Honeywell AUTOMATIC CONTROL User Manual

ENGINEERING MANUAL OF AUTOMATIC CONTROL
CONTROL FUNDAMENTALS
35
CHARACTERISTICS AND ATTRIBUTES OF CONTROL METHODS
Review the columns of Table 4 to determine the characteristics and attributes of pneumatic, electric, electronic, and
microprocessor control methods.
Table 4. Characteristics and Attributes of Control Methods.
Pneumatic Electric Electronic Microprocessor
Naturally
proportional
Requires clean
dry air
Air lines may
cause trouble
below freezing
Explosion proof
Simple, powerful,
low cost, and
reliable actuators
for large valves
and dampers
Simplest
modulating
control
Most common for
simple on-off
control
Integral sensor/
controller
Simple sequence
of control
Broad
environmental
limits
Complex
modulating
actuators,
especially when
spring-return
Precise control
Solid state
repeatability and
reliability
Sensor may be
up to 300 feet
from controller
Simple, remote,
rotary knob
setpoint
High per-loop
cost
Complex
actuators and
controllers
Precise control
Inherent energy management
Inherent high order (proportional plus integral)
control, no undesirable offset
Compatible with building management system.
Inherent database for remote monitoring,
adjusting, and alarming.
Easily performs a complex sequence of control
Global (inter-loop), hierarchial control via
communications bus (e.g., optimize chillers based
upon demand of connected systems)
Simple remote setpoint and display (absolute
number, e.g., 74.4)
Can use pneumatic actuators

Honeywell AUTOMATIC CONTROL Specifications

General

Brand	Honeywell
Model	AUTOMATIC CONTROL
Category	Controller
Language	English