red lion PXU10020, Instructions Manual

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Drawing No. LP0932 Released 2018-01-12
Setpoint Profile Operation
PROFILE OVERVIEW
The PXU can be configured for ramp/soak profile operation, where the
unit can control a process to conform to a time based process/
temperature profile. A profile is a series of 1 to 16 programmable ramp or
hold (soak) segments. Each segment has a setpoint value and segment
duration time value associated with it. The segment type, i.e., ramp or
hold (soak) segment, is determined by whether or not the previous
segment’s setpoint is the same as the preceding setpoint. If they differ,
the segment setpoint value will ramp from the previous setpoint value to
the preceding segment’s setpoint value within the programmed segment
time. The segment time effectively controls the ramp rate. When a profile
is started, each time based segment will execute in order until the
completion of the last segment, at which point the profile will cycle, end
or link to another profile. There are 16 profiles, which may be linked to
increase the number of segments used for a process. Each profile can
be started, stopped, paused or automatically delayed to insure profile
conformity (guarantied soak). Each profile has its own parameter for the
number of profile segments to run (
Nd
#), number of times to cycle the
profile (
CYCx
), and profile link/termination (
L1Nx
).
SETPOINT PROFILE CONFIGURATION
The PXU’s factory setting is basic process PID control to a single
setpoint. When the PXU is to be used for setpoint profile operation, the
Setpoint Control Mode parameter,
StPt
in Module 2-OP is set to setpoint
profile mode (
StPt
=
Po
). There are several Line 2 display parameters
associated with profile operation and status that can be enabled for use
in the various display loops of the PXU. These Line 2 display parameters
are, the Profile Status (
PSt
), Profile Segment Time Remaining (
t1
), the
Controller Status parameter (
S
) and the Active Profile parameter (
Po
).
The Profile Status Line 2 parameter (
PSt
), indicates the current profile
and segment number as well as it’s current run state; i.e., running,
paused, ended/stopped, or automatically delayed to insure profile
conformity (guaranteed soak). The Controller Status parameter,
S
, can
be used to start, pause, end the profile, or stop PID control and the
profile.
SETPOINT PROFILE OPERATING MODES
Profile Run Mode
The controller is in the run mode while a profile is executing. While in
the run mode, the profile can be stopped (End/Stop Mode), paused
(Pause Mode), automatically delayed (to insure process conformity, i.e,
Delay Mode) or advanced to the next phase. A profile is started and
placed into the run mode either manually or when powered down in run
mode.
Profile End/Stop Mode
The End/Stop Mode signifies that profile progress has stopped. The
profile End/Stop Mode is achieved by manually terminating a profile in
progress or by allowing a profile to run to completion. The profile can be
configured to end and maintain the profile’s last segment setpoint value
(
P
) or end and disable PID control (
StP
). If the profile end mode is
manually terminated and the end action is to maintain the last setpoint
value, the controller will control to the actual setpoint value, ramping or
hold, at the instant of termination.
Profile Pause Mode
The pause mode signifies that a profile is active but the time base is
currently stopped (paused). The pause mode is caused only by a manual
action via user input, function key or Controller Status parameter (
S
).
Pausing a profile during a ramp segment pauses the ramp/profile timer,
and the controller maintains the actual setpoint value at the instant of the
pause action. If a profile is paused during a hold segment, the timing of
the hold segment is paused. The use of pause mode effectively
lengthens the total run time of a profile.
Delay Mode
Delay Mode indicates that a profile is active but the time base, or
profile advancement is stopped. This is caused by automatic action of
the controller when the process value varies more than the amount,
specified by the Deviation Error Value, parameter, Er-V, from the profile
setpoint. Delay Mode is similar to the pause mode, except the delay
mode is invoked and revoked automatically by the controller. Delay Mode
is applied when the process value is below [PV < (SP – Er-V)] or above
[PV > (SP + Er-V)] the setpoint. The profile automatically resumes timing
when the process value is within the prescribed error band value. The
Delay Mode is indicated by a ‘d’ in the first digit of the Profile Status line
2 Parameter,
PSt
. The Delay Mode can be terminated manually by
changing the deviation error parameter,
Er-V
to a larger value. The
change takes effect immediately. Delay Mode is disabled by setting the
Profile Error Band parameter,
Er-V
, to 0.
Error Band Delay Mode Timeout
When profile Delay Mode is activated, a timer will start. If the profile
remains in Delay Mode and the timer reaches the Error Band Timeout
value,
t
, the Profile Error Band Timeout flag,
Pt
, is set. A
t
value
of 0 disables this action. If available, an Alarm can be configured to
activate when the Profile Error Band Timeout flag is set. See the Alarms
configuration module,
L
.
PAUSE
TEMPERATURE
TIME
RUN
OPERATION
OFF
PAUSE
OPERATION
RUN
OPERATION
PROFILE
STATUS
PROFILE
PAUSED
PROFILE
PAUSED
PAUSE
OPERATION
RUN
OPERATION
PAUSE
RAMP
SEGMENT
RESUME
RAMP
SEGMENT
HOLD
SEGMENT
RESUME
HOLD
SEGMENT
r
^
01 r
^
01 r-02 r-02 P
^
01 P-02
  
  
PCS
RAMP 1
TEMPERATURE
TIME
START
OPERATION
OFF
PROFILE
STATUS
DELAY
MODE
RESUMES
RAMP 1
DELAY
MODE
HOLD 1
HOLD 1
RESUMES
ERROR BAND
PROFILE
SETPOINT
PROCESS
TEMPERATURE
r
^
01 r
^
01 r-02 r-02 d
^
01 d-02 PCS
PROFILE PAUSE MODE
PROFILE DELAY MODE