FISCHER DE44 User manual

Operating manual
DE44 ... R/S
Digital 2-channel differential pressure switch/transmitter
with colour-change LCD
for explosive areas
Dust explosion protection zone 22, dry dusts
Gas explosion protection zone 2, gases and vapors
09005870 • BA_EN_DE44_LCD_ATEX • Rev. ST4-C • 07/17 *09005870*

| Masthead FISCHER Mess- und Regeltechnik GmbH
2 / 44 BA_EN_DE44_LCD_ATEX
Masthead
Manufacturer: FISCHER Mess- und Regeltechnik GmbH
Bielefelderstr. 37a
D-32107 Bad Salzuflen
Telefon: [phone]
Telefax: [phone]
eMail: [email protected]
web: www.fischermesstechnik.de
Technical editorial team: Documentation representative: S. Richter
Technical editor: R.Kleemann
All rights, also those to the translation, reserved. No part of these instructions
may be reproduced or processed, duplicated or distributed using electronic sys-
tems or any other form (print, photocopy, microfilm or another process) without
the written consent of the company FISCHER Mess- und Regeltechnik GmbH,
Bad Salzuflen.
Reproduction for internal use is expressly allowed.
Brand names and procedures are used for information purposes only and do
not take the respective patent situation into account. Great care was taken
when compiling the texts and illustrations; nevertheless, errors cannot be ruled
out. The company FISCHER Mess- und Regeltechnik GmbH will not accept any
legal responsibility or liability for this.
Subject to technical amendments.
© FISCHER Mess- und Regeltechnik GmbH 2016
Version history
Rev. ST4-A 07/16 Version 1 (first edition)
Rev. ST4-B 01/17 Version 2 New EU Directives (04/2016)
Rev. ST4-C 07/17 Version 3 (Correction)

FISCHER Mess- und Regeltechnik GmbH Table of Content
BA_EN_DE44_LCD_ATEX 3 / 44
Table of Content
1 Safety guidelines ............................................................................................................................................4
1.1 General .....................................................................................................................................................4
1.2 Personnel Qualification.............................................................................................................................4
1.3 Risks due to Non-Observance of Safety Instructions ...............................................................................4
1.4 Safety Instructions for the Operating Company and the Operator............................................................4
1.5 Unauthorised Modification ........................................................................................................................5
1.6 Inadmissible Modes of Operation .............................................................................................................5
1.7 Safe working practices for maintenance and installation work .................................................................5
1.8 Pictogram explanation ..............................................................................................................................5
2 Product and functional description ..............................................................................................................6
2.1 Use as intended........................................................................................................................................6
2.2 Function diagram with 2 switching outputs ...............................................................................................6
2.3 Function diagram with 4 switching outputs ...............................................................................................7
2.4 Design and mode of operation..................................................................................................................7
2.5 Part designations ......................................................................................................................................8
3 Installation and assembly..............................................................................................................................9
3.1 General .....................................................................................................................................................9
3.2 Process connection ..................................................................................................................................9
3.3 Electrical connections .............................................................................................................................10
4 Commissioning.............................................................................................................................................13
4.1 General ...................................................................................................................................................13
4.2 Configuration ..........................................................................................................................................13
4.3 Control Elements ....................................................................................................................................13
4.4 Menu levels.............................................................................................................................................16
5 Servicing .......................................................................................................................................................30
5.1 Wartung (maintenance) ..........................................................................................................................30
5.2 Transport ................................................................................................................................................30
5.3 Service....................................................................................................................................................30
5.4 Accessories ............................................................................................................................................30
5.5 Disposal ..................................................................................................................................................30
6 Technical data...............................................................................................................................................31
6.1 General ...................................................................................................................................................31
6.2 Input variables ........................................................................................................................................31
6.3 Output parameters..................................................................................................................................31
6.4 Measuring accuracy................................................................................................................................32
6.5 Auxiliary energy .....................................................................................................................................33
6.6 Application conditions .............................................................................................................................34
6.7 Construction design ................................................................................................................................34
6.8 Display and operating interface ..............................................................................................................38
7 Order Codes..................................................................................................................................................39
7.1 Accessories ............................................................................................................................................42
8 Attachments..................................................................................................................................................43
8.1 EU Declaration of Conformity .................................................................................................................43

1 | Safety guidelines FISCHER Mess- und Regeltechnik GmbH
4 / 44 BA_EN_DE44_LCD_ATEX
1 Safety guidelines
1.1 General
WARNING
This operating manual contains instructions fundamental to the installation, op-
eration and maintenance of the device that must be observed unconditionally. It
must be read by the assembler, operator and the specialized personnel in
charge of the instrument before it is installed and put into operation.
This operating manual is an integral part of the product and therefore needs to
be kept close to the instrument in a place that is accessible at all times to the re-
sponsible personnel.
The following sections, in particular instructions about the assembly, commis-
sioning and maintenance, contain important information, non-observance of
which could pose a threat to humans, animals, the environment and property.
The instrument described in these operating instructions is designed and manu-
factured in line with the state of the art and good engineering practice.
1.2 Personnel Qualification
The instrument may only be installed and commissioned by specialized person-
nel familiar with the installation, commissioning and operation of this product.
Specialized personnel are persons who can assess the work they have been
assigned and recognize potential dangers by virtue of their specialized training,
their skills and experience and their knowledge of the pertinent standards.
WARNING
For explosion-proof models the specialized personnel must have received spe-
cial training or instruction or be authorized to work with explosion-proof instru-
ments in explosion hazard areas.
1.3 Risks due to Non-Observance of Safety Instructions
Non-observance of these safety instructions, the intended use of the device or
the limit values given in the technical specifications can be hazardous or cause
harm to persons, the environment or the plant itself.
The supplier of the equipment will not be liable for damage claims if this should
happen.
1.4 Safety Instructions for the Operating Company and the Operator
The safety instructions governing correct operation of theinstrument must be
observed. The operating company must make them available to the installation,
maintenance, inspection and operating personnel.
Dangers arising from electrical components, energy discharged by the medium,
escaping medium and incorrect installation of the device must be eliminated.
See the information in the applicable national and international regulations.
Please observe the information about certification and approvals in the Tech-
nical Data section.
The instrument must be decommissioned and secured against inadvertent re-
operationif a situation arises in which it must be assumed that safe operation is
no longer possible. Reasons for this assumption could be:
• evident damage to the instrument
• failure of the electrical circuits
• longer storage outside the approved temperature range.
• considerable strain due to transport

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Repairs may be carried out by the manufacturer only.
A professional single conformity inspection as per DIN EN 61010, section 1,
must be carried out before the instrument can be re-commissioned. This inspec-
tion must be performed at the manufacturer's location. Correct transport and
storage of the instrument are required.
1.5 Unauthorised Modification
Modifications of or other technical alterations to the instrument by the customer
are not permitted. This also applies to replacement parts. Only the manufacturer
is authorised to make any modifications or changes.
1.6 Inadmissible Modes of Operation
The operational safety of this instrument can only be guaranteed if it is used as
intended. The instrument model must be suitable for the medium used in the
system. The limit values given in the technical data may not be exceeded.
The manufacturer is not liable for damage resulting from improper or incorrect
use.
1.7 Safe working practices for maintenance and installation work
The safety instructions given in this operating manual, any nationally applicable
regulations on accident prevention and any of the operating company's internal
work, operating and safety guidelines must be observed.
The operating company is responsible for ensuring that all required mainten-
ance, inspection and installation work is carried out by qualified specialized per-
sonnel.
1.8 Pictogram explanation
DANGER
Type and source of danger
This indicates a direct dangerous situation that could lead to death or serious
injury (highest danger level).
a) Avoid danger by observing the valid safety regulations.
WARNING
Type and source of danger
This indicates a potentially dangerous situation that could lead to death or ser-
ious injury (medium danger level).
a) Avoid danger by observing the valid safety regulations.
CAUTION
Type and source of danger
This indicates a potentially dangerous situation that could lead to slight or seri-
ous injury, damage or environmental pollution (low danger level).
a) Avoid danger by observing the valid safety regulations.
NOTICE
Note / advice
This indicates useful information of advice for efficient and smooth operation.

2 | Product and functional description FISCHER Mess- und Regeltechnik GmbH
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2 Product and functional description
2.1 Use as intended
The DE44 is a multi-functional switching unit with an optional transmitter output.
It is suitable for measuring overpressure, under-pressure and differential pres-
sure in gaseous media.
The unit is suitable as an electrical device for operation in potentially explosive
areas.
2.1.1 Explosion hazard area classification
Dust explosion protection
Devices with the order code DE44 ## ## ## # KW # L # S#### are suitable as
'Electrical equipment for use in areas with combustible dust', Zone 22 - dry
dusts.
Designation as per Directive 2014/34/EU:
II 3D Ex tc IIIB T125°C IP65
-10 °C ≤ T ≤ 60 °C
amb
WARNING
Static electricity
The case must be equipped with an earth connection on the side to reduce the
surface resistance.
Gas explosion protection
Devices with the order code DE46 DE44 ## ## ## # KW # M # R#### are suit-
able as 'Electrical equipment for use in potentially explosive areas, Zone 2 -
Gases and vapours.
Identification acc. to Directive 2014/34/EU:
II 3G Ex nA IIC T4
-10 °C ≤ T ≤ 60 °C
amb
2.2 Function diagram with 2 switching outputs
+
-
+
-
Channel 1 (P1)
Channel 2 (P2)
SP1
SP2
Sig 1
Sig 2
Δp1
Δp2
1,234
A
D
A
D
µC
þûÿ
D
A
D
A
Illustration1: Function diagram with 2 switching outputs

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2.3 Function diagram with 4 switching outputs
+
-
+
-
Channel 1 (P1)
Channel 2 (P2) Sig 1
Sig 2
Δp1
Δp2
SP1
SP2
1,234
A
D
A
D
µC
þûÿ
D
A
D
A
SP3
SP4
Illustration2: Function diagram with 4 switching outputs
2.4 Design and mode of operation
This switch unit is based on two piezo-resistor sensor elements that are suitable
for measuring over-pressure, under-pressure and differential pressure. The
pressure that is to be measured acts upon a silicone membrane that is
equipped with a resistor bridge.
This pressure-related movement of the diaphragm induces a change of resist-
ance, which is evaluated by the device's electronics and transformed into sig-
nals for the display and two or four switch contacts. There are also (optional)
two transmitter outputs available. The outputs are permanently assigned to the
input channels.
• Channel 1 (P1) → Output 1 (Sig 1)
• Channel 2 (P2) → Output 2 (Sig 2)
An output signal between the uniform signals 0…20mA, 4…20mA and
0…10V can be selected. Both outputs can be dampened, spread and inver-
ted. Both outputs can also be square-rooted and transformed via a table func-
tion even if it is non-linear.
In the case of flow measurements, larger values with 5 or 6 digits can be shown
(see also Parameter decimal place measuring range).
a) Model with 2 switching outputs
The switching outputs can be assigned to the input channels by means of con-
figuration:
• Channel 1 (P1) → SP1, SP2
• Channel 1 (P1) → SP1
Channel 2 (P2) → SP2
• Channel 2 (P2) → SP1, SP2
b) Model with 4 switching outputs
The switching outputs are permanently assigned to the input channels as fol-
lows:
• Channel 1 (P1) → SP1, SP2
• Channel 2 (P2) → SP3, SP4

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2.5 Part designations
2
1
3
17
5
6
8
7
10
9
12
11
13
15 16
146
5
4
10
9
12
11
2
1
313
DE44 ... R
Zone 2
DE44 ... S
Zone 22
1818
Illustration3: DE44_LCD_Overview
1 Foil keypad 2 LC display
3 Casing lid 4 Lower part of casing
5 Circuit diagram 6 Wall bracket
7 M12 plug 1 (plastic) 8 M12 plug 2 (plastic)
9 Process connection P1 (+) 10 Process connection P1 (-)
11 Process connection P2 (+) 12 Process connection P2 (-)
13 Type plate 14 Ground connection
15 M12 plug 1 (MS nickel-plated) 16 M12 plug 2 (MS nickel-plated)
17 Lower part of casing (metal) 18 ATEX code
Type plate
The presented type plates serve to show an example of the information shown.
The data shown is purely fictive, but does correspond to the actual conditions.
For more information, please see the order code at the end of these instruc-
tions.
with analogue output without analogue output
Marking Special propertiesOrder Codes
0 ... 6 mbar
0 ... 20 mA
0 ... 6 mbar
DE445353404KWDMW R0892
1405250.01.001
0 ... 6 mbar
0 ... 6 mbar
DE445353400KWDLW S0891
1405250.02.001
Serial number
Technical data
ATEX code zone 2 ATEX code zone 22
Illustration4: DE44_LCD Type plate

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3 Installation and assembly
3.1 General
The device is designed for installation onto flat assembly plates. For screw con-
nection to the assembly plate, the device features four assembly bores on its
back, which can be used for Ø 3.5 mm tapping screws.
Optionally, the device can be delivered with a wall-mounting plate. This is also
available as accessory.
At the factory, the device is calibrated for vertical installation, but the installation
position is arbitrary. For any installation positions that are not vertical, the zero-
point signal can be corrected via the installed offset correction.
The enclosure protection type IP 65 is only guaranteed, if a suitable power sup-
ply cable is used (see accessories).
If the device is intended for outdoor use, we recommend permanently protecting
the membrane keypad against UV radiation and using a suitable enclosure or at
least the erection of a sufficiently dimensioned canopy as a protection measure
against constant rain or snow.
WARNING
Falling objects
The operator must ensure that any falling objects cannot collide with the in-
stalled unit. Steps must be taken to prevent
üsparks being generated on impact.
üthe protection class of the casing is no longer guaranteed.
a) This can be avoided by attaching protective cover,
b) a protective casing or
c) a similar element.
3.2 Process connection
• By authorized and qualified specialized personnel only.
• The pipes need to be depressurized when the instrument is being connec-
ted.
• Appropriate steps must be taken to protect the device from pressure surges.
• Check that the device is suitable for the medium being measured.
• Maximum pressures must be observed (cf. Tech. data)
CAUTION
Do not blow into the pressure connections.
This may damage the sensor.
P1(+)
P1(-)
P2(+)
P2(-)
Illustration5: Process connection
The pressure lines must be installed at an inclination so that when fluids are
measured no air pockets are created or when measuring gases, no water pock-
ets are created. If the required inclination is not reached, water or air filters must
be installed at suitable places.
The pressure lines must be kept as short as possible and installed without any
tight bends to avoid delays.
The differential pressure inputs are marked with P1 and P2.
The pressure connections are marked with (+) and (-) symbols on the device.
When the differential pressure is measured, the higher pressure is connected to
the (+) side and the lower pressure to the (-) side.

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3.3 Electrical connections
WARNING
Operation in areas at risk of explosion
If operated in explosive areas, the electrical data of the unit and the valid local
regulations and guidelines for the installation and operation of electrical systems
in explosive areas must be observed (e.g. DIN EN 60079-14)
• By authorized and qualified specialized personnel only.
• When connecting the unit, the national and international electro-technical
regulations must be observed.
• Disconnect the system from the mains, before electrically connecting the
device.
• Install the consumer-adapted fuses.
• Do not connect the connector if strained.
If units are used in potentially explosive areas, the personnel must receive addi-
tional training or briefings or have a permit to work ion explosion-protected units
in potentially explosive systems.
The nominal supply voltage and the permissible range can be found in the tech-
nical data.
The admissible load / resistance is stated in the technical data.
Connection wiring
WARNING
Supply circuit
A CE-conform mains adapter with a slow 200 mA fuse only may be used in the
power supply circuit.

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The device is connected as follows in a 3-wire switch:
p1
p2
Pressure Transmitter Supply
Output signal
Input signal
+Sig 2
+Ub
-Ub
+Ub
-Ub
+Sig 1
+-+-
1 2
230 VAC
24 VDC
200 mA
Illustration6: 3L connection
Electrical connection
Connector 1
Illustration7: M12 plug 5-pin
Pin Signal name Cable colour
1Supply +Ubbrown
2Output 2 +Sig2 white
3Supply -Ubblue
4Output 1 +Sig1 Black
5unused green/yellow
ACoding A
Table1: Supply and output signal
a) Model with 2 switching outputs
Connector 2
Illustration8: M12 plug 4-pin
Pin Signal name Cable colour
1Switching output 1 SP1 brown
2Switching output 2 SP2 white
3Switching output 2 SP2 blue
4Switching output 1 SP1 Black
ACoding A
Table2: Two switching outputs
b) Model with 4 switching outputs
Connector 2
Illustration9: M12 plug 8-pin
Pin Signal name Cable colour
1Switching output 1 SP1 white
2Switching output 1 SP1 brown
3Switching output 2 SP2 green
4Switching output 2 SP2 yellow
5Switching output 3 SP3 grey
6Switching output 3 SP3 pink
7Switching output 4 SP4 blue
8Switching output 4 SP4 red
ACoding A
Table3: Four switching outputs

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3.3.1 Ground connection
WARNING
Static electricity
The case must be equipped with an earth connection on the side to reduce the
surface resistance.
Ground connection
Illustration10: Ground connec-
tion
Only devices for operation in potentially explosive areas with combustible, Zone
22 – Dry dusts have an earth connection on the left-hand side.
The housing is made of a non-conductive plastic. To reduce its surface resist-
ance, a metal layer has been applied in an evaporation process. To discharge
any static charging (e.g. caused by wiping), the housing must be earthed.

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4 Commissioning
4.1 General
All electrical supply, operating and measuring lines, and the pressure connec-
tions must have been correctly installed before commissioning. All supply lines
are arranged so that there are no mechanical forces acting on the device.
Check that the pressure connections do not leak before commissioning.
4.2 Configuration
During commissioning there are a number of setting options that allow the
device to be adapted to the measuring point and measuring task. To facilitate
the input, the individual parameters are placed into groups in so-called menu
levels.
Depending on the device model some menu items are not available. For in-
stance, no switch points can be set on a device without contacts.
All the device settings can be made easily on the PC using the PC adapter. You
will need a EU03 Transmitter PC Interface and the associated software Trans-
Para for this. For more details, please refer to the Accessories section. The
TransPara software makes all parameters directly visible and accessible. Also,
the entire configuration can be loaded, saved and documented as a printout.
4.3 Control Elements
4.3.1 LC display
In normal mode, the current measured value of an input channel is shown on a
4-digit LC display. The corresponding input channel is displayed (channel dis-
play). However, both measured values of the input channels can be shown at
the same time. To show very large values, it is possible to switch to a 5 or 6-di-
git presentation (see Parameter MB decimal place).
Various colours can be selected for the back lighting. Depending on the meas-
ured value, the colour of the back lighting can be automatically changed. This
can be used e.g. to depict good/poor differences. The back lighting can also be
deactivated.
The measured value can also be shown in a bar chart. The measured value is
also shown in smaller pictures as a number.
During the programming, the menu items and the associated parameters are
shown on the display. The device continues to function whilst the parameters
are being set; apart from one exception, the changes come into effect instantly.
The exception here is a change of switching times - here the previously valid
time must have run down.

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a) Model with 2 switching outputs
1
2 3
4
5
6
Display: Measured value
Display: Bar chart
Illustration11: LC display (2 switching outputs)
Illustration12: LC display 2SP
The unit is shown to the right of the measured value. If the device is equipped
with contacts, a closed contact is always symbolised by an inverted text "SP1"
or "SP2". One exception is the 1-channel bar chart diagram. Here, the switching
points are symbolised with simple numbers "12".
b) Model with 4 switching outputs
1
2 3
4
5
6
Display: Measured value
Display: Bar chart
3
Illustration13: LC display (4 switching outputs)
1 LCD with back lighting 4 Unit
2 Measurement display 4…6 digits 5 Channel display
3 Status display of the switch
points
6 Keyboard
Illustration14: LC display 4SP
The unit is shown to the right of the measured value. If the device is equipped
with contacts, a closed contact is always symbolised by an inverted text "SP1",
"SP2", "SP3" "SP4". One exception is the 1-channel bar chart diagram. Here,
the switching points are symbolised with simple numbers "1234".

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4.3.2 Keyboard
Illustration15: Operating keys [LC display]
1 Page down menu Reduce value
2 Call up menu Save value
3 Page up menu Increase value
The individual menu items and parameters can be displayed using the buttons
þ
and
ÿ
. The respective menu item is selected or the parameters for making
changes are called up via the button
û
.
If a parameter can be changed, the display flashes. The change is made via the
buttons
þ
and
ÿ
. The value is saved with the button
û
.
To leave a menu level or the entire menu, select the parameter "Menu level
Quit" and press
û
.
Example: Switch-on point set switchpoint 1
In normal mode, press the button
û
to enter the menu. The menu level Switch
points appears. Press the enter key
û
again to call up the display parameter.
The first parameter SP 1 On is displayed. To change this parameter, press the
button
û
again.
The device jumps to the input:
• The parameter is stated in the 1st line.
• The value that is to be changed is shown in the 2nd line, the display flashes.
• The input limits are displayed in the 3rd line (if there is one).
The required value is set with the buttons
þ
and
ÿ
and then confirmed with
û
.

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4.4 Menu levels
The menu levels are structured as follows:
End
menu level
Menu Level
Switch points
Menu Level
Input
Menu Level
Measuring
Menu Level
Output
Menu Level
Function
Menu Level
Display
Menu Level
System
End
menu level
Reception
Outlet
Outlet
Menu level
Function 2
Illustration16: Menu levels
The following tables provide an overview of the parameters of the individual
menu levels. In the System menu level you can change to the respective na-
tional language using the Language parameter. You can see which languages
are supported there.

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4.4.1 Menu Level Switch points (2SP)
NOTICE!This menu only appears on models with two switching outputs.
Parameter name Description Value range
SP1 On Switch point 1 On MBA-50% … MBE+50%
SP1 Off Switching point 1 off MBA-50% … MBE+50%
SP1 Delay Switching point 1 delay 0…1800 s
SP1 Function Switching point 1 function NO, NC
Assignment SP Channel assignment Channel 1, 2 and 1+2
SP2 On Switch point 2 On MBA-50% … MBE+50%
SP2 Off Switching point 2 off MBA-50% … MBE+50%
SP2 Delay Switching point 2 delay 0…1800 s
SP2 Function Switching point 2 function NO, NC
The two switching outputs are configured by four parameters respectively.
For the switch point 1 these are
•SP1 On
•SP1 Off
•SP1 Delay
•SP1 Function
Accordingly for switch point 2:
•SP2 On
•SP2 Off
•SP2 Delay
•SP2 Function
The function of the individual parameters is explained for both switch points us-
ing Switch point 1 as an example.
SP1 On defines the activation point, SP1 Off the deactivation point of switching
output 1. The values are shown in the valid unit and set accordingly. The values
are shown in the valid unit and set accordingly. Both parameters can be set in-
dependently over the entire value range.
The value range ranges from MBA – 50% to MBE + 50%. MBA stands for start
of measuring range and MBE for the end of the measuring range.
Example: Measuring range = 0 … 100 %
The value range for this measuring range is -50 % … +150 %.
Function of the switch points
Together, the two parameters SP1 On and SP1 Off determine the switch func-
tion of switching output 1:
• If SP1 On > SP1 Off, the output switches on, if the measured value ex-
ceeds SP1 On. It is only switched off again if the measured value SP1 Off is
undercut (hysteresis function).
• If SP1 On = SP1 Off, the output switches on if the measured value exceeds
SP1 On and off if the measured value undercuts the same value (SP1 Off).
• If SP1 On < SP1 Off, the output switches on, if the measured value lies
within these switch points: i.e:
SP1 On < Measured value < SP1 Off (window function).
SP1 Delay allows the reaction of the switching output to be delayed by between
0 and 1800 s. This parameter applies equally for switching on and off.
SP1 Function changes the function of the switching output 1. It is possible here
to define whether the contact should work as a open contact (NO) or a break
contact (NC).

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Assignment SP is used to define the input to which the contacts are assigned.
The following options are available:
• Channel 1
Both contacts are assigned to channel 1.
• Channel 1, channel 2
A contact is assigned to every channel.
Channel 1: SP1
Channel 2: SP2
• Channel 2
Both contacts are assigned to channel 2.
The unit and the input range are adapted accordingly when entering the switch
points.
4.4.2 Menu Level Switch points (4SP)
NOTICE!This menu only appears on models with four switching outputs.
Parameter name Description Value range
SP1 On Switch point 1 On MBA-50% … MBE+50%
SP1 Off Switching point 1 off MBA-50% … MBE+50%
SP1 delay Switching point 1 delay 0…1800 s
SP1 Function Switching point 1 function NO, NC
SP2 On Switch point 2 On MBA-50% … MBE+50%
SP2 Off Switching point 2 off MBA-50% … MBE+50%
SP2 delay Switching point 2 delay 0…1800 s
SP2 Function Switching point 2 function NO, NC
SP3 On Switch point 2 On MBA-50% … MBE+50%
SP3 Off Switching point 2 off MBA-50% … MBE+50%
SP3 delay Switching point 2 delay 0…1800 s
SP3 Function Switching point 2 function NO, NC
SP4 On Switch point 2 On MBA-50% … MBE+50%
SP4 Off Switching point 2 off MBA-50% … MBE+50%
SP4 delay Switching point 2 delay 0…1800 s
SP4 Function Switching point 2 function NO, NC
The switching outputs are configured by four parameters respectively.
For the switch point 1 these are
•SP1 On
•SP1 Off
•SP1 delay
•SP1 Function
The same correspondingly marked parameters apply for the switching point
2...4.
The function of the individual parameters is explained for all four switch points
using switch point 1 as an example.
SP1 On defines the activation point, SP1 Off the deactivation point of switching
output 1. The values are shown in the valid unit and set accordingly. The values
are shown in the valid unit and set accordingly. Both parameters can be set in-
dependently over the entire value range.

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The value range ranges from MBA – 50% to MBE + 50%. MBA stands for start
of measuring range and MBE for the end of the measuring range.
Example: Measuring range = 0 … 100 %
The value range for this measuring range is -50 % … +150 %.
Function of the switch points
Together, the two parameters SP1 On and SP1 Off determine the switch func-
tion of switching output 1:
• If SP1 On > SP1 Off, the output switches on, if the measured value ex-
ceeds SP1 On. It is only switched off again if the measured value SP1 Off is
undercut (hysteresis function).
• If SP1 On = SP1 Off, the output switches on if the measured value exceeds
SP1 On and off if the measured value undercuts the same value (SP1 Off).
• If SP1 On < SP1 Off, the output switches on, if the measured value lies
within these switch points: i.e:
SP1 On < Measured value < SP1 Off (window function).
SP1 Delay allows the reaction of the switching output to be delayed by between
0 and 1800 s. This parameter applies equally for switching on and off.
SP1 Function changes the function of the switching output 1. It is possible here
to define whether the contact should work as a open contact (NO) or a break
contact (NC).
The contacts are assigned to the inouts ad follows:
• Channel 1: SP1 and SP2
• Channel 2: SP3 and SP4
The unit and the input range are adapted accordingly when entering the switch
points.
4.4.3 Menu Level Input
Channel 1: Parameter name Description Value range
Absorption Damping 0…100 s
Offset corr. Offset correction ⅓ basic measuring
range
Zero-pt. wind. Zero-point window ⅓ basic measuring
range
Channel 2: Parameter name Description Value range
Absorption 2 Damping 0…100 s
Offset corr. 2 Offset correction ⅓ basic measuring
range
Zero-pt. wind.2 Zero-point window ⅓ basic measuring
range
The parameters for both channels are set in the same way. The following ex-
plains the parameters for the first channel as an example for both channels.
If there are unsteady measurement readings during operation, you can use the
parameters Damping and Zero-pt. wind. to stabilise the reading (and the out-
put signal).
The parameter Absorption functions like a capillary throttle. However, it only
acts on the display, output signal and switch points (if these exist) but not on the
measuring cell itself.
You can set the response time to measuring value jumps in the range 0.0 to
100 s.

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20 / 44 BA_EN_DE44_LCD_ATEX
NOTICE
Response time
At maximum damping it can take over 2 minutes until after a measurement jump
from 100% to 0% is also shown as zero in the display.
In many cases, unsteady readings are not a problem during normal operating
mode, but this is not true for the idle state, i.e. if a measured value of zero is ex-
pected. The parameter Zero-pt. wind. is designed to solve this. Its value
defines a range around zero at which the measured value is set to zero (see
fig.).
The display only stops showing zero when the measurement leaves the set win-
dow. When reaching double the value, the measured value and the reading
match again. This avoids jumps in the display.
Measured Value
Display value
-x-2x x 2x
Zero-point window
Illustration17: Zero-point window
It may be necessary to set the offset to correct the impact of the installation pos-
ition.
Select the Offset corr. parameter and correct the reading using the buttons
þ
or
ÿ
until zero is shown in the display.
When setting the offset, the current measured value is displayed. The zero-
point window is not active during the offset setting.
4.4.4 Menu Level Measurement
Channel 1: Parameter name Description Value range
MB start Measuring range start Basic measuring
range
MB end Measuring range end Basic measuring
range
Unit Measuring range unit
Limit Measuring range limit yes, no
Channel 2: Parameter name Description Value range
MB 2 start Measuring range start Basic measuring
range
MB 2 end Measuring range end Basic measuring
range
Unit 2 Measuring range unit