Akytec TRM202 User manual

akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] ·www.akytec.de
TRM202
2-channel controller
User guide
TRM202_2017.04_0239_EN
© All rights reserved
Subject to technical changes and misprints

akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] · www.akytec.de
1
Contents
1Overview..........................................................................................................................................................3
1.1 Documentation ..........................................................................................................................................3
1.2 Functions...................................................................................................................................................3
1.3 RS485 network..........................................................................................................................................3
1.4 Ordering information .................................................................................................................................4
2Specifications .................................................................................................................................................5
2.1 Environmental conditions ..........................................................................................................................6
3Safety...............................................................................................................................................................7
3.1 Intended use..............................................................................................................................................7
4Installation.......................................................................................................................................................8
4.1 Requirements ............................................................................................................................................8
4.2 Mounting....................................................................................................................................................8
5Wiring ..............................................................................................................................................................9
5.1 General......................................................................................................................................................9
5.2 Inputs.......................................................................................................................................................10
5.2.1 Linear signals...................................................................................................................................10
5.3 Outputs....................................................................................................................................................11
5.3.1 Relay output (R)...............................................................................................................................11
5.3.2 NPN transistor (T) ............................................................................................................................11
5.3.3TRIAC (C) ........................................................................................................................................11
5.3.4 Solid state relay (S)..........................................................................................................................12
5.3.5 Analog 4-20 mA (I)...........................................................................................................................12
5.3.6Analog 0-10 V (U) ............................................................................................................................12
6Operation.......................................................................................................................................................14
6.1 Control elements .....................................................................................................................................14
6.2 Principle of operation ..............................................................................................................................15
6.3 First start up ............................................................................................................................................15
7Configuration ................................................................................................................................................17
7.1 Temperature sensor................................................................................................................................17
7.2 Linear signal............................................................................................................................................17
7.2.1 Square root function.........................................................................................................................18
7.3Correction................................................................................................................................................18
7.4 Filter ........................................................................................................................................................19
7.5 Control Unit .............................................................................................................................................20
7.6 Setpoint limits ..........................................................................................................................................20
7.7 Digital output ...........................................................................................................................................20
7.8 Analog output ..........................................................................................................................................22
7.8.1 P control...........................................................................................................................................22

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7.8.2 Signal retransmission.......................................................................................................................23
7.8.3 Output safe state..............................................................................................................................23
7.9 Display settings .......................................................................................................................................23
7.10 RS485 network settings.......................................................................................................................23
7.11 Access protection ................................................................................................................................24
7.12 Factory settings ...................................................................................................................................24
7.13 Calibration............................................................................................................................................24
8Control modes ..............................................................................................................................................25
8.1 General....................................................................................................................................................25
8.2 Automatic control.....................................................................................................................................25
8.3 Control over Network ..............................................................................................................................25
8.4 Errors.......................................................................................................................................................26
9Maintenance..................................................................................................................................................27
10 Transportation and storage.........................................................................................................................28
11 Scope of delivery..........................................................................................................................................29
Appendix A Dimensions ...................................................................................................................................30
Appendix B Configuration parameters............................................................................................................31
Appendix C Modbus access.............................................................................................................................36
Appendix D Error causes and remedies .........................................................................................................40

Overview
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1 Overview
This guide describes the functions, system configuration, operating instructions, pro-
gramming and troubleshooting of the 2-channel controller TRM202 (hereinafter referred
to as TRM202, device, or controller).
1.1 Documentation
Data sheet (PDF document to download)
Data sheet contains general information, ordering information and the technical data
needed for purchase decision.
Short guide (PDF document to download / printed document in the box)
Short guide contains the most important information about installation, wiring, configura-
tion and operation of the device.
User guide (PDF document to download)
User guide contains the complete information about the device.
Modbus access (PDF document to download / printed document in the box)
The document contains the information about the Modbus functions and the Modbus
register allocation of the device.
All PDF documents can be downloaded from www.akytec.de.
1.2 Functions
The 2-channel controller TRM202 is designed for creating automatic control and regula-
tion systems of various technological processes in different areas of industry, agriculture
and utilities.
The controller provides following basic functions:
– measuring of the process value and its transformation according to the sensor type
– displaying the process values and configuration parameters on two 4-digit LED dis-
plays
– scaling and filtering of input signal
– signal correction, square root function
– calculation of the difference between two signals
– independent ON/OFF control of two process variables or three-step control of one
process variable
– automatic control
– network control (RS485 interface) with akYtec, Modbus-RTU and Modbus-ASCII
protocols as a Slave
– signal retransmission using analog output 4-20 mA or 0-10 V
– alarm output
– sensor / input error detection
– error indication
– configuration via the functional keys
1.3 RS485 network
The TRM202 uses the common standard RS485 for data exchange.
Serial interface RS485 enables communication via two-wired line in half-duplex mode.
The device supports the Modbus RTU, Modbus ASCII and akYtec protocols with auto-
matic protocol detection.

Overview
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The network consists of a Master device and can contain up to 32 Slave devices. Maxi-
mum length is 1200 m. The number of Slave devices and network length can be in-
creased by using RS485 interface repeater.
Devices are connected to a network according to linear (bus) topology. It means that the
line goes from the first device to the second one, from the second one to the third one,
etc. Star connection and spur lines are not allowed.
Line reflections always occur at each of the two ends of the bus (the first and the last
node). The higher the data transmission rate, the stronger the reflections are. A terminat-
ing resistor is needed to minimize reflections. 150 ohm (0.5 W) resistor can be used as a
line termination.
The TRM202 can only be used as a Slave device. PLC, computer with SCADA software
or device can be used as a Master device. To connect TRM202 to PC the interface con-
verter IC4 from akYtec can be used.
To establish the communication via Modbus see sections 7.10, 8.3.
1.4 Ordering information
The TRM202 can be ordered in different variants depending on the required housing and
output type.
Housing:
H1 - panel mount (96 x 96 x 70 mm)
H2 - panel mount (96 x 48 x 100 mm)
H3 - wall mount (105 x 130 x 65 mm)
Outputs:
R - Relay *
T - NPN transistor *
C - TRIAC *
S - Solid state relay *
I - 4-20 mA
U - 0-10 V
* For three-step control the device should be equipped with two digital outputs.

Specifications
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2 Specifications
Table 2.1 General Specifications
Power supply
230 (90…245) V AC, 50 (47…63) Hz
Power consumption, max.
6 VA
Analog inputs
2
Input resistance
4
-20 mA
external resistor R
IN
= 100 ohm
(in parallel)
0-1 V
≥ 100 kohm
Optional output
2
Sampling rate, max.
1 s
RS485 interface
Terminals
D+, D-
Protocols
Modbus RTU/ASCII, akYtec
Baud rate
2.4…115.2 kbit/s
Cable
Shielded twisted pair (STP)
Enclosure
H1
H2
H3
Dimension, mm
96 x 96 x 70
96 x 48 x 100
105 x 130 x 65
IP Code
front IP54
front IP54
IP44
Table 2.2 Linear signals
Signal type Measurement range, % Accuracy, %
0-1 V
0…100
±0.5
-50…+50 mV
0…100
0-5 mA
0…100
0-20 mA
0…100
4-20 mA
0…100
Table 2.3 Temperature sensors
Signal type Measurement range, °C
Temperature
coefficient, °C
-1
Accuracy, %
RTD according to IEC 60751:2008
Pt50
-200…+750
0.00385 ±0.25
Pt100
-200…+750
RTD according to GOST 6651
50P
-200...+750
0.00391
±0.25
50M
-190…+200
0.00428
Cu50
-50…+200
0.00426
100P
-200...+750
0.00391
100M
-190…+200
0.00428
Cu100
-50…+200
0.00426
53M
-50…+200
0.00426
46P
-200…+750
0.00391
TC according to IEC 60584-1:2013
J
-200…+1200
-
±0.5
N
-200…+1300
-
К
-200…+1300
-
S
0…+1750
-
R
0…+1750
-
A
0…+2500
-
T
-200…+400
-
B
+200…+1800
TC according to GOST 8.585
L
-200…+800
-
±0.5
A-2
0…+1800
-
A-3
0…+1800
-

Specifications
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Table 2.4 Optional outputs
Ordering
code
Output type Loading capacity
R
Relay
8 A / 230 V AC, cos φ≥ 0.4/ 30 V DC
T
NPN transistor
200 mA, 40 V DC
C TRIAC
50 mA, 240 V AC (constant operation)
500 mA (f ≤50 Hz, pulse duration ≤ 5 ms)
S Solid state relay 100 mA, 4…6 V DC
I
4-20 mA
10…36 V, max. 1 kohm
U
0-10 V
15…36 V, min. 2 kohm
2.1 Environmental conditions
The device is designed for natural convection cooling that should be taken into account
when choosing the installation site.
The following environment conditions must be met:
−clean, dry and controlled environment, low dust level
−closed non-hazardous areas, free of corrosive or flammable gases
Table 2.5
Conditions Permissible range
Ambient temperature
+1…+50°C
Storage temperature
-25…+55°C
Relative humidity
up to 80% (at +35°C, non-condensing)
Altitude
up to 2000 m above sea level

Safety
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3 Safety
Explanation of the symbols and keywords used:
DANGER
DANGER indicates an imminently hazardous situation which, if not avoided, will
result in death or serious injury.
WARNING
WARNING indicates a potentially hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION
CAUTION indicates a potentially hazardous situation which, if not avoided, could
result in minor or moderate injury
►
NOTICE
NOTICE indicates a potentially harmful situation which, if not avoided, may result in
damage of the product itself or of adjacent objects.
3.1 Intended use
The device has been designed and built solely for the intended use described in this
guide, and may only be used accordingly. The technical specifications contained in this
guide must be observed.
The device may be operated only in properly installed condition.
Improper use
Any other use is considered improper. Especially to note:
– This device should not be used for medical devices which receive, control or other-
wise affect human life or physical health.
– The device should not be used in an explosive environment.
– The device should not be used in an atmosphere with chemically active substance.

Installation
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4 Installation
CAUTION
Improper installation
Improper installation can cause serious or minor injuries and damage the device.
Installation must be performed only by fully qualified personnel.
The device is designed in a plastic enclosure for panel or wall mounting. For the dimen-
sion drawings see Appendix A.
4.1 Requirements
– Install the device in a cabinet with clean, dry and controlled environment. For further
details see 2.1.
– The device is designed for natural convection cooling that should be taken into ac-
count when choosing the installation site.
– The seal contact surface must be clean and smooth, so that the IP54 protection (for
H1 and H2) can be provided.
– The device can be placed at any angle.
– Maximum panel thickness is 15 mm
4.2 Mounting
Mounting procedure for panel mount (H1 or H2 housing):
– prepare the mounting cutout for H1 (Fig. A.1) or H2 (Fig.
A.2 and Fig. 4.1) housing
– make sure that the device is provided with the mounting
seal
– fit the device into the cutout
– insert the 2 fastening clips into the slots on the sides of
the device
– insert the screws and tighten them to fix the device
Mounting procedure for wall mount (H3):
– prepare three drilled holes according to Fig. A.3
– fix the triangle mounting bracket to the wall using three
М4x20 screws (not included) (see Fig. А.3 and Fig. 4.2a)
– hook the angle bracket on the back of the device on the
upper edge of the triangle bracket (Fig. 4.2b)
– fix the device to the triangle bracket with the screw sup-
plied (Fig. 4.2c)
Fig. 4.1 Panel mount
a)
b)
c)
Fig. 4.2 Wall mount

Wiring
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5 Wiring
DANGER
Dangerous voltage
Electric shock could kill or seriously injure.
All electrical connections must be performed by a fully qualified electrician.
Ensure that the mains voltage matches the voltage marked on the nameplate.
Ensure that the device is provided with its own power supply line and electric
fuse.
WARNING Switch on the power supply only after wiring of the device has been completed.
WARNING
Terminals 1…8 for connecting power supply and outputs are designed for a max-
imum voltage of 250 V. Don’t apply voltage above 250 V to the terminals 1...8 to
avoid an insulation breakdown or flashover. Different phases are not allowed.
5.1 General
– The layout of terminal blocks is shown in Fig. 5.1 and the terminal assignments in
Table 5.1
– Ensure that the device is provided with its own power supply line and electric fuse I =
0.5 A
– Connect the power supply to the terminals L / N
– The inputs should be wired in accordance with Fig. 5.2...5.3
– The outputs should be wired in accordance with Fig. 5.4...5.10
– The maximum conductor cross-section is 1.5 mm²
►
NOTICE
Signal cables should be routed separately or screened from the supply cables.
Only a shielded cable may be used for signal lines.
– Connect the RS485 lines to terminals D+ and D-.
– Twisted pair cable should be used for the connection to RS485 interface. Maximal
cable length is 1200 m.
Fig. 5.1 Terminal block layout
230 V AC
OUTPUT 1 OUTPUT 2
t C
RTD
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
RS485
D+ D-
TC
VOLTAGE
CURRENT
INPUT 1 INPUT 2
t C

Wiring
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Table 5.1 Terminal assignment
No
Designation
Description
1
N
Power supply
230 V AC
2
L
3
Output 1 see 5.2
4
5
6
Output 2 see 5.2
7
8
9
Input 1
+ (three-wire RTD)
10
+
11
-
12
Input 2
-
13
+
14
+ (three-wire RTD)
15
D+
RS485
16
D-
5.2 Inputs
Supported signals (see Table 2.2 and 2.3):
– Thermocouple (TC)
– Resistance thermometer (RTD)
– Linear current / voltage signal
Table 5.2 Sensor cables
Sensor type
Cable length,
max.
Resistance
(per wire), max.
Requirement
RTD 100 m 15 ohm
Equal length and
cross-section for 3-wire
TC
20 m
100 ohm
Compensation cable
Current signal
100 m
100 ohm
–
Voltage signal
100 m
5 ohm
–
– Use wires of equal length and cross section when connecting RTD
– Use a thermocouple cable when connecting TC
– Thermocouple sensing junctions of both channels must be isolated from each other
and from the grounded equipment.
– Cold junction compensation (CJC) is provided.
5.2.1 Linear signals
Connect the current or voltage signal according to Fig. 5.2, 5.3. An auxiliary voltage
source is needed.
►
NOTICE
To measure a current signal a shunt resistor R
IN
= 100 ohm (±1%) should be con-
nected in parallel.
Voltage signal can be connected directly to the input terminals.
►
NOTICE The auxiliary voltage must not exceed 36 V

Wiring
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Fig. 5.2 4-20 mA sensor wiring Fig. 5.3 0-1 V sensor wiring
5.3 Outputs
Optional outputs (see Table 2.4):
– Relay
– NPN transistor
– TRIAC
– Solid state relay
– Analog 4-20 mA
– Analog 0-10 V
5.3.1 Relay output (R)
Fig. 5.4 Relay output
5.3.2 NPN transistor (T)
The NPN transistor outputs of T type are designed to control low voltage relay up to 60 V
DC / 400 mA.
►
NOTICE
As a precaution against inadvertent current reversal on the output, a parallel diode
(Imax = 1 A, Umax=100 V) is usually included in the output circuit.
Fig. 5.5 NPN transistor outputs
5.3.3 TRIAC (C)
The resistor R1 (5…20 kohm) is used to limit the load current.
►
NOTICE
To protect thyristors and TRIACs from voltage surges an RC protect circuit should
be connected in parallel to load: R2 (47…68 ohm) and C1 (0.1 x 630 V).
10 11 12 13
10 11 12 13
3
4
5
5
4
3
+
_
K1
VD1

Wiring
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Fig. 5.6 Power TRIAC connection
Fig. 5.7 Inverse-parallel connection of two thyristors
5.3.4 Solid state relay (S)
The logic output of S type is designed to control a solid state relay with rating voltage
4…6 V DC and current up to 100 mA.
Fig. 5.8 SSR output
5.3.5 Analog 4-20 mA (I)
For the current output an external voltage source is required.
►
NOTICE
The auxiliary voltage must not exceed 36 V
The output is designed for maximal load resistance of 1 kohm.
Fig. 5.9 4-20 mA output
5.3.6 Analog 0-10 V (U)
An external power supply is required for analog output 0-10 V
►
NOTICE
The auxiliary voltage must not exceed 36 V.
The output is designed for minimal load resistance of 2 kohm.
5
4
3
5
4
3
3
4
5
100 ohm
+6 V Solid state
relay
DAC
4-20 mA
5
4
3

Wiring
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Fig. 5.10 0-10 V output
DAC
0-10 V
5
4
3
V
+
_

Operation
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6 Operation
6.1 Control elements
The device is designed in a plastic enclosure for panel or wall mounting, depending on
the model. The indicators and control elements are located on the front side of the device.
Fig. 6.1 Front view (H2 housing)
The operation of the device can be controlled with two 4-digit displays, three buttons and
five LEDs on the front panel. Indicators inform the operator about the controller and out-
put status. Displays show following information:
Table 6.1 Displays
Display
Mode
Displayed information
Upper display
(red)
Operation Process value
Configuration Parameter name
Menu “MENU”
Error Error name
Lower display
(green)
Operation Setpoint
Configuration Parameter value
Menu Parameter group
For display functions during the configuring see section 7 “Configuration”.
Table 6.2 Indicators
LED
Indication
Description
CH1
lights
upper display shows the CH1 input value
CH2
lights
upper display shows the CH2 input value
COM
flashes for 0.1 s
on data transmission
OUT1
lights
output 1 is ON
OUT2
lights
output 2 is ON
Table 6.3 Function keys
Key Description
Increase value or menu navigation
Decrease value or menu navigation
Press > 3 s
–enter the configuration mode
–exit the parameter group
Press < 1 s:
–enter the parameter group
–save the parameter and go the next one
+ + Passcode access
PROG
OUT1 OUT2
COM
CH2
CH1
TRM202

Operation
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Key Description
+ Modify the decimal part of parameter (Configuration)
+
Go back to modify the integer part of parameter
(Configuration)
6.2 Principle of operation
Fig. 6.2 Block diagram
The device has two control channels.
The input signals are continuously sampled and converted according to the selected sen-
sor type (parameters in.t1, in.t2, see Table B.1) and the measured value is displayed and
processed according to the channel settings.
Each of the measured values or the difference between them can be used as an input
value for one of the Control Units (LU). The Control Unit analyses the input value and
generates the output signal in accordance with the Control Unit settings.
Each of the outputs can be assigned to the one of the Control Units and used for control,
alarm or signal retransmission.
The device can be ordered with analog or digital outputs (see 1.4 “Ordering information”).
For three-step control the device should be equipped with two digital outputs.
6.3 First start up
►
NOTICE
Before starting
Before switching on, make sure that the device was stored at the specified ambi-
ent temperature (+1... +50°C) for at least 30 minutes.
After the device is powered on, the self-test is carried out and all LEDs are on for 2 sec-
onds. If the self-test is not successful, the error cause is displayed (see Table D.1). Oth-
erwise the automatic control is activated, the Control Unit Input value LUPv1 is shown on
the upper display and the Setpoint SP1 on the lower display. To display the LUPv2 and
SP2 values press the key .
The setpoint can be modified with the and keys, if no access protection for
the parameter is activated (see 7.11). Press key to save the setpoint and go to the
Output 1 ON/OFF control
Proportional control
Signal retransmission
ON/OFF control
Proportional control
Signal retransmission
Output 2
RS485
TRM202
LU 1
Comparator
P control
Signal
retransmission
LU 2
Comparator
P control
Signal
retransmission
Input 1
Input 2
Digital filter
Input
correction
Square
root
Digital filter
Input
correction
Square
root

Operation
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next operation parameter. Alternatively the setpoint can be modified via system menu
(see 7) in the group LvoP.
At the first start up the device will use the default parameter set. Before integrating the
device in the control system, we recommend:
– connect the device to a power source
– power up the device
– configure the parameters to suit your application (see 7)
– turn off the power
– connect the process signals and actuators to the device inputs and outputs

Configuration
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7 Configuration
In the system menu the parameters are divided into 5 groups: LvoP, Adv, LvIn, LvoU
and Comm (Fig. 7.1).
The full list of the programmable parameters is given in Table B.1.
The parameters are saved in the memory registers according to the Table C.3.
Fig. 7.1 Parameter groups
−LvoP (SP1, SP2) – operation parameters, displayed at the device start
−Adv – display settings
−LvIn – input settings
−LvoU – control and retransmission settings
−Comm – RS485 network settings
To use the functional keys in Configuration refer to Table 6.3.
Switching between control and configuration modes is carried out using the key by
default. To exit the configuration mode automatically, use the parameter rESt (Rest time).
If no keypad activity is detected during the Rest time, the configuration mode will be end-
ed. The parameter can be set in the range 5…99 s. By default rESt = OFF.
7.1 Temperature sensor
The signal from the resistance thermometer or thermocouple is converted according to
the sensor curve for the selected sensor. The type of the connected sensor should be set
in the parameter in.t1,in.t2 for both channels.
When the RTD or TC is used, the displayed accuracy for the measured temperature can
be set in the parameter dPt1, dPt2 (Decimal point displayed). The parameter is not avail-
able in the menu for sensors with the linear output. For the thermocouples with the upper
limit above 1000°C is recommended to set dPt =1, for other temperature sensors dPt =0.
When the difference ∆T as the input for a Control Unit is used and settings for dPt1 and
dPt2 are different, the ∆T value is displayed with the accuracy dPt1.
When the thermocouple is used, Cold junction compensation (CJC) enables precise tem-
perature measurement. The reference junction sensor is located near the input terminals.
The function is active by default. It should be deactivated only during the calibration. Set
the parameter wXC (Calibration parameters) to OFF to disable this function. This setting
is effective for both inputs.
7.2 Linear signal
There are additional functions for linear signal processing: decimal point position, scaling
and square root.
Operation
parameters
Display
settings
Input
settings
Control
and retransmission RS485 network
Power on
> 3 s
PROG
> 3 s
PROG
> 3 s
PROG
> 3 s
PROG
> 3 s
PROG
PROG PROG PROG PROG PROG

Configuration
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When a linear sensor is used, the accuracy can be set in the parameter dP1, dP2 (Deci-
mal point). For temperature sensors the parameter dP = 1 and is not available in the
menu.
Note: The parameter dP affects other parameters (see Table B.1).
The measurement range can be defined in the parameters:
in.L1 (in.L2) – signal lower limit
in.H1 (in.H2)– signal upper limit
If in.L < in.H, then
  =.+(. − .)∗(− )
 − 
If in.L > in.H, then
  =. − (. − .)∗(− )
 − 
where
Smax – max. input signal (for example, 20 for 4-20 mA signal)
Smin – min. input signal (for example, 4 for 4-20 mA signal)
Si – current signal value
Note:
After the Signal limits are set so that in.L1 > in.H1 (in.L2 > in.H2), the Setpoint limits
SL.L1, SL.L2, SL.H1, SL.H2 (see 7.6) and the Retransmission limits An.L1, An.L2,
An.H1, An.H2 (see 7.8.2) have to be set again.
7.2.1 Square root function
The function is provided for transmitters with output signal proportional to the square of
the measured signal. To enable the function for the input, the parameter Sqr1, Sqr2
(Lvin group) must be set to ON.
7.3 Correction
The sensor characteristic curve can be corrected by the user. Two correction parameters,
Offset and Slope, are provided for each input:
– Offset can be set in the parameter SH1, SH2 (Lvin group) in measuring units in
the range of -500…500 to correct the sensor initial error.
– Slope can be set in the parameter KU1,KU2 (Lvin group) within the range
0.5…2.0.
Set the correction parameters SH1, SH2, KU1, KU2 if necessary. When the resistance
thermometer in 2-wire connection is used, Offset should be set to compensate the sensor
line resistance.
Fig. 7.2 Offset
Fig. 7.3 Slope
T, °C
20
020 40 60 80 100
40
60
80
100
T , °C
without correction
with correction
T=T +SH
SH = 10 °C
∆T
M
M
M
T, °C
20
020 40 60 80 100
40
60
80
100
T , °C
T=T *KU
M
M
without correction
with correction

Configuration
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19
7.4 Filter
The digital filter consists of two stages.
1. The comparator is used at the first stage to detect apparent "gaps" or "outliers"
in the input signal. The Filter bandwidth for the comparator should be specified in the
parameter Fb (Fb2) (Lvin group) in measuring units within the range 0…9999. The filter
is disabled if the bandwidth is set to 0.
The difference between the last two measurements Tiand Ti-1 is determined and com-
pared with the bandwidth. If the difference exceeds the bandwidth, the last measurement
Tiwill be replaced with the (Ti-1 + Fb) and the bandwidth will be doubled to smooth the
characteristic curve. A smaller filter bandwidth slows down the response to input signal
variations (Fig. 7.4).
It is recommended to increase the filter bandwidth or disable the parameter when a low
level of interference or rapidly varying process.
If the process signal has high interferences, decrease the bandwidth to reduce the influ-
ence on the process.
Fig. 7.4 Filter bandwidth
2. The Damping with the parameters inF1, inF2 is used at the second stage. The
filter time constant can be set within the range 1…999 seconds. The higher the value, the
higher the noise resistance and the slower the output response are. When the value is
set to 0, the damping is deactivated.
Fig. 7.5 Filter time constant
without filter
with filter
t, s
T, °C
Fb
T
i-1
T
i
t
i-1
t
i
t
i