Akytec TRM138 User manual

akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] ·www.akytec.de
TRM138
8-channel on-off controller
User guide
TRM138_2016.12_0218_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 Functions...................................................................................................................................................3
1.2 RS485 network..........................................................................................................................................3
1.3 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
4.3 Wiring........................................................................................................................................................8
4.4 Inputs.........................................................................................................................................................9
4.4.1 Current / voltage signals..................................................................................................................10
4.4.2 Resistance thermometer (RTD).......................................................................................................11
4.4.3 Thermocouples (TC)........................................................................................................................11
4.5 Outputs....................................................................................................................................................11
4.5.1 Relay outputs (R).............................................................................................................................11
4.5.2 NPN transistor (T)............................................................................................................................11
4.5.3 Solid state relay (S)..........................................................................................................................12
4.5.4 Analog 4-20 mA (I)...........................................................................................................................12
4.5.5 Analog 0-10 V (U)............................................................................................................................13
5Control elements..........................................................................................................................................14
6Operation.......................................................................................................................................................16
6.1 Block diagram..........................................................................................................................................16
6.2 Input sampling.........................................................................................................................................16
6.3 Cold junction compensation....................................................................................................................16
6.4 Linear scaling..........................................................................................................................................16
6.5 Digital Filter .............................................................................................................................................17
6.6 Correction................................................................................................................................................17
6.7 Logic unit.................................................................................................................................................18
6.7.1 Comparator mode............................................................................................................................18
6.7.2 Retransmission mode......................................................................................................................20
6.8 Calibration...............................................................................................................................................21
6.9 Modbus communication..........................................................................................................................21
7Control mode................................................................................................................................................22
7.1 Alarm.......................................................................................................................................................22
7.1.1 Sensor error.....................................................................................................................................22

akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany · Tel.: [phone] · www.akytec.de
2
7.1.2 Loop Break Alarm (LBA)..................................................................................................................22
7.1.3 Alarm handling.................................................................................................................................23
7.1.4 Alarm output.....................................................................................................................................23
7.1.5 Warning indication ...........................................................................................................................23
8Configuration................................................................................................................................................24
9TRM138 Configurator...................................................................................................................................28
10 Maintenance..................................................................................................................................................29
11 Transportation and storage.........................................................................................................................30
12 Scope of delivery..........................................................................................................................................31
Appendix A Dimensions ...................................................................................................................................32
Appendix B Configuration parameters............................................................................................................33
Appendix C Modbus addressing......................................................................................................................38

Overview
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
3
3
1 Overview
This guide describes the functions, system configuration, operating instructions, pro-
gramming and troubleshooting of the 8-channel on-off controller TRM138 (hereinafter
referred to as TRM138, device, or controller).
1.1 Functions
The 8-channel on-off controller TRM138 is intended for automatic control systems in vari-
ous technological processes in different areas of industry, agriculture and utilities.
The controller provides following basic functions:
measuring of input values and transformation of the input signal according to the
sensor type
displaying the measured values and configuration parameters on 4-digit LED dis-
plays
digital filtering of the input signal (EMI-interference protection)
signal correction
creating an alarm signal in case of sensor failure, displaying the cause of the fail-
ure, using the outputs for alarm signals
creating control signals for actuating devices according to configuration parame-
ters
manual control, creating control signals using the function keys
full control over PC using RS485 interface
operating with akYtec, Modbus-RTU and Modbus-ASCII protocols in a Slave
mode
saving the set programmable parameters to non-volatile memory in case of pow-
er outage
configuration via PC or using the function keys.
1.2 RS485 network
The TRM138 uses the common standard RS485 for data exchange.
Serial interface RS485 enables communication via two-wired line in half-duplex mode.
The module supports the Modbus RTU, Modbus ASCII and akYtec protocols with auto-
matic protocol detection.
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 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 2 ends of the bus (the first and the last node).
The higher the data transmission rate, the stronger they are. A terminating resistor is
needed to minimize reflections. Line termination may be a 150 ohms value (0.5 W) resis-
tor.
The TRM138 can be used as a Slave device only. Master device can be PLC, computer
with SCADA software or control panel.

Overview
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
4
4
1.3 Ordering information
The TRM138 can be ordered in different variants depending on the required output type:
Output type (1…8):
R Relay
I 4-20 mA
S Solid state relay
T NPN transistor
U 0-10 V (outputs 5…8 only)
Various types of outputs should be indicated in the order key only in the certain sequence:
I -> S -> T -> R -> U
Example:
TRM138-H7.UUIISSTR
incorrect
TRM138-H7.IISTRRUU
Correct
TRM138-H7.RRRRRRRR
Correct

Specifications
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
5
5
2 Specifications
Table 2.1 General specifications
Power supply
230 (90…264) V AC, (47…63 Hz)
Power consumption, max.
18 VA
Analog Inputs
8
Optional outputs
8
Sampling time (per input), max.
0.6 s
Integrated voltage source
24±3 V DC, 150 mA
RS485 interface
Terminals
D+, D-
Protocols
Modbus RTU/ASCII, akYtec
Baud rate
2.4…115.2 kbit/s
Dimensions
H7
169 x 144 x 50.5 mm
Weight
approx. 450 g
Table 2.2 Standard input signals
Signal type
Measurement range (%)
Accuracy, %
0-1 V
0…100
±0.25
-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
53M
-50…+200
0.00426
Cu50
-50…+200
0.00426
100P
-200...+750
0.00391
100M
-190…+200
0.00428
Cu100
-50…+200
0.00426
TC according to IEC 60584-1:2013
J
-200…+1200
-
±0.5
(±0.25)*
N
-200…+1300
-
К
-200…+1300
-
S
0…+1750
-
R
0…+1750
-
A
0…+2500
-
TC according to GOST 8.585
L
-200…+800
-
±0.5
(±0.25)*
*with disabled cold junction compensation

Specifications
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
6
6
Table 2.4 Output types
Ordering
code
Output type
Loading capacity
R
Relay
4 A / 250 V AC
4 A / 30 V DC
T
NPN transistor
400 mA, 60 V DC
S
Solid state relay
50 mA, 4…6 V DC
I
Analog 4-20 mA
10…30 V, max. 1.3 kohm
U
Analog 0-10 V
15…30 V, min 2 kohm
2.1 Environmental conditions
The device is designed for natural convection cooling. It 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…+60°C
Relative humidity
up to 80% (at +25°C, non-condensing)
IP Code
IP54 front
Altitude
up to 2000 m above sea level

Safety
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
7
7
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 oth-
erwise 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 sub-
stance.

Installation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
8
8
4 Installation
CAUTION
Improper installation
Improper installation can cause serious or minor injuries and damage the control
panel. Installation must be performed only by fully qualified personnel.
The device is designed in a plastic enclosure for panel mounting. For the dimension
drawings see Appendix A.
4.1 Requirements
Install the device in a cabinet with clean, dry and controlled environment. For fur-
ther details see 2.1.
The module is designed for natural convection cooling. It should be taken into ac-
count when choosing the installation site.
The seal contact surface must be clean and smooth, so that the protection IP54
can be provided.
The device can be placed at any angle.
4.2 Mounting
prepare the mounting cutout according to Fig. A.1
make sure that the device is provided with the mounting seal
fit the device into the cutout
insert the 4 fastening clips into the slots on the top and the bottom of the device
insert the screws and tighten them to fix the device
4.3 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.
The layout of the terminal blocks is shown in Fig. 4.1 and the terminal assign-
ments in Table 4.1.
Ensure that the device is provided with its own power supply line and electric fuse
I = 1 A.
Connect the power supply to the terminals L / N.
The inputs should be wired in accordance with Fig. 4.2...4.8.
The outputs should be wired in accordance with Fig. 4.9...4.17.
The maximum conductor cross-section is 1.5 mm².
Disabled inputs (parameter „Sensor type“ = OFF) should be short-circuited ac-
cording to Fig. 4.7.
►
NOTICE
Signal cables should be routed separately or screened from the supply cables.
Only a shielded cable may be used for signal lines.

Installation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
9
9
►
NOTICE
The integrated voltage source 24 V DC can be used for inputs or outputs, but not
for both groups.
Connect the RS485 lines to terminals D+ and D-.
For the connection to RS485 interface twisted pair cable should be used. Maxi-
mal cable length is 1200 m.
Fig. 4.1 Layout of terminal blocks
Table 4.1 Terminal assignment
Terminal
Signal
Terminal
Signal
Terminal
Signal
1
Output 1-3 (–)
19
Output 8-2 (+)
37
Input 4-3
2
Output 1-2 (+)
20
Output 8-1
38
Input 3-3
3
Output 2-3 (–)
21
not connected
39
Input 4-2
4
Output 2-2 (+)
22
not connected
40
Input 3-2
5
Output 3-3 (–)
23
Power supply (N)
41
Input 4-1
6
Output 3-2 (+)
24
Power supply (L)
42
Input 3-1
7
Output 4-3 (–)
25
Input 8-3
43
Input 2-3
8
Output 4-2 (+)
26
Input 7-3
44
Input 1-3
9
Output 5-3 (–)
27
Input 8-2
45
Input 2-2
10
Output 5-2 (+)
28
Input 7-2
46
Input 1-2
11
Output 5-1
29
Input 8-1
47
Input 2-1
12
Output 6-3 (–)
30
Input 7-1
48
Input 1-1
13
Output 6-2 (+)
31
Input 6-3
49
RS485 D+
14
Output 6-1
32
Input 5-3
50
RS485 D-
15
Output 7-3 (–)
33
Input 6-2
51
–24 V voltage source
16
Output 7-2 (+)
34
Input 5-2
52
+24 V voltage source
17
Output 7-1
35
Input 6-1
18
Output 8-3 (–)
36
Input 5-1
4.4 Inputs
Supported signals (see Table 2.2 and 2.3):
Standard signal 4-20 mA / 0-1 V
Thermocouple (TC)
Resistance thermometer (RTD)

Installation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
10
10
Table 4.2 Sensor cables
Sensor type
Cable length,
max
Resistance (per
wire), max
Cable type
RTD
100 m
15 ohm
Equal length and cross-
section, (2- or 3-wire)
TC
20 m
Compensation cable
Standard signal
(current or voltage)
100 m
100 ohm
2-wire
Fig. 4.2 Input connections
4.4.1 Current / voltage signals
Fig. 4.3 4-20 mA sensor wiring
Fig. 4.4 4-20 mA sensor group wiring (example)
►
NOTICE
To measure a current signal a shunt resistor RL= 100 ohm (±1%) should be con-
nected in parallel.
Fig. 4.5 0-1 V sensor wiring
Fig. 4.6 Short-circuiting of a disabled
input

Installation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
11
11
4.4.2 Resistance thermometer (RTD)
Two- or three-wire sensors can be connected.
Fig. 4.7 RTD sensor wiring
4.4.3 Thermocouples (TC)
Optional cold junction compensation (CJC) is provided.
Fig. 4.8 TC sensor wiring
4.5 Outputs
Optional outputs (see Table 2.4):
–Relay
–NPN transistor
–Solid state relay
–Analog 4-20 mA
–Analog 0-10 V
4.5.1 Relay outputs (R)
Fig. 4.9 Relay output Q1…Q4
Fig. 4.10Relay output Q5…Q8
4.5.2 NPN transistor (T)
The NPN transistor outputs are designed to control low voltage relays up to 60 V DC/ 400
mA.
►
NOTICE
As a precaution against inadvertent current reversal on output, a parallel diode is
usually included in the output circuit.

Installation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
12
12
Fig. 4.11NPN transistor outputs Q1…Q4
Fig. 4.12NPN transistor outputs Q5…Q8
4.5.3 Solid state relay (S)
Logic outputs are designed to control solid state relays with rating voltage 4…6 V DC and
current up to 50 mA.
Fig. 4.13SSR outputs Q1…Q4
Fig. 4.14SSR outputs Q5…Q8
4.5.4 Analog 4-20 mA (I)
An external voltage source for analog outputs is required. The voltage is calculated as
follows:
Umin < U < Umax
Umin = 10 V + 0.02 A x R
Umax = Umin + 2.5 V
where
Umin, Umax –minimum and maximum permissible voltage, V
R –current-limiting resistor, ohm
If U > Umax it is necessary to use the additional resistance R for current limitation. It is
calculated as follows: Rmin< R < Rmax
Rmin = (U –Umax) / Imax
Rmax = (U –Umin) / Imax
where
Imax –maximum output current (20 mA).
►
NOTICE
If an external voltage source is used, the voltage must not exceed 30 V.
Fig. 4.154-20 mA outputs Q1…Q4
Fig. 4.164-20 mA outputs Q5…Q8

Installation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
13
13
4.5.5 Analog 0-10 V (U)
An external voltage source for analog outputs is required.
►
NOTICE
If an external voltage source is used, the voltage must not exceed 30 V.
The output is designed for minimal load resistance of 2 kohm.
The load resistance R should be in the range of 2…10 kohm.
Fig. 4.170-10 V outputs Q5…Q8

Control elements
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
14
14
5 Control elements
Indicators and control elements are located on the front side of the device.
Fig. 5.1 Front view
The operation of the device can be controlled with 4 LED displays, 10 LED indicators and
6 function keys on the front panel.
Table 5.1 Displays
Display
Mode
Displayed information
Z1
Control
Measured or calculated value of the current control channel
in two display modes:
–Manual –displayed channel can be selected via the
function keys, the corresponding LED from the group
CHANNELS lights
–Cyclic –channels are displayed in a loop (the period
ind.t can be set from 1 to 600 s)
In Logic Unit Measuring mode the display is blank
Error
Number of channel with faulty sensor
Z2
Control
Setpoint for current control channel
Error
Error code
Z3
Logic Unit input for current channel (parameter C.in)
Blinking point after the number, if TC selected and CJC not
activated
Z4
Number of the output connected to the channel (P1…P8)
In Logic Unit Measuring mode - two dashes (- -) as a place
holder
For display functions during configuration see section 8 Configuration.

Control elements
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
15
15
Table 5.2 LEDs
LED
Indication
Description
CHANNEL 1…8
lights
Current control channel
blinking
Alarm or error
OUT1
lights
Output of the current channel is ON (for digital
outputs only)
STOP
lights
Manual display mode
Table 5.3 Function keys
Key
Description
Select the current channel for display or
Manual Output Control
Switch to Configuration mode
Disable alarm output or
shift the data on the Z1 display if too long
Switch the current channel to Manual Output Control mode or
switch from Configuration to Control mode
Switch the current channel between Manual and Cyclic display
modes

Operation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
16
16
6 Operation
The controller has two operating modes: Control and Configuration (see sections 7 and 8).
6.1 Block diagram
Fig. 6.1 Block diagram
An analog input signal from the resistance thermometer or thermocouple is converted
according to sensor curve into a standard signal. The measured value is digitalised, ana-
lysed and processed in accordance with the set parameters. The results are saved in
memory registers according to the Table C.2. For the complete parameter list refer to the
Table B.1.
6.2 Input sampling
Inputs are sampled cyclically. An input is included into the sampling list when a signal
type is selected in the parameter in-t (PL-1 group). The input is excluded from the list if
the parameter in-t is set to OFF.
The order and the rate of sampling for each input are defined by priority which can be set
as a number from 1 to 8 in the parameter Prt (PL-1 group). The highest priority is 8.
6.3 Cold junction compensation
The cold junction compensation provides a precise temperature measurement with ther-
mocouples. A reference junction sensor is located near the input terminals. To enable the
function set the parameter CJ-.C (PL-0 group) to ON. This setting is effective for all in-
puts.
Other filters and corrections for individual inputs are described in sections 6.4 and 6.5.
6.4 Linear scaling
To scale the linear signal (current or voltage) the measurement limits must be set. Pa-
rameters Ain.L “Signal lower limit” and Ain.H “Signal upper limit” should be set in physi-
cal units.
If Ain.L<Ain.H, then
     󰇛    󰇜 󰇛 󰇜
  
If Ain.L>Ain.H, then

Operation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
17
17
     󰇛    󰇜 󰇛 󰇜
  
where Smax –signal upper limit (for example, 20 for 4-20 mA)
Smin –signal lower limit (for example, 4 for 4-20 mA)
Si –current signal value
6.5 Digital Filter
The digital filter consists of two stages.
–Comparator is used at the first stage to detect the input signals with apparent
"gaps" or "outliers". For this purpose the filter bandwidth for the comparator
should be specified in the parameter in.FG in physical units. The difference be-
tween the last two measurements is compared with the bandwidth. If the differ-
ence is greater than the bandwidth, the measurement is considered to be unreli-
able and must be repeated. If an unreliable result was caused by a fault, the sec-
ond measurement confirms this and the first measurement value is ignored as an
error. If the bandwidth is set to ‘0’, the comparator is switched off.
–Damping is used at the second stage. The filter time constant should be set in
parameter in.Fd in seconds. The higher is the value, the higher is the noise re-
sistance and the slower is the input response. When the value is set to ‘0’, damp-
ing is switched off.
Fig. 6.2 Actual temperature TR
Fig. 6.3 Measured temperature TM
(filter is OFF)
Fig. 6.4 Comparator is ON
Fig. 6.5 Comparator and damping are ON
6.6 Correction
The sensor characteristic curve can be corrected by the user. Two correction parameters
are provided for each input: the offset and the slope.
–Offset can be set in the parameter in.SH in physical units to correct the sensor in-
itial error, for example, when you use a RTD.
–Slope can be set in the parameter in.SL within the range from 0.9 to 1.1.

Operation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
18
18
Fig. 6.6 Offset
Fig. 6.7 Slope
6.7 Logic unit
The combination of a logic unit with its input parameter and connected output defines the
control channel (see Fig. 6.1). Connections can be established using the function keys or
the configuration tool.
The input of the logic unit can be set in the parameter C.in (PL-2 group).
If a value from d1 to d8 is selected, one of the device inputs is directly connected to the
LU. Also an average value from 2 to 8 inputs (F1…F7), difference between 2 different
inputs (A1…A4) or rate of change (units/min.) for each input (r1…r8) can be selected. If
the logic unit should not be used, set the parameter C.in to OFF.
An additional differential filter for the LU input values r1…r8 “Rate of change” is applied.
The performance of this filter can be set in the parameter in.rd “Differential filter time
constant” (PL-1 group) for each input.
Each logic unit can be connected to one of 8 outputs, specified in the parameter C.dr
(PL-2 group) for this LU. (for example see Table B.1, PL-3 group “Standard configura-
tions”). Don’t forget that one output can be connected with several LUs and each of them
can switch the output on (OR logic).
Each LU can work in different modes defined in the parameter AL.t (PL-2 group):
–Measuring (AL.t = 0)
–Comparator
oHeating (AL.t = 1)
oCooling (AL.t = 2)
oAlarm within limits (AL.t = 3)
oAlarm outside limits (AL.t = 4)
–Retransmission (AL.t = 5).
The LU connected to the output of I or U type can work only in Measuring or Retransmis-
sion modes. In the Measuring mode the LU transmits the input signal only to the display,
in the Retransmission mode –to the connected output. Control signal is not generated.
If the logic unit works in one of the comparator modes it must be connected to a digital
output (R, S or T type).
6.7.1 Comparator mode
In the Comparator mode the LU compares the input signal with the setpoint considering
the hysteresis value Δand generates the output control signal. Setpoint and hysteresis
values are specified in the parameters C.SP and HУSt (PL-2 group).

Operation
akYtec GmbH · Vahrenwalder Str. 269 A · 30179 Hannover · Germany Tel.: [phone] · www.akytec.de
19
19
Output time diagrams for different comparator modes are shown in Fig. 6.8.
Fig. 6.8 Time diagrams for Comparator modes
Additional settings for Comparator modes:
1. If a logic unit is used in “Alarm Outside Limits” mode, it can be useful to block the
first alarm, because the controlled value must not be inside the valid range when
starting control. To use the option set the parameter bL.St (PL-2 group) to ON.
Output time diagrams for this option are shown in Fig. 6.9.
Fig. 6.9 Option “Ignore alarm on start”
2. The parameters Ht.on and Ht.oF (PL-2 group) are switch-on and switch-off de-
lays. They can be used to protect the output element from frequent switching
Output time diagram for this option is shown in Fig. 6.10.
3. Also the minimum duration of on- or off state of output irrespective of the input
state can be set in the parameters dL.on and dL.oF (PL-2 group) accordingly.
Output time diagram for this option is shown in Fig. 6.11.