Technical Guide for Temperature Controllers

CSM_Temperature_TG_E_6_2

Over View of Temperature Controllers

■ Temperature Control Configuration Example
The following example describes the basic configuration for temperature control.
• Relay output • SSR • Thermocouple
• Voltage output • Cycle Controller • Platinum resistance thermometer
• Current output • Power Controller • Thermistor
Controlled object
Temperature Controller

Control signal Controller

● Temperature Sensor
The Temperature Sensor consists of an element
protected by a pipe. Locate the element, which
converts temperatures into electrical signals, in
places where temperature control is required.

● Temperature Controller ● Controller

A Temperature Controller receives electrical signals A Controller is used to heat or cool furnaces and
input from the Temperature Sensor, compares the tanks using devices such as a solenoid that cuts
electrical signal input to the set point, and outputs off electric current to a heater or a fuel valve that
adjustment signals to the Controller. shuts off the fuel supply.

■ Temperature Control 1. The temperature stabi-

Temperature
lizes after overshoot-
ing several times.
The set point is input to operate the Temperature Controller. The time
required for stable temperature control varies with the controlled
object. Attempting to shorten the response time will usually result in
overshooting or hunting the temperature. The response time must
not be shortened to reduce overshooting or hunting the temperature.
There are applications that require prompt, stable control in the Time
waveform shown in (1) despite overshooting. There are other 2. Proper response

Temperature
applications that require the suppression of overshooting in the
waveform shown in (3) despite the long time required to stabilize the
temperature. In other words, the type of temperature control varies
with the application and purpose. The waveform shown in (2) is
usually considered to be a proper one for standard applications.

Time
3. The response is slow
Temperature

in reaching the set

point.

Time

■ Characteristics of the Controlled Object

Before selecting a Temperature Controller or Temperature Sensor, it is necessary to understand the thermal characteristics of the controlled
object for proper temperature control.

Heat capacity ······· Heat capacity, which indicates the ease of heating, varies with the capacity of the furnace.

Static ······· Static characteristics, which indicate heating capability, vary with the capacity of the heater.
Characteristics characteristics
of the controlled
object Dynamic Dynamic characteristics, which indicate the startup characteristics (i.e. excessive response)
·······
characteristics of heating, vary with heater and furnace capacity that can affect each other in a complex way.

External External disturbances cause temperature changes. For example, the opening or closing of a door on a
·······
disturbances constant temperature tank can cause external disturbances that generate temperature changes.

1
 ON/OFF Control Action I Action
As shown in the graph below, if the process value is lower than the I action (integral control action) is used to obtain an output in
set point, the output will be turned ON and power will be supplied to proportion to the time integral value of the input.
the heater. If the process value is higher than the set point, the output
P action causes an offset. Therefore if proportional control action and
will be turned OFF and power to the heater will be shut off. This
integral control action are used in combination, the offset will be
control method, in which the output is turned ON and OFF based on
reduced over time until the control temperature eventually will
the set point in order to keep the temperature constant, is called ON/
coincide with the set point and the offset will cease to exist.
OFF control action. With this action, the temperature is controlled
using two values (i.e., 0% and 100% of the set point). Therefore, the
operation is also called two-position control action. Offset ceases to exist.

Characteristics of ON/OFF control action Set point

Hysteresis
Set point

PI
Offset (proportional and
integral control) action
P
(proportional control)
action only

Time
Time

Control output
(%)
ON 100
Heater
OFF
50 A short integral time is set.

P Action
0
P action (or proportional control action) is used to obtain an output in A long integral time is set.

proportion to the input. The Temperature Controller in P action has a Time

proportional band with the set point in the proportional band. The A short integral time is set.
control output varies in proportion to deviation in the proportional
band. In normal operation, a 100% control output will be ON if the
Set point
process value is lower than the proportional band. The control output
will be decreased gradually in proportion to the deviation if the
process value is within the proportional band, and a 50% control
A long integral time is set.
output will be ON if the set point coincides with the process value.
(i.e., there is no deviation). This means P action ensures smoother
control with minimal hunting compared with the ON/OFF control Time
action.
D Action
Proportional control action
D action (derivative control action) is used to obtain an output in
Control output

ON
100% proportion to the time derivative value of the input.
Proportional control action corrects the control results as does
50%
integral control action. Therefore, proportional control action and
0%
integral control action respond slowly to temperature change. This is
OFF why derivative control is required. Derivative control action corrects
control results by adding the control output in proportion to the slope
90°C Set point 100°C 110°C Temperature of temperature change. A large control output is applied to radical
Proportional external disturbances to get the temperature quickly back under
band control.
Example: If a Temperature Controller with a temperature range of
PD
0°C to 400°C has a 5% proportional band, the width of the (proportional and
proportional band will be converted into a temperature derivative control) action

range of 20°C. In this case, a full output is kept turned ON Set point
until the process value reaches 90°C, and the output is
OFF periodically when the process value exceeds 90°C, External
disturbance P
provided the set point is 100°C. When the process value is (proportional control)
100°C, there will be no difference in time between the ON action only

period and the OFF period (i.e. the output is turned ON

and OFF 50% of the time.)
Time
A narrow proportional band is set.
Control output
Control output

(%) (%)
100 A wide proportional band is set. 100 A long derivative time is set.

A short derivative time is set.

50 50

0 0

Time
Set point
A long derivative time is set.
A narrow proportional band is set.
Set point
Set point
A short derivative time is set.
Offset

A wide proportional band is set.

Time

Time

2
 PID Control Two PID Control
PID control is a combination of proportional, integral, and derivative Conventional PID control uses a single control block to control the
control actions. The temperature is controlled smoothly here by responses of the Temperature Controller to a target value and to
proportional control action without hunting, automatic offset external disturbances. Therefore, the response to the target value
adjustment is made by integral control action, and quick response to will oscillate due to overshooting if importance is placed on
an external disturbance is made possible by derivative control action. responding to external disturbances with the P and I parameters set
to small values and the D parameter set to a large value in the
control block. On the other hand, the Temperature Controller will not
be able to respond to external disturbances quickly if importance is
placed on responding to the target value (i.e., the P and I parameters
are set to large values). This makes it impossible to satisfy both the
types of response in this case.
Two PID control eliminates this drawback while maintaining the
strengths of PID control. This makes it possible to improve both types
of responses.

PID Control
(1)

PID control

Response to the target value will be slow if response to the

external disturbance is improved.
(2)

Response to the external disturbance will be slow if response to

the target value is improved.

Two PID Control

(3)

Response to target value Response to

external disturbance

Controls both the target value and the external disturbance

response.

3
Temperature Controller Glossary
■ Glossary of Control Terminology
Hysteresis Control Cycle and Time-Proportioning
ON/OFF control action turns the output ON or OFF based on the set Control Action
point. The output frequently changes according to minute
temperature changes as a result, and this shortens the life of the The control output will be turned ON intermittently according to a
output relay or unfavorably affects some devices connected to the preset cycle if P action is used with a relay or SSR. This preset cycle
Temperature Controller. To prevent this from happening, a is called the control cycle and this method of control is called time-
temperature band called hysteresis is created between the ON and proportioning control action.
OFF operations. Actual temperature Example:
Temperature Proportional band
If the control cycle is 10 s
Hysteresis (Reverse Operation) with an 80% control
Hysteresis Set output, the ON and OFF
Control output

point
ON periods will be as
follows.
The higher the temperature is the shorter the ON period will be.

ON TON: 8 s
OFF
OFF
T T T T T T T T TOFF: 2 s
T: Control cycle
TON TON: ON period
MV= ×100(%)
99.2°C 100°C Temperature TON + TOFF TOFF: OFF period

Example: Hysteresis indicates 0.8°C.

Hysteresis (Forward Operation) Derivative Time
Hysteresis
Derivative time is the period required for a ramp-type deviation in
Control output

ON
derivative control (e.g., the deviation shown in the following graph)
that coincides with the control output in proportional control action.
The longer the derivative time is the stronger the derivative control
action will be.
OFF
PD Action and Derivative Time
Derivation

100°C 100.8°C Temperature

0
Example: Hysteresis indicates 0.8°C.
PD action
Offset PD action
(with a short derivative time)

(with a long derivative time)

Proportional control action causes an error in the process value due
to the heat capacity of the controlled object and the capacity of the
Control output

P action
heater. The result is a small discrepancy between the process value
and the set point in stable operation. This error is called offset. Offset D2 action
is the difference in temperature between the set point and the actual
process temperature. It may exist above or below the set point. D1 action

Offset
TD: derivative time
Set point

TD1
(with a short derivative time)
TD2
Proportional Offset (with a long derivative time)
band

ON
OFF

Hunting and Overshooting

ON/OFF control action often involves the waveform shown in the
following diagram. A temperature rise that exceeds the set point after
temperature control starts is called overshooting. Temperature
oscillation near the set point is called hunting. Improved temperature
control is to be expected if the degree of overshooting and hunting
are low.
Hunting and Overshooting in ON/OFF Control Action
Overshooting
Set
point

Hunting

4
Integral Time Limit Cycle Method
Integral time is the period required for a step-type deviation in ON/OFF control begins from start point A in this method. Then obtain
integral control (e.g., the deviation shown in the following graph) to the PID constants from the hunting cycle T and oscillation D.
coincide with the control output in proportional control action. The
shorter the integral time is the stronger the integral action will be. If Oscillation

Set point
the integral time is too short, however, hunting may result. A

PI Action and Integral Time

PI action Hunting cycle
Deviation

(with a short integral time)

0
Time

PI action
(with a long integral time) Readjusting PID Constants
PID constants calculated in auto-tuning operation normally do not
cause problems except for some particular applications. In those
cases, refer to the following diagrams to readjust the constants.
Control output

P action

T11 T1: Integral time

Response to Change in the Proportional Band
(with a short integral time)
Wider It is possible to

Set point
T12 suppress overshooting
(with a long integral time)
although a
comparatively long
Constant Value Control startup time and set
time will be required.
For constant value control, control is preformed at specific
temperatures. Nar- The process value
Set point
rower reaches the set point
Program Control within a comparatively
short time and keeps
Program control is used to control temperature for a target value that the temperature stable
changes at predetermined time intervals. although overshooting
and hunting will result
Auto-tuning until the temperature
becomes stable.
The PID constant values and combinations that are used for
temperature control depend on the characteristics of the controlled Response to Change in Integral Time
object. A variety of conventional methods that are used to obtain
these PID constants have been suggested and implemented based Wider The set point takes
Set point

on actual control temperature waveforms. Auto-tuning methods make longer to reach. It is

it possible to obtain PID constants suitable to a variety of controlling possible to reduce
objects. The most common types of auto-tuning are the step hunting, overshooting,
response, marginal sensitivity, and limit cycle methods. and undershooting al-
though a comparative-
Step Response Method ly long startup time
and set time will be re-
The value most frequently used must be the set point in this method. quired.
Calculate the maximum temperature ramp R and the dead time L Nar- The process tempera-
Set point

from a 100% step-type control output. Then obtain the PID constants rower ture reaches the set
from R and L. point within a compar-
atively short time al-
Set point

though overshooting,
undershooting, and
R hunting will result.

Response to Change in Derivative Time

Wider The process value
Set point

External disturbance
L
reaches the set point
Time
within a comparatively
short time with com-
Marginal Sensitivity Method paratively small
amounts of overshoot-
Proportional control action begins from start point A in this method. ing and undershooting.
Narrow the width of the proportional band until the temperature starts Fine-cycle hunting will
to oscillate. Then obtain the PID constants from the value of the result due to the
proportional band and the oscillation cycle time T at that time. change in process val-
ue.
Nar- The process value will
Set point

External disturbance
Set point

A
rower take a relatively long
TC
time to reach the set
point with heavy over-
shooting and under-
shooting.
Marginal sensitivity method
Time

5
 Fuzzy Self-tuning Self-tuning
PID constants must be determined according to the characteristics of Self-tuning is supported by the E5@S. Trends in temperature
the controlled object for proper temperature control. The changes are used to automatically calculate and set a suitable
conventional Temperature Controller incorporates an auto-tuning proportional band.
function to calculate PID constants. In that case, it is necessary to
give instructions to the Temperature Controller to trigger the auto-
tuning function. Furthermore, temperature disturbances may result if Set point
the limit cycle is adopted. The Temperature Controller in fuzzy self-
tuning operation determines the start of tuning and ensures smooth
tuning without disturbing temperature control. In other words, the
fuzzy self-tuning function makes it possible to adjust PID constants
according to the characteristics of the controlled object.
Time
Self-tuning
Fuzzy Self-tuning in 3 Modes
• PID constants are calculated by tuning when the set point changes.
• When an external disturbance affects the process value, the PID
PID Control and Tuning Methods for
constants will be adjusted and kept in a specified range. Temperature Controllers
• If hunting results, the PID constants will be adjusted to suppress
hunting. Model PID Two PID Two PID + Fuzzy
Type of PID
Auto-tuning with a Conventional Temperature Controller E5@N (See note.) AT, ST**
Auto-tuning (AT) Function: A function that automatically calculates E5@S ST*
optimum PID constants for controlled objects.
Features: (1) Tuning will be performed when the AT instruction is given. E5ZN AT
(2) The limit cycle signal is generated to oscillate the E5ZD AT AT
temperature before tuning. C200H-TC AT
Target value C200H-TV AT
C200H-PID AT
Temperature PID gain
AT starts oscillated. calculated. CQM1-TC AT

ST: Fuzzy self-tuning, ST*: Self-tuning, ST**: Executed only for SP changes,
AT instruction
AT: Autotuning
Note: Not including the E5ZN
Self-tuning
Self-tuning (ST) Function: A function that automatically calculates
optimum PID constants for controlled objects.
Features: (1) Whether to perform tuning or not is determined by the
Temperature Controller.
(2) No signal that disturbs the process value is generated.
External External
disturbance 1 disturbance 2
Target value

PID gain Temperature Temperature

calculated. in control in control

ST starts

Control Outputs

Relay output Contact relay output used for control methods with comparatively low switching
frequencies.

ON/OFF output SSR output Non-contact solid-state relay output for switching 1 A maximum.

ON/OFF pulse output at 5, 12, or 24 VDC externally connected to a

Voltage high-capacity SSR. ON/OFF action is ideal for high switching frequency and
Control output PID action is ideal for time-proportioning control action.
output
Continuous 4- to 20-mA or 0- to 20-mA DC output used for driving power
Current controllers and electromagnetic valves. Ideal for high-precision control. A preset
output linear output is produced if the load resistance falls below allowable levels.
Linear output
Voltage Continuous 0 to 5 or 0 to 10 VDC output used for driving pressure controllers.
output Ideal for high-precision control.

6
■ Glossary of Alarm Terminology
Alarm Operation Heater Burnout Alarm
The Temperature Controller compares the process value and the (Three phase (E5CN, E5AN, and E5EN only) and single phase)
preset alarm value, turns the alarm signal ON, and displays the type
Many types of heaters are used to raise the temperature of the
of alarm in the preset operation mode.
controlled object. The CT (Current Transformer) is used by the
Temperature Controller to detect the heater current. If the heater's
Deviation Alarm power consumption drops, the Temperature Controller will detect
heater burnout from the CT and will output the heater burnout alarm.
The deviation alarm turns ON according to the deviation from the set

Current value
point in the Temperature Controller.
Heater burnout
Setting Example A Heater burnout alarm setting

Alarm temperature is set to 110º. Alarm set point

10°C
The alarm set point is set to 10°C. 0 T

Set point (SV) Alarm value

100°C 110°C

Absolute-value Alarm Heater current waveform (CT waveform)

The absolute-value alarm turns ON according to the alarm

temperature regardless of the set point in the Temperature
Controller. The wires connected
to the Temperature
Setting Example Current Controller have no
Transformer (CT) polarity.
Alarm set point
Alarm temperature is set to 110°C.
The alarm set point is set to 110°C.
Control output
Set point (SV) Alarm value
100°C 110°C
Heater

Standby Sequence Alarm Switch

It may be difficult to keep the process value outside the specified Alarm Latch
alarm range in some cases (e.g., when starting up the Temperature
The alarm will turn OFF if the process value falls outside alarm
Controller), and the alarm turns ON abruptly as a result. This can be
operation range. This can be prevented if the process value enters
prevented with the standby sequential function of the Temperature
the alarm range and an alarm is output by holding the alarm output
Controller. This function makes it possible to ignore the process
until the power supply turns OFF.
value right after the Temperature Controller is turned ON or right
after the Temperature Controller starts temperature control. In this Upper limit
case, the alarm will turn ON if the process value enters the alarm alarm setting
range after the process value has been once stabilized.
Set point
Example of Alarm Output with Standby Sequence Set
Temperature rise
Upper limit
alarm setting ON
Alarm setting
OFF
Set point

Lower-limit LBA
alarm setting
ON (Applicable models: E5CN, E5AN, and E5EN)
Alarm output
OFF The LBA (loop break alarm) is a function that turns the alarm signal
Temperature Drop
ON by assuming the occurrence of control loop failure if there is no
input change with the deviation above a certain level. Therefore, this
Upper limit function can be used to detect control loop errors.
alarm setting

Set point
Configurable Upper and Lower Limit
Lower-limit
Alarm Settings
alarm setting
(Applicable models: E5@N and E5@R)
ON
Alarm output
OFF L H

SSR Failure Alarm SP

(Applicable models: E5CN)

The SSR Failure Alarm is output when an SSR short-circuit failure is
detected. A CT (Current Transformer) is used by the Temperature
Controller to detect heater current and it outputs an alarm when a
short circuit occurs.

7
■ Glossary of Temperature Sensor Terminology
Cold Junction Compensation Input Shift
The thermo-electromotive force of the thermocouple is generated due to
A preset point is added to or subtracted from the temperature
the temperature difference between the hot and cold junctions.
detected by the Temperature Sensor of the Temperature Controller to
Therefore, if the cold junction temperature fluctuates, the thermo-electromotive
display the process value. The difference between the detected
force will change even if the hot junction temperature remains stable.
temperature and the displayed temperature is set as an input
To negate this effect, a separate sensor is built into the Temperature Controller at
compensation value.
a location with essentially the same temperature as the cold junction to monitor
any changes in the temperature. A voltage that is equivalent to the resulting
thermo-electromotive force is added to compensate for (i.e., cancel) changes that
occur in the thermo-electromotive force.
Compensation for fluctuations by adding a voltage is called cold
110°C
junction compensation.
Furnace
Terminal 20°C

Sensing point
350°C VT Temperature 120°C
Controller

Cold junction compensating circuit Input compensation value: 10°C (Displayed value is 120°C.)
(120 − 110 = 10)

In the above diagram, the When the ambient (terminal section) temperature is
thermo-electromotive 20°C, the temperature sensor inside the Temperature
force (1) VT that is Controller detects 20°C. If we add the voltage V(20, 0)
that corresponds to 20°C in the standard electromotive
measured at the input force table to the right side, we get the following:
terminal of the
Temperature Controller is V(350, 20) + V(20, 0)

equal to V (350, 20).

Thermo-electromotive Electromotive force generated
Here, V (A, B) gives the force from thermocouple by the cold junction
thermo-electromotive compensation circuit
force when the cold
junction is A °C and the If we expand the first part of formula (2) with
A = 350, B = 20, and C = 0, we get the following:
cold junction is B °C. = V{(350, 0) − V(20, 0)} + V(20, 0) = V(350, 0).
Based on the law of
V(350, 0) is the thermo-electromotive force for a cold
intermediate temperatures, junction temperature of 0°C. This is the value that is
a basic behavior of defined as the standard thermo-electromotive force
thermocouples, (2) V (A, by JIS, so if we check the voltage, we can find the
temperature of the hot junction (here, 350°C).
B) = V (A, C) - V(B, C).

Compensating conductor
An actual application may have a sensing point that is located far
away from the Temperature Controller.
If normal copper wires are used because the wiring length is limited
for a sensor that uses thermocouple wires or because conductors
are too expensive, a large error will occur in the temperature.
Compensating conductors are used instead of plain wires to extend
the thermocouple wires.
If compensating conductors are used within a limit temperature
range (often near room temperature), a thermo-electromotive force
that is essentially the same as the original thermocouple is
generated, so they are used to extend the thermocouple wires.
However, if compensating conductors that are suitable for the type of
thermocouple are not used, the measured temperature will not be correct.
Connection
terminal Compensating Terminal
conductor

20°C

350°C 30°C Temperature

Controller

V (350, 30) + V (30, 20) + V (20, 0)

Thermo- Thermo- Voltage from
electromotive electromotive cold junction
force from force from compensation
thermocouple compensating
conductors
= {V (350, 30) - V (30, 0)} + {V(30, 0) - V (20, 0)} + V (20, 0)
= V (350, 0)
Example of Compensating Conductor Use

8
■ Glossary of Output Terminology
Reverse Operation (Heating) Rate of Change Limit
The Temperature Controller in reverse operation will increase control
The rate of change limit for the MV sets the amount of change that
output if the process value is lower than the set point (i.e., if the
occurs per second in the MV. If the MV calculated by the
Temperature Controller has a negative deviation).
Temperature Controller changes significantly, the actual output
follows the rate of change limiter setting for MV until it approaches
Control output (%)

100 the calculated value.

Output (%)
100

Rate of
0
change
1s limit setting
Low Set point High

0
Direct Operation (Cooling) Time
Change point
The Temperature Controller in normal operation will increase control
output if the process value is higher than the set point (i.e., if the
Temperature Controller has a positive deviation).
Dead Band
The overlap band and dead band are set for the cooling output. A
Control output (%)

100 negative value here produces an overlap band and a positive value
produces a dead band.

Output Dead band:

Dead band width: Positive

Low Set point High

Heating Cooling
Heating and Cooling Control output output
PV
0
Temperature control over a controlled object would be difficult if Target value
heating was the only type of control available, so cooling control was
also added. Two control outputs (one for heating and one for cooling) Output Overlap Band:
can be provided by one Temperature Controller. Dead band width: Negative

Temperature Heating
Controller in Controlled
heating and Cooling object
cooling Heating Cooling
control
output output
PV
Heating and Cooling Outputs 0
Target value
Output Output
Cooling Coefficient
When adequate control characteristics cannot be obtained using the
Heating Cooling Heating Cooling same PID constants, such as when the heating and cooling
output output
PV
output output
PV
characteristics of the controlled object vary significantly, adjust the
0 0
Target value Target value proportional band on the cooling side (cooling side P) using the
cooling coefficient until heating and cooling side control are
MV (Manipulated Variable) Limiter balanced. P on the heating and cooling control sides is calculated
from the following formula.
The upper and lower limits for the MV limiter are set by the upper MV
and lower MV settings. When the MV calculated by the Temperature Heating side P = P
Controller falls outside the MV limiter range, the actual output will be
Cooling side P = Heating side P x cooling coefficient
either the upper or lower MV limit.
For cooling side P control when heating side characteristics are
Output (%)

100 different, multiply the heating side P by the cooling coefficient.

Upper MV limit

Heating Side P × 0.8

Output

Lower MV limit
0
Heating side
PV P × 1.0
With heating and cooling control, the cooling MV is treated as a
negative value. Generally speaking then, the upper limit (positive Heating Cooling
side P side P
value) is set to the heating output and the lower limit (negative value) 0
PV
is set to the cooling output as shown in the following diagram.
Heating Side P × 1.5
Output (%)

Output

100 Heating side P × 1.0

Upper MV limit

Lower MV limit
Heating Cooling
Heating Cooling side P
output output side P
0
0 PV PV
Target value

9
Positioning-Proportioning Control Transfer Output
This is also called ON/OFF servo control. When a Control Motor or A Temperature
Modutrol Motor with a valve is used in this control system, a Controller with current
Temperature
potentiometer for open/close control reads the degree of opening output independent Controller with
(position) of the control valve, outputs an open and close signal, and from control output is transfer output
transmits the control output to Temperature Controller. The available. The process
Temperature Controller outputs two signals: an open and close value or set point
signal. OMRON uses floating control. This means that the within the available
potentiometer does not feed back the control valve position and temperature range of Recorder
temperature can be controlled with or without a potentiometer. the Temperature
Controller is Temperature Sensor
converted into 4- to
20-mA linear output 20 mA

Temperature Open that can be input into

output
Controller in recorders to keep the 12 mA
Controlled
position- M object results of temperature
proportioning
control
control on record.
Close
4 mA

Potentiometer 0°C 100 200

reading the Process value
Lower limit Upper limit
control valve
position

■ Glossary of Setting Terminology

Set Limit Set Point (SP) Ramp
The set point range depends on the Temperature Sensor and the set The SP ramp function controls the target value change rate with the
limit is used to restrict the set point range. This restriction affects the variation factor. Therefore, when the SP ramp function is enabled,
transfer output of the Temperature Controller. some range of the target value will be controlled if the change rate
exceeds the variation factor as shown on the right.
−200°C 1300°C K
SP
SP ramp
Target value
after changing
0°C 500°C
Possible setting range SP ramp
set value
SP ramp
Multiple Set Points Target value
before changing
time unit

Time
Two or more set points independent from each other can be set in Change point
the Temperature Controller in control operation.
Remote Set Point (SP) Input
Setting Memory Banks
For a remote set point input, the Temperature Controller uses an
The Temperature Controller stores a maximum of eight groups of external input ranging from 4- to 20-mA for the target temperature.
data (e.g., set value and PID constant data) in built-in memory banks When the remote SP function is enabled, the 4- to 20-mA input
for temperature control. The Temperature Controller selects one of becomes the remote set point.
these banks in actual control operation.
Memory Bank 00 Event Input
Set value Bank 1
P constant An event input is an external signal that can be used to control
I constant Bank 7
various actions, such as target value switching, equipment or
D constant
process RUN/STOP, and pattern selection.

Input Digital Filter

The input digital filter parameter is used to set the time constant of
the digital filter. Data that has passed through the digital filter
appears as shown in the following diagram.
Select bank 1.
PV before passing through the filter

Temperature control using PV after passing through the filter

constants in memory bank 1

0.63 A

(Time Time
constant)
Input digital filter

10
Precautions for Correct Use of Temperature Controllers
For the precautions for individual products, refer to the Safety Precautions for that product.

■ Correct Use Operating Precautions

1. It takes up to 5 s for the outputs to turn ON after the power supply
Service Life is turned ON. Take this time into consideration when the
Temperature Controller is incorporated in a sequence circuit.
Use each product within the range of specifications for that product. 2. When using the self-tuning function of the E5@N, turn ON the
When the Temperature Controller is incorporated in a control panel, Temperature Controller and load (e.g., heater) simultaneously or
make sure that the Controller’s ambient temperature and not the turn ON the load before the Temperature Controller. If the load is
ambient temperature of the control panel does not exceed the turned ON after the Temperature Controller, correct self-tuning
specified temperature range. and optimum control will not be possible. When starting operation
after the Temperature Controller has warmed up, turn OFF the
The service life of the Temperature Controller and other electronic
power supply and then turn it ON again at the same time as
devices is determined not only by the number of times the relays are
turning ON the power supply for the load. (Instead of turning the
switched, but also by the service life of internal electronic
Temperature Controller OFF and ON again, switching from STOP
components. Component service life is affected by the ambient
mode to RUN mode can also be used.)
temperature: the higher the temperature, the shorter the service life,
and the lower the temperature, the longer the service life. Therefore, 3. Using the Temperature Controller near radios, televisions, or
the service life can be extended by lowering the temperature of the wireless devices may cause reception interference.
Temperature Controller.
Mounting two or more Temperature Controllers side by side, or
mounting Temperature Controllers one above another may cause
heat to build up inside the Temperature Controllers, which will shorten
their service life. If the Temperature Controllers are mounted one
above another or side by side, use forced cooling by fans or other
means of air ventilation to cool the Temperature Controllers. Be sure
not to cool only the terminals. Otherwise, measurement errors may
occur.

Ensuring Measurement Accuracy

When extending or connecting the thermocouple lead wires, be sure
to use compensating wires that match the thermocouple type.
When extending or connecting the lead wire of the platinum
resistance thermometer, be sure to use wires that have low resistance
and keep the resistance of the three lead wires the same.
Make sure that the temperature sensor type and the input type of the
Temperature Controller are the same.
There are two types of platinum resistance thermometer: Pt and JPt.
Correct measurement will not be possible if the input type of the
Temperature Controller is incorrect.
Mount the Temperature Controller so that it is horizontally level.
If the measurement accuracy is low, check that to see if the input shift
has been set correctly.

Waterproofing
Models for which the degree of protection is not specified and models
with IP@0 degree of protection do not have waterproof specifications.

EN/IEC Standards
If the Temperature Controller is to conform to EN/IEC standards, it is
recommended to install the following fuse in the power supply
terminal section.
Recommended fuse: T2A, 250-VAC, time-lag fuse with low breaking
capacity

ALL DIMENSIONS SHOWN ARE IN MILLIMETERS.

To convert millimeters into inches, multiply by 0.03937. To convert grams into ounces, multiply by 0.03527.

In the interest of product improvement, specifications are subject to change without notice.

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