ABB ControlIT 53MC5000 User Manual

6.0 CS1 - SINGLE LOOP CONTROLLER
6.1 CS1 - SINGLE LOOP (PID) CONTROLLER
A single loop 53MC5000 Controller is configured at the factory for CS1 operation to provide the
standard displays listed in Table 6-2 and the default datapoint settings listed in Table 6-3. As a
Single Loop (PID) Controller, the Proportional Band is set at 100%; the Process Variable AI0 is
scaled 0-100% for a linear 4-20 mA input signal; and AO0 is set as a reverse action (PV above set-
point causes decreasing value) control signal over a 4-20 mA signalling range. These settings
may be altered and additional Control Strategy 1 (CS1) functions can be activated as necessitated
by the process application.
The Single Loop PID Controller is used in the majority of process applications. It calculates an out-
put from the difference between a Process Variable (PV) feedback signal sent from a Field Trans-
mitter (FT) (e.g., flow meter) and a setpoint (SP) value. The output is calculated with the controller
PID algorithm, which has
P
roportional,
I
ntegral, and
D
erivative terms. The effect these terms have
on the output calculation is determined by the PID datapoint configuration selections. After the out-
put is calculated, it is applied to a final control element (e.g., valve) to restore process flow to the
setpoint value. The controller output can be augmented with Additive Feed Forward (FF), which
adds a remotely generated analog value to the output, or it can be forced to track an analog input
signal. The output can also be set locally at the controller, whereby the PID algorithm calculated
output is not used. The setpoint can be set locally at the controller, set to track the primary vari-
able, or it can originate from a remote source. Datapoints must be configured to activate Additive
Feed Forward, Output Tracking, Setpoint Tracking, and Remote Setpoint. If the alarm limit data-
points are configured, the controller will activate an alarm annunciator whenever the PV exceeds
the configured tolerable limits of change. A typical low-resolution display Single Loop (PID) Con-
troller process application is illustrated in Figure 6-1.
Figure 6-1. Typical CS1 Single Loop Controller Application
PUMP
VALVE
FT
AI1 - REMOTE SETPOINT
AI2 - ADDITIVE FEED FORWARD
AI3 - TRACKING
DI0 - FORCE OUTPUT TRACKING
(OPEN CONTACT)
DI1 - REMOTE SETPOINT ENABLE
(CLOSED CONTACT)
AI0 - PROCESS VARIABLE
AO1 - RETRANSMITTED PV
DO0 - PROCESS ALARM 1
DO1 - PROCESS ALARM 2
AO0 - CONTROL OUTPUT
Section 6. CS1 - Single Loop Controller
6-1

ABB ControlIT 53MC5000 Specifications

General

Brand	ABB
Model	ControlIT 53MC5000
Category	Controller
Language	English