IM 05C01E12-41E
18
■ Description of Parameters
This section describes the parameter functions specific to the UT150/UT152/UT155 temperature controllers.
(The functions described in other sections of this manual and the general functions are not discussed.)
Parameter Function Parameter Function
Control mode
CTL
Select one from the following:
a. Dynamic auto tune control (SLF)
(See note)
b. PID control (PID)
c. On/off control (ONF)
Note: Dynamic auto tune control is not available
for heating/cooling control.
Read the section below this table to find out more
about dynamic auto tune control.
PV input bias
BS
This function adds a bias value to the measured input value,
and the result is used for display and control computation.
This function is useful for carrying out fine adjustment when
the PV value is within the required accuracy but it differs
from the value obtained by other equipment.
Manual reset
MR
You can set this parameter only for control
without an integral action (when registered as
CTL=PID and I=OFF). The controller outputs the
manual reset (MR) value when PV=SP. For
example, if you set MR=50%, the controller
outputs (OUT) 50% when PV=SP.
Cooling-side
gain
COL
Maximum/minimum
value of
measured
input scale
RH,
RL
For heating/cooling control, you can set the ratio
between the cooling-side output and heating-side
output.
For example, if you set COL=2.0 and the heating-
side output is 10% at a certain deviation (SP-PV),
then the cooling-side output will be 20% when the
cooling-side also reaches that deviation.
Deadband
DB
You can only set a deadband for heating/cooling
control. In a positive deadband, there are neither
heating-side nor cooling-side outputs. In a
negative deadband, there are both heating-side and
cooling-side outputs, which overlap each other.
Maximum/minimum
value of
target setpoint range
SPH,
SPL
Using the SPH and SPL parameters, you can limit
the setting range of the target setpoint (SP) within
the measured input range(scale).
This function prevents SP from being mistakenly
set at too large or too small a value (beyond the
setting range).
Hysteresis for
on/off control
HYS
For on/off control (CTL=ONF), you can set a
hysteresis around the on/off point (SP) to prevent
chattering.
Setpoint ramp
up/ramp-down
rate
UPR,
DNR
To prevent a sudden change in SP, or to change SP at a
constant rate, ramp-up and ramp-down rates can be set
separately. This function operates at the following events.
a. SP change
b. SP1/SP2 switching
c. Power-on
At power-on, SP starts from
the current PV value.
Set the ramp-rate time unit using parameter TMU.
The cycle time is the period of on/off repetitions
of a relay or voltage pulse output in time
proportional PID control. The ratio of the ON time
to the cycle time is proportional to the control
output value.
Hysteresis for
alarm 1 and 2
HY1,
HY2
The alarms are output as relay outputs. Since a
relay has a limited life, excessive on/off actions
will shorten the life of the alarm. To prevent this,
you can set a hysteresis to prevent excessive
on/off actions for both alarm 1 and alarm 2.
PV input filter
FL
This function should be used when the PV display value
may fluctuate greatly, for example, when the measured
input signal contains noise. The filter is of the first-
order lag type, and FL sets the time constant. If a larger
time constant is set, the filter can remove more noise.
SUPER
function
selection
SC
The SUPER function is effective in the following cases:
a. An overshoot must be suppressed.
b. The rise-up time needs to be shortened.
c. The load often varies.
d. SP is changed frequently.
Note 1: The SUPER function will not work when
on/off control is selected, or I or D
constants is set at OFF in PID control.
Note 2: For some types of systems, the SUPER
function may not be so useful. If this is
the case, turn off the function.
Decimal point
of measurement
input
DP
For DC voltage input, the input signal can be scaled for the
particular engineering unit. For example, if you set the input
type (IN) at range code 22, the initial range is 0.0 to 100.0.
a.
Using DP, set the decimal point position fit for the
engineering unit you want to use. (In the example below,
the 2 digits to the right of the decimal point)
b.
Next, register the scale values of the measured input scale using
RH and RL. (In the example below, RH=10.00 and RL=0.00)
Initial scale
100.0 (5V)0.0 (1V)
10.00 (RH)0.00 (RL)
Measured input scale
(after being scaled)
R
egister the decimal point position using DP.
On/off point (SP)
Hysteresis
ON
OFF
Cycle time
t ON
t OFF
Input
HYS HYS
ON
OFF
ON
OFF
Deadband
DB (+)
Deadband
DB (+)
0SP
PV
100%
1000SP
100
PV
100%
Cooling
side
Heating
side
100%
0%
1.
When the deadband of a heating/
cooling type is positive
(Proportional band [P] control)
2.
When both the heating and cooling
sides are under on-off control
PV value inside the controller
measured input value
PV bias+=
Ramp-rate
for n°C/min.
or n°C/h.
Control output
/ cooling-side
control output
cycle time
CT
CTC
2-seconds filter
10-seconds filter
To Next Page
Loading...
Need help?
General
