Johnson Controls Frick RWF II User Manual

RWF II ROTARY SCREW COMPRESSOR UNITS
OPERATION
070.610-IOM (JUN 11)
Page 18
QUANTUM
™
LX EZ-COOL
™
LIQUID INJECTION
ADJUSTMENT PROCEDURE
Use the following directions to set up and tune the EZ-Cool
LIOC with a Quantum
™
LX Control Panel. Also refer to publi-
cation 090-022 O, Quantum
™
LX Operation, for an overview
of PID control.
First, complete calibration of the analog output used for EZ-
Cool
™
LIOC. Typically, this will be analog output #1 for PID #1.
• Power down the panel and remove the two control
wires for the valve from terminals 1 & 2 of the P11A
terminal strip of analog board #1.
• Place the leads of a calibrated, quality meter to ter
minal one (positive) and terminal two (negative). Set
the meter to read mA DC and power up the panel.
• Set operating session to session [2] and go to the
screen shown in Figure 20 by pressing [Menu] >[Cali-
bration] > [Analog Outputs] > [Output Calibration].
• Press #1 on the keypad to drive the output to the
low end. Using numbers 4, 7 and 0 on the keypad
to increase and decrease the output and change the
“Delta For Changing Output Percentage” setpoint, set
the output to 4mA.
• If the read value is less than the objective of 4 or 20mA
use 7 on the keypad, increase the output by the Delta.
If the read value is more than the objective, use 4 to
decrease the value by the Delta.
• Use the 0 key to change the Delta from 10 to 1, .10
or .01% to tune the output to the objective of 4 or
20mA.
• Press #3 on the keypad to set the output to the high
end and repeat the process in the preceding steps to
set the output to 20mA.
• Power down the panel, remove the meter and recon
nect the control wires for the EZCool LIOC valve as
they were removed to terminals 1 & 2 of the P11A
terminal strip of analog board #1.
Figure 20 - Analog Output Calibration
Description of Proportional Band and Gain setpoints:
• Proportional Band – This setpoint determines the size
of a region either above or below the Control Setpoint.
Within this region the Proportional component of the
PID Output value is the number between 0% and 100%
that directly corresponds to the difference between
the Control Input (Actual) and the Control Setpoint
(Setpoint). Outside of this region the Proportional
component is either 100% or 0%. If the PID Action
is Forward, the Proportional Band extends above the
Control Setpoint. If the PID Action is Reverse, the
Proportional Band extends below the Control Setpoint.
• Proportional Gain  This value is calculated from the
Proportional Band setpoint and is the same value that
was entered as a Proportional Gain setpoint in the
Quantum. The control setpoint will not be achieved
with proportional control only. Integral control is
needed to further correct the control input to achieve
the setpoint.
• Integral Gain  This setpoint controls the inuence the
Integral component exerts on the PID Output value.
The Integral component works to push the Control
Input toward the Control Setpoint by tracking the
difference between the Control Input and the Control
Setpoint over time.
• Derivative Gain  This setpoint controls the inuence
the Derivative component exerts on the PID Output
value. The Derivative component reacts to rapid
changes in the value of the Control Input by predicting
the direction the Control Input is traveling and then
turning it back toward the Control Setpoint.
Example of Proportional Only Control:
Control Input: Discharge Temperature
Control Setpoint: 150°F
Dead Band: 0°F
Proportional Band: 25
Action: Forward

Johnson Controls Frick RWF II Specifications

General

Brand	Johnson Controls
Model	Frick RWF II
Category	Air Compressor
Language	English