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Hardware and Engineering

LE 4-206-AA2
Analog LE for Current Signals

09/99 AWB 2700-1331 GB

1st published 1998, edition 07/98
2nd published 1999, edition 09/99

© Moeller GmbH, Bonn

Author:

Peter Roersch

Editor:

Karola Großpietsch

Translator:

Terence Osborn

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Caution!

Dangerous electrical voltage!

Before commencing the installation

Disconnect the power supply of the 
device.

Ensure that the device cannot be 
accidentally restarted.

Verify isolation from the supply.

Earth and short circuit.

Cover or enclose neighbouring units that 
are live.

Follow the engineering instructions 
(AWA) of the device concerned.

Only suitably qualified personnel may 
work on this device/system.

Before installation and before touching 
the device ensure that you are free of 
electrostatic charge.

Connecting cables and signal lines 
should be installed so that inductive or 
capacitive interference do not impair the 
automation functions.

Install automation devices and related 
operating elements in such a way that 
they are well protected against 
unintentional operation.

Suitable safety hardware and software 
measures should be implemented for 
the I/O interface so that a line or wire 
breakage on the signal side does not 
result in undefined states in the 
automation devices.

Ensure a reliable electrical isolation of 
the low voltage for the 24 volt supply. 
Only use power supply units complying 
with IEC 60 364-4-41 or HD 384.4.41 S2.

Deviations of the mains voltage from the 
rated value must not exceed the 
tolerance limits given in the 
specifications, otherwise this may cause 
malfunction and dangerous operation.

Emergency stop devices complying with 
IEC/EN 60 204-1 must be effective in all 
operating modes of the automation 
devices. Unlatching the emergency-stop 
devices must not cause uncontrolled 
operation or restart.

Devices that are designed for mounting 
in housings or control cabinets must only 
be operated and controlled after they 
have been installed with the housing 
closed. Desktop or portable units must 
only be operated and controlled in 
enclosed housings.

Measures should be taken to ensure the 
proper restart of programs interrupted 
after a voltage dip or failure. This should 
not cause dangerous operating states 
even for a short time. If necessary, 
emergency-stop devices should be 
implemented.

IBM is a registered trademark of International 
Business Machines Corporation.

All other brand and product names are 
trademarks or registered trademarks of the 
owner concerned.

All rights reserved, including those of the 
translation.

No part of this manual may be reproduced in 
any form (printed, photocopy, microfilm or 
any otherprocess) or processed, duplicated 
or distributed by means of electronic 
systems without written permission of 
Moeller GmbH, Bonn.

Subject to alterations without notice.

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Contents

About This Manual 

3

1

About The LE 4-206-AA2

5

Application range 

5

Setup 6
Software requirements 

6

2

Mounting

7

Mounting on top-hat rail 

7

Mounting on mounting plate via fixing feet 

8

Installing in the control cabinet 

9

Fitting/removing the terminal strip 

9

3

Engineering

11

Electromagnetic compatibility (EMC) 

11

Connection overview 

12

Connecting to the PS 4-200/300,
EM 4-204-DX1 13
Connecting analog cables 

14

Grounding the analog cables 

15

4

Configuration and Parameter Setting

19

Setting the input and output parameters 

19

Setting parameters for the PROFIBUS-DP
network 22

5

Addressing/Operation/Diagnostics

23

Addressing 23
Operation 24
Diagnostics 25
Diagnostics for the PROFIBUS-DP network 

30

6

Analog Value Representation

31

Analog/digital conversion 

31

Appendix 

41

Technical Data 

41

Index 

43

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About This Manual

This manual is written for engineers and technicians 
with PLC experience.

It provides the special information required for 
connecting the module correctly, as well as for 
configuring and programming it with the 
Sucosoft S 40 programming software.

To use this manual, a knowledge of the following is 
required:

the master in use

the programming software

You will find the required information in:

the “Hardware and Engineering” manual of your 
master

the manual “Sucosoft S 40, User Interface” 
(AWB 2700-1305 GB)

the manual “Sucosoft S 40, Language Elements 
for PS 4-... and PS 416” (AWB 2700-1306 GB)

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About This Manual

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The symbols used in this manual have the following 
meaning: 

왘 Indicates handling instructions.

 

Attracts your attention to interesting tips and 
additional information.

Note
Warns you of damage to property. Product, parts 
in its surrounding or data may be severely 
damaged

Caution!
Warns you of severe damage to property. 
Product, parts in its surrounding or data may be 
severely damaged

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1

About The LE 4-206-AA2

Application range

The LE 4-206-AA2 converts analog current signals of 
0(4) to 20 mA into digital values, and digital values 
into analog current signals of 0(4) to 20 mA. 

In HVAC applications and in process engineering, it 
can be used to process the analog signals of sensors 
that record physical values such as pressure, 
temperature, and flow rate. The analog output 
currents can be used to regulate these variables.

The LE 4-206-AA2 can be used to expand the analog 
I/O of the PS 4-200, PS 4-300 compact PLCs as well 
as the EM 4-204-DX1 remote expansion module.

Two modules can be used for each PLC. They are 
fitted directly to the side of the PLC in the first or 
second position.

Special features

Type of inputs/outputs

0(4) to 20 mA

Number of I/O

4 inputs/2 outputs

Resolution

12 Bit

Error detection

Out-of-range values,
wire breakage, reverse polarity

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About The LE 4-206-AA2

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Setup

Figure 1:  Setup of the LE 4-206-AA2

햲 Device designation with HAEG 18 3 6.5
햳 Plug-in screw terminal for the inputs/outputs

Software requirements

Sucosoft S 40 from version 3.0 is required for 
configuring the LE 4-206-AA2 with the 
PS 4-200/300.

0V

A

I

0

I

1

0V

A

LE4-206-AA2

Analog
Output

Analog
Input

0V

A

I

0

I

1

0V

A

0V

A

I

2

I

3

0V

A

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2

Mounting

Mounting on top-hat 
rail

The LE 4-206-AA2 can be fixed on a top-hat rail or on 
a mounting plate via fixing feet. The relevant 
dimensions are given in the Appendix.

왘 Hook the back of the device against the top edge 

of the top-hat rail.

왘 Use a screwdriver to slide the spring-loaded clip 

 out of the device 

.

왘 Push the device against the top-hat rail 

.

왘 Remove the screwdriver. The spring-loaded clip 

should snap back into position and hold the 
device securely.

왘 Check that the device is attached properly.

Figure 2:  Mounting on top-hat rail

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Mounting

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Mounting on mounting 
plate via fixing feet

왘 Turn over the module. Here you will see the slots 

provided for the fixing feet 

 on the back of the 

module.

왘 Push the fixing feet into the slots until the lugs 

 

snap into position.

왘 Ensure that all fixing feet are snapped securely 

into position.

왘 Fasten each fixing foot to the mounting plate 

 

using an M4 screw.

Figure 3:  Mounting on mounting plate

LE 4 -...

EM 4 -... / PS 4-...

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Installing in the control 
cabinet

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Installing in the control 
cabinet

Ensure the following points when installing in a 
control cabinet:

왘 Fasten the modules horizontally in the control 

cabinet.

Proceed as follows to prevent electromagnetic 
interference from impairing the function of the 
electronic control section:

왘 Ensure a spacing between the cable duct 

 and 

the module of at least 5 cm (2").

왘 Keep the control 

 and power sections 

 apart.

Figure 4:  Arrangement in the control cabinet

Fitting/removing the 
terminal strip

50

Caution!
Electrostatic charge can destroy the equipment.
Make sure you are free of electrostatic charge 
before working on the input/output terminals.

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Mounting

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If you wish to pre-wire a circuit or change a module, 
you can remove the plug-in screw terminal from the 
module.

왘 Open out fully the cover of the plug-in screw 

terminal.

왘 Remove the plug-in screw terminal at its cover.
왘 Use the same procedure for the other plug-in 

screw terminal.

Figure 5:  Fitting/removing the plug-in screw terminal

Proceed as follows to fit the plug-in screw terminal 
into the module:

왘 Open out fully the cover of the plug-in screw 

terminal.

왘 Fit the plug-in screw terminal into the slot and 

press it into position.

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3

Engineering

Electromagnetic 
compatibility (EMC)

The following engineering measures must be 
observed in order to meet the requirements of the 
EMC regulations and comply with the following 
European EMC standards:

EN 50 081-2 (Emission)
EN 50 082-2 (Immunity)

Other engineering instructions are given in the 
manual “EMC Guidelines for Automation 
Systems”, AWB 27-1287-GB and the EMC 
manual Electromagnetic Compatibility of 
Machines TB 02-022 GB.

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Engineering

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Connection overview

Figure 6:  Connection overview

햲 Socket connector
햳 Plug-in screw terminal
햴 Connection cross-sections:

flexible with ferrule 0.22 to 1.5 mm

(AWG 23 to AWG 16) 
solid 0.22 to 2.5 mm

2

 

(AWG 23 to AWG  13)

햵 Designation strips
햶 Connector strip

0V

A

I

0

I

1

0V

A

0V

A

I

0

I

1

0V

A

0V

A

I

2

I

3

0V

A

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Connecting to the 
PS 4-200/300, 
EM 4-204-DX1

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Connecting to the 
PS 4-200/300,
EM 4-204-DX1

왘 Connect the LE 4-206-AA2 to the PS 4-200/300, 

EM 4-204-DX1 via the plug connector.

Figure 7:  Connecting to the PS 4-200/300, EM 4-204-DX1

The LE 4-206-AA2 must be mounted on the top-
hat rail or fastened to the mounting plate before 
connecting it to the  4-200/300, EM 4-204-DX1.

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Engineering

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Connecting analog 
cables

The following example shows the connection of the 
analog cables to the LE 4-206-AA2:

Figure 8:  Connecting the analog cables

햲 Screening of the analog cables (see Figure 9)
햳 Connection for sensors
햴 Connection for actuators

Analog

Output

M

A

0V

0

I

1

I

A

0V

A

0V

2

I

3

I

A

0V

A

0V

0

I

1

I

A

0V

Analog

Input

LE 4-206-AA2

 

0(4) –
20 mA

 

 

0(4) –
20 mA

0(4) –
20 mA

0(4) –
20 mA

M

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Grounding the analog 
cables

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Grounding the analog 
cables

Only use screened cables for analog lines (see 
Figure 9). 

왘 Strip the cable sheathing near the contact clip 햵
왘 Fit a contact clip on the bared part of the analog 

cables.

왘 Make a low impedance connection between the 

contact clip and the ground potential, such as the 
terminal clip 

햴, on the top-hat rail.

왘 Ensure that all connections are corrosion proof 

and that the paint is removed from the connection 
point of mounting plates.

왘 Pull back the screen at the ends of the analog 

input cables.

왘 Isolate the screen with suitable material such as 

heat shrinkable tubing 

햳.

왘 Ground the top-hat rail with a large contact area.

Note!
Electromagnetic interference
Interference and line-conducted interference 
according to ENV 50 140 and ENV 50 141 can 
corrupt your measuring result by up to 20 %.
A faulty connection of the module may produce 
interference for other components.

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Engineering

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Legend for Figure 9
햲 Top-hat rail
햳 Heat shrinkable tubing
햴 Terminal clip
햵 Contact clip
햶 Screw

Items 

햴, 햵 and 햶 are part of the ZB 4-102-KS1 

screen grounding kit. This grounding kit must be 
ordered separately.

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Grounding the analog 
cables

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Figure 9:  Grounding the screen for analog cables

Analog
Input

0

I

1

0 V

A

I

0 V

A

2

I

3

0 V

A

I

0 V

A

0

I

1

0 V

A

I

0 V

A

Analog
Output

LE 4-206-AA2

PS 4-201-MM1

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4

Configuration and Parameter Setting

The LE 4-206-AA2 is configured in the topology 
configurator of the Sucosoft S 40 programming 
software:

왘 Open the Topology configurator and choose 

‹Edit  ➞ Local Expansion›.

왘 Select the LE 4-206-AA2 from the device list. 

When selected the LE 4 will be highlighted.

왘 Choose ‹Edit  ➞ Parameters› and set the input 

and output parameters of the device.

Setting the input and 
output parameters

The input and output parameters can be set to meet 
the requirements of the application at hand. The 
following parameters can be set:

Averaging (only for input channels)

Value range of the input/output current for each 
channel

Scaling of inputs and outputs for each channel

The fastest refresh time for all I/O is achieved if 
Averaging and Scaling are not selected. Without 
these, the refresh time is approx. 3 ms including the 
basic filter process. If Scaling is activated without 
Averaging, the time required is 4 ms.

Factory setting: 

No averaging

Value range 0 to 20 mA

No scaling

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Configuration and 
Parameter Setting

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Averaging

This setting applies to all the inputs.
The averaging result depends on the scan interval 
and the number of mean values used. The scan 
interval is the time in which all analog input values are 
to be scanned and supplied to the PLC.
The averaging result depends on the selected 
number of values and the scan interval. These two 
parameters determine the time required for 
averaging:

Example:

The different combinations and the time required for 
averaging are set in the Sucosoft S 40 Parameter 
Editor.

The table shows some combinations of scan interval 
and number of values to form the average.

If the input changes from 0 to 20 mA, the final digital 
value will be reached in 6 times the time required for 
forming the averaging value.

Scan interval 

3

3

3

3 Number of averaged values = Averaging time

4 ms 

3 8 = 32 ms

Number of averaged 
values

Scan/refresh 
interval [ms]

Averaging [ms]

2

4

8

4

4

16

8

4

32

16

4

64

16

16

256

16

62.5

1000

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Setting the input and 
output parameters

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The outputs are also refreshed within the scan 
interval for the inputs. In other words, the input scan 
interval is at the same time the refresh interval for the 
outputs.

Selecting a low scan interval and a small number of 
values ensures a fast response in digital output value 
to changes in the analog input signal. This will cause 
a slight oscillation of value. To avoid oscillations 
choose a larger scan interval with a large number of 
values.

Value range of the input/output current

The value range for each input and output can be set 
separately. Ranges of 0 to 20 mA (0 to 4095) and 4 to 
20 mA (820 to 4095) can be selected.

Scaling the inputs and outputs

Scaling can be selected irrespective of whether 
Averaging has been selected or not. This option 
allows you to assign each input and output signal 
from 0(4) to 20 mA a specified range of values for the 
application concerned. The range is defined by 
means of a minimum and maximum limit value. 

If Scaling has been selected, enter the minimum and 
maximum value required in the measuring range 
window. The following limit values are possible

absolute max. limit value: +32767
absolute min. limit value: –32768

Further information is provided in the chapter Analog 
Value Display

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Configuration and 
Parameter Setting

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Setting parameters for 
the PROFIBUS-DP
network

To use LE 4-206-AA2 as a local expansion module 
for the EM 4-204-DX1, the Averaging and Value 
Range parameters must be set in the CFG 
Configurator.

Scaling

If the LE 4-206-AA2 is connected to PROFIBUS-DP 
via the EM 4-204-DX1, scaling applies to all channels.

If Scaling has been selected, enter the minimum and 
maximum value required in the measuring range 
window. The following limit values are possible

absolute min. limit value –32768 
absolute max. limit value: +32767

Since the PROFIBUS-DP standard only permits 
positive values between 0 and 65535, the negative 
limit value must be converted with the following 
formula (twos' complement of the positive value:

Example of a negative limit value:
Enter the range from –120 to +130. Set the following 
parameters:

min. limit value: 65536 – 120 = 65416
max. limit value: 130

Example of a positive limit value:
Enter the range from 0 to +100. Set the following 
parameters:

min. limit value: 0
max. limit value: 100

Ensure the following: min. limit value < max. limit 
value.
An incorrect entry will cause the output of 0 or 
4 mA

655366 – negative number = Parameter number

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5

Addressing/Operation/Diagnostics

Addressing 

Addressing the inputs and outputs of the LE 4-206-
AA2 is described in the “Hardware and Engineering” 
manual of the master in use. The data type of the 
analog values is always of “Integer”. The operands 
are addressed as follows:

VAR
AnaInp AT%IAW0.0.x.y:INT; (*Input scan*)
AnaOutp AT%QAW0.0.x.y:INT; (*Address output*)
END_VAR

LD AnaInp
ST AnaOutp

x = 1, 2:

Module number

y = 0, 2, 4, 6: I/O number

 

Input designation

Input number

Operand

I

0

0

IAW0.0.x.0

I

1

2

IAW0.0.x.2

I

2

4

IAW0.0.x.4

I

3

6

IAW0.0.x.6

Output designation

Output number

Operand

I

0

0

QAW0.0.x.0

I

1

2

QAW0.0.x.2

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Addressing/Operation/
Diagnostics

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Operation

Startup behaviour

Once the power supply has been switched on, the 
PLC sends the parameters set by the user to the 
LE 4-206-AA2 and starts the exchange of process 
data. No process data is exchanged if the PLC is in 
HALT after being switched on. All the outputs of the 
LE 4-206-AA2 will remain at 0 mA.

HALT/RUN changeover

Startup behaviour depends on the following.

LE parameters set beforehand
The parameters are transferred with the program. In 
this case, the LE requires about 500 ms to adapt the 
parameters. The I/O values can then be transferred. 
During the calculation period, diagnostics bit 2 is set 
in diagnostics byte 1. The Local Status (DLS) 
diagnostics bit in the diagnostics status word of the 
PS 4 is not set.

In order to ensure that the user program only sends 
and receives plausible values, structure the program 
so that the scanning and transfer of values is 
controlled by the diagnostics bit.

Existing parameters in the LE:
When the PLC switches from Halt to Run, 
communication with the LE 4-206-AA2 is resumed 
immediately.

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Diagnostics

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RUN/HALT changeover

When the PLC changes from RUN to Halt the PLC 
continues to scan the input signals and saves them 
in its internal memory. This means the plausible 
values are available as soon as the PLC is restarted. 
Otherwise, with a long scan time selected, the 
averaging process would require several minutes to 
provide values within range of the recorded signal.

If the PLC is in Halt, the output currents are restricted 
to the selected value range accordingly.

Diagnostics 

The diagnostics data of the LE 4-206-AA2 is stored 
in two diagnostics bytes. The first bytes contains all 
signals relating to correct functioning and a general 
signal for out-of-range values or wire breakage on an 
input.

The second diagnostics byte determines on which 
input the wire breakage or out-of-range value has 
occurred.

Value range

Output current

0 to 20 mA

0 mA

4 to 20 mA

4 mA

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Addressing/Operation/
Diagnostics

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Diagnostics byte 1

Out-of range values
An out-of-range value is indicated if the current value 
is 5 % higher than the maximum input current of 
20 mA or is in the negative range

^ –1 mA.

Wire breakage
A wire breakage can only be detected if the value 
range for the input is 4 to 20 mA. An error signal will 
be output if the current falls below 3 mA.

Further information is provided in the chapter 
“Analog Value Processing”

Structure of the first diagnostics byte:

Bit

7

6

5

4

3

2

1

0

Bit 0 = 0:

1:

ok
no/incorrect module

Bit 1 = 0:

1:

ok
wire breakage/out-of-range value

Bit 2 = 0:

1:

ok
Impermissible value

Bit 3 = 0:

1:

ok
Time monitoring

Bit 4 to 7: not assigned

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Diagnostics

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No/incorrect module (Bit 0)
(No/unexpected module)
No or incorrect local expansion module.
Check

whether the type of local expansion module is 
correct,

whether the LE bus connection is properly fitted.

Replace the faulty local expansion modules.

The signal is cleared automatically once the fault is 
rectified. A reset in the diagnostics status of the CPU 
is not necessary.

Wire breakage/out-of-range value (Bit 1)

The module measuring channel has detected a wire 
breakage in the sensor or the measured value at the 
channel specified is out of range.
If necessary, more detailed troubleshooting for the 
sensor concerned is possible using the measured 
values available. Call the Display/Force I/O window 
for this station.

The signal is cleared automatically once the fault is 
rectified.

Values not valid (Bit 2)

The local expansion module will make an internal 
parameter setting after power is restored; analog 
values that have been read or written are invalid for 
this time. Permissible values can be read or output as 
soon as the signal is cleared automatically.

A reset in the diagnostics status of the CPU is not 
necessary.

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Addressing/Operation/
Diagnostics

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Time monitoring (Bit 3)
(Timeout)
The LE 4-206-AA2 is not reporting its presence. This 
may be due to a hardware error. Try to restart the 
system by switching it off and then on again. Replace 
a faulty module.

The signal is cleared automatically once the fault is 
rectified. A reset in the diagnostics status of the CPU 
is not necessary.

Scanning
Diagnostics byte 1 is scanned in bit or byte format 
with the following syntax:

The variable declaration has not been shown 
here. Refer to the manual Language Elements for 
PS 4/PS 416 (AWB 2700-1306 GB) for a general 
declaration.

Bit format

Byte format

LD %ISB0.0.x.0.y

LD %ISB0.0.x.0

x = 1 or 2 (module number)
y = 0 to 7 (bit number)

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Diagnostics

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Diagnostics byte 2

Structure of the second diagnostics byte:

Bit 0 to 3:

Wire breakage inputI

x

Bit 4 to 7:

Out-of-range value input I

x

Wire breakage input I

(Wire breakage input x)

Wire breakage on the measuring channel indicated.

The signal is cleared automatically once the fault is 
rectified.

Out-of-range value input I

x

The measured value on the measuring channel 
indicated out-of-range.

The signal is cleared automatically once the fault is 
rectified.

Scanning
Diagnostics byte 2 is scanned in bit or byte format 
with the following syntax:

Bit

7

6

5

4

3

2

1

0

Bit format

Byte format

LD %ISB0.0.x.1.y

LD %ISB0.0.x.1

x = 1 or 2 (module number)
y = 0 to 7 (bit number)

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Addressing/Operation/
Diagnostics

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Diagnostics for the 
PROFIBUS-DP network

The LE 4-206-AA2 can be used as a local expansion 
for the EM 4-204-DX1 in a PROFIBUS-DP line.

A detailed description of the diagnostics on the 
PROFIBUS-DP line is provided in the the Hardware 
and Engineering manual of the EM 4-204-DX1 
(AWB 27-1315 GB) and in the manuals of the 
masters used.

The scanning and evaluation of the diagnostics bytes 
for the PS 416-NET-440 master card are described 
in the Hardware and Engineering manual 
(AWB 2700-1330 GB).

Scanning the diagnostics bytes with operations such 
as LD%ISB1.2.1.0, as used for Sucosoft-K-stations, 
is not possible with PROFIBUS-DP. An error 
message will be output if this instruction is present.

The diagnostics byte of the LE 4-206-AA2 
contains a central signal for wire breakage and 
out-of-range errors.

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6

Analog Value Representation

Analog/digital 
conversion

The LE 4-206-AA2 converts analog input signals to 
12-bit digital values and vice versa. The basic digital 
range of values is represented from 0 to 4095 dec or 
0 to FFF hex (12 bit).

Figure 10:  Analog/digital conversion

Calculation example

In order to calculate the digital or analog value the 
step width must first be defined.

19.99

4

0

mA

820

4095

0

0

334

0FFF

dec.

hex

background image

Analog Value 
Representation

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Calculating the step width:

The digital value will change by one bit if there is a 
change in the analog input value of 0.00488 mA 
(increment).

Calculating the analog value
The analog value equivalent of a digital value x = 
2048 is calculated as follows:

Example:

Calculating the digital value
The digital value equivalent of an analog value y = 5 
mA is calculated as follows:

Example:

(the value shown is 1024)

Upper

lower meas. limit

2

12

---------------------------------------------------------------------

20 mA

4096

-----------------

0.00488 mA

=

=

x

3 Step widte Analog value

=

2048 

3 0.00488 9.99 mA

=

y

Step width

----------------------------

Digital value

=

5

0.00488

---------------------

1024.6

=

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Analog/digital conversion

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Value range of inputs

Inputs for 0 to 20 mA

Figure 11:  Value range for current inputs 0 to 20 mA

If the input current goes over 20 mA, the maximum 
value of the value range will normally be shown. This 
is the value 4095 in the unscaled range and the 
specified upper limit in the scaled range.
If the input current is negative because the cables 
have been reversed, the measured value will be “0”.

If I

^ 21 mA or ^ –1 mA due to reversed poles, the 

diagnostics bit "Out-of-range" diagnostics bit will 
indicate an out-of-range value (see page 26).

mA

21

19.99

15

10

5

0

400

800

C00

FFF

1024

2048

3072

4095

hex

dec.

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Analog Value 
Representation

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Inputs for 4 to 20 mA

Figure 12:  Value range for current inputs 4 to 20 mA

If the input current exceeds 20 mA, the maximum 
value of the value range will normally be output. This 
is the value 4095 in the unscaled range and the 
specified upper limit in the scaled range. 

A current of 4 mA will cause the value 820 (334 hex) 
to be output in the unscaled range and the lower limit 
value in the scaled range.

If the input current drops below 4 mA or is negative 
due to the reversing of the cables, the value 820 
(334 hex) will be output as a constant or the lower 
limit value will be shown if the range is scaled.

mA

21

19.99

15

10

5

, 4

3

334 400

800

C00

FFF

1024

2048

3072

4095

820

0

hex

dec.

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Analog/digital conversion

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Two error messages may be output with inputs 
configured with a measuring range of 4 to 20 mA:

With out-of-range values of 

^ 21 mA or ^ –1 mA 

the "Out-of-range value” diagnostics bit will 
change to “1” (see page 26). The input current 
can be negative if the cables are reversed.

In the event of a wire breakage with values 
% 3 mA the "Wire breakage" diagnostics bit will 
change to “1” (see page 26).

Output value range

If faulty entries cause the output of values outside of 
the permissible range, the appropriate maximum of 
minimum value will be output.

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Analog Value 
Representation

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Figure 13:  Value range for current outputs 0 to 20 mA

Figure 14:  Value range for current outputs 4 to 20 mA

mA

19.99

15

10

5

400

800

C00

FFF

1024

2048

3072

4095

0

hex

dec.

mA

19.99

15

10

5

0

800

C00

FFF

2048

3072

4095

334 400

1024

820

4

hex

dec.

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Analog/digital conversion

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Scaling

A scaled range can be assigned to the the digital 
value range. This allows the specific value for the 
application to be scanned or output directly.
The scaled values are based on the value range from 
0 to 4095 with an input/output current of 0 to 
19.99 mA or from 820 to 4095 with a current of 4 to 
19.99 mA.
If, for example, a scaled range from –32768 to 32767 
was selected for the input signal 0 to 19.99 mA, the 
scaled range will be divided into steps of 16.
Example: 

Figure 15:  Scaling the input signal

65535

4095

----------------

16

=

19.99

mA

4095

0

1

– 32768

2048

0

0

– 32752

4094

32751 32767

Difference: 16

decimal value

scaled value

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Analog Value 
Representation

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The following examples show the scaling from 0 to 
200 with an input value of 0 to 20 mA and 4 to 20 mA.

The maximum scaled range can be defined from 
–32768 to +32767.
The difference between the higher and lower value 
must be at least “1”.
The higher value must always be "more positive" 
than the lower one.
Examples:

Example 1:
Scaling of value range 0 to 4095. In this example “0” 
was used for the lower value and 200 for the higher. 

Figure 16:  Scaling the input signal 0 to 19.99 mA from 
0 to 200

Lower value

Higher value

–1

0

0

1

2

3

–16

4

19.99

mA

4095

0

0

0

200

decimal value

scaled value

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Analog/digital conversion

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Calculating the analog value

y = Required analog value
B = Selected range, 0 to 200 = 200
z = Specified digital value (0 to 200)

Calculating the digital value

x = Required digital value (0 to 200)
B = Selected range, 0 to 200 = 200
v = Specified analog value

Example 2:
Scaling of value range 820 to 4095. In this example 
“0” was used for the lower value and 200 for the 
higher. 

Figure 17:  Scaling the input signal 4 to 19.99 mA from 
0 to 200

3 4096 3 0.00488

B

--------------------------------------------------------

y [mA]

=

3 B

0.00488 

3 4096

--------------------------------------------

x

=

19.99

mA

4095

0

200

0

4

19.99

mA

4095

0

820

200

0

4

decimal value

scaled value

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Analog Value 
Representation

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Calculating the analog value

y = Required analog value
B = Selected range, 0 to 200 = 200
z = Specified digital value (0 to 200)

Calculating the digital value

x = Required digital value (0 to 200)
B = Selected range, 0 to 200 = 200
v = Specified analog value

The digital values are shown in 16-bit format.

Positive values: 0 to 7FFF
Negative values: 8000 to FFFF

decimal

hexadecimal

0

0000

1

0001

.

.

.

.

.

.

32767

7FFF

–32768

8000

.

.

.

.

.

.

–2

FFFE

–1

FFFF

3 0.00488 3 3276

B

--------------------------------------------------------

4

+

y [mA]

=

(v

4)

3 B

3276

30.00488

----------------------------------------

x

=

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Appendix

Technical Data

General

Standards, regulations

EN 61 131-2, EN 50 178

Ambient temperature

0 to 55 °C

Storage temperature

–25 to +70 °C

Weight

approx. 300 g

Shock resistance

15 g, 11 ms

Vibration resistance

Const. constant 1 g, f = 0 to 
150 Hz

Device mounting

Snap-fit on top-hat rail or 
mounting plate

Rated insulation voltage

600 V AC

Degree of protection

IP 20

Terminals

Plug-in screw terminal

Terminal cross-section

Flexible with ferrule

0.22 to 1.5 mm

2

(AWG 23 to 16)

solid

0.22 to 2.5 mm

2

(AWG 23 to 13)

Configuration

With expandable PS 4 compact 
PLCs

Max. number per PS 4-200/300, 
EM 4-204-DX1

2

Isolation

Between LE bus and analog I/O

Yes

Insulation between I/O

no

Cable to sensors or actuators

Screened twisted pair
cable

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Appendix

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Inputs

Number of current inputs

4

Measuring ranges

0 to 20 mA, 4 to 20 mA

Resolution

12 Bit

Total error

Normally 0.4 % (0 to 55 °C)

Scanning

Without averaging, 
without scaling 3 ms
without averaging, 
with scaling 4 ms

Averaging

yes, from 8 ms to 1 s

Input impedance

50

 V

Error signals

Wire breakage
out-of-range value

Outputs

Number of current outputs

2

Measuring ranges

0 to 20 mA, 4 to 20 mA

Resolution

12 Bit

Total error

Normally 0.4 % (0 to 55 °C)

Load resistance

max. 500 

V

General EMC specifications for automation equipment

Emission

EN 55 011/22 Class A

Interference immunity

ESD

EN 61 000-4-2

Contact discharge
Air discharge

4 kV
8 kV

RFI

EN 61 000-4-3

AM/PM

10 V/m

Burst

EN 61 000-4-4

Mains/digital I/O
Analog I/O, fieldbus

2 kV
1 kV

Surge

EN 61 000-4-5

Digital I/O, asymmetrical
Mains DC, asymmetrical
Mains DC, symmetrical
Mains AC, asymmetrical
Mains AC, symmetrical

0.5 kV
1 kV
0.5 kV
2 kV
1 kV

Immunity to line-

conducted
interference

EN 61 000-4-6

AM

10 V

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Index

A
Analog cables  ................................................................ 14
Analog/digital conversion  .............................................. 31

C
Connecting ..................................................................... 14

Analog cables ............................................................. 14
PS 4  ............................................................................ 14

Connection ..................................................................... 12

Overview ..................................................................... 12

Contact .......................................................................... 16

E
EMC regulations  ............................................................ 11
Emission ......................................................................... 11

F
Features ........................................................................... 5

G
Grounding the screen for analog cables ........................ 17

H
Heat ................................................................................ 16

I
Immunity ........................................................................ 11
Installing in a control cabinet  ........................................... 9

M
Mounting .......................................................................... 7

Control cabinet ............................................................. 9
Fixing feet  ..................................................................... 8
On top-hat rail  .............................................................. 7

N
Number, I/O  ..................................................................... 5

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Index

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09/99 AWB 2700-1331 GB

P
Plug-in screw terminal .................................................... 10
PS 4  ................................................................................ 14

R
Requirements

Software ........................................................................ 6

Resolution ........................................................................ 5

S
Setup ................................................................................ 6
Software configuration  ................................................... 23
Step width, calculation  ................................................... 32

T
Terminal .......................................................................... 16

Z
ZB ................................................................................... 16


Document Outline