywell UDC2800 User Manual

Function Prompt
Selections or Range of
Setting
Parameter Definition
setpoint (SP) to determine the sign
of the error (ERROR = PV–SP). The
ON/OFF algorithm operates on the
sign of the error signal.
In Direct Acting Control, when the
error signal is positive, the output is
100 %; and when the error signal is
negative, the output is 0 %. If the
control action is reverse, the
opposite is true. An adjustable
overlap (Hysteresis Band) is
provided between the on and off
states.
ATTENTION: Other prompts
affected: OUT Hysteresis
DUPLEX ON/OFF is an extension of
this algorithm when the output is
configured for a Duplex control
algorithm. It allows the operation of
a second ON/OFF output. There is a
deadband between the operating
ranges of the two inputs and an
adjustable overlap (hysteresis) of
the on and off states of each output.
Both Deadband and Hysteresis are
separately adjustable. With no relay
action the controller will read 50 %.
ATTENTION: Other prompts
affected: OUT Hysteresis and
Deadband
PID A PID A is normally used for three-
mode control. This means that the
output can be adjusted somewhere
between 100 % and 0 %. It applies
all three control actions—
Proportional (P), Integral (I), and
95
Chapter 4 - Configuration

Honeywell UDC2800 Specifications

General

Control Modes	PID, ON/OFF, Manual
Mounting	Panel Mount
Display	Dual 4-digit LED
Input Types	Thermocouple, RTD, mA, mV, V
Output Types	Relay
Power Supply	100-240 VAC, 50/60 Hz
Communication	RS-485 Modbus RTU
Enclosure Rating	NEMA 4X