FISCHER DE45 R/S Series User manual

II Ex nA IIC T4 Gc3G
II Ex tc IIIB T125 °C Gc3D
Operating manual
DE45 ... R/S
Digital 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
09005703 • BA_EN_DE45_ATEX_LCD • Rev. ST4-I • 07/22 *09005703*

| Masthead FISCHER Mess- und Regeltechnik GmbH
2/40 BA_EN_DE45_ATEX_LCD
Masthead
Manufacturer: FISCHER Mess- und Regeltechnik GmbH
Bielefelderstr. 37a
D-32107 Bad Salzuflen
Telephone: [phone]
Telefax: [phone]
eMail: [email protected]
web: www.fischermesstechnik.de
Technical editorial team: Documentation representative: T. Malischewski
Technical editor: R. Kleemann
All rights, also those to the translation, reserved. No part of this document may
be reproduced or processed, duplicated or distributed using electronic systems
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 2014

FISCHER Mess- und Regeltechnik GmbH Table of Content
BA_EN_DE45_ATEX_LCD 3/40
Table of Content
1 Safety instructions.......................................................................................................... 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............................................................................................................ 6
2 Product and functional description............................................................................... 7
2.1 Use as intended ..................................................................................................................... 7
2.2 Part designations.................................................................................................................... 8
2.3 Function diagram.................................................................................................................... 8
2.4 Design and mode of operation ............................................................................................... 9
3 Installation ....................................................................................................................... 10
3.1 General................................................................................................................................... 10
3.2 Process connection ................................................................................................................ 10
3.3 Electrical connection .............................................................................................................. 11
4 Commissioning ............................................................................................................... 13
4.1 General................................................................................................................................... 13
4.2 Control Elements.................................................................................................................... 13
4.3 Menu levels ............................................................................................................................ 15
5 Maintenance .................................................................................................................... 28
5.1 Maintenance........................................................................................................................... 28
5.2 Maintenance........................................................................................................................... 28
5.3 Transport ................................................................................................................................ 28
5.4 Service ................................................................................................................................... 28
5.5 Disposal.................................................................................................................................. 28
6 Technical data ................................................................................................................. 29
6.1 Input variables ........................................................................................................................ 29
6.2 Output parameters ................................................................................................................. 29
6.3 Auxiliary energy...................................................................................................................... 30
6.4 Measuring accuracy ............................................................................................................... 30
6.5 Application conditions............................................................................................................. 31
6.6 Construction design................................................................................................................ 31
6.7 Display and operating interface.............................................................................................. 33
7 Order Codes .................................................................................................................... 34
7.1 Device specification................................................................................................................ 36
7.2 Accessories ............................................................................................................................ 36
8 Attachments .................................................................................................................... 37

1 | Safety instructions FISCHER Mess- und Regeltechnik GmbH
4/40 BA_EN_DE45_ATEX_LCD
1 Safety instructions
1.1 General
This operating manual contains basic instructions for the installation, operation
and maintenance of the device that must be followed without fail. It must be
read by the installer, the operator and the responsible specialist personnel be-
fore installing and commissioning the device.
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.
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:

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• evident damage to the instrument
• failure of the electrical circuits
• longer storage outside the approved temperature range.
• considerable strain due to transport
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 | Safety instructions FISCHER Mess- und Regeltechnik GmbH
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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).
1. 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).
1. 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).
1. Avoid danger by observing the valid safety regulations.
NOTICE
Note / advice
This indicates useful information of advice for efficient and smooth operation.

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2 Product and functional description
2.1 Use as intended
The DE45 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 DE45 ## 00 ### KWDL # 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 Dc
-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 DE45 ## 00 ### KWDM # RS#### are suitable as
'Electrical equipment for use in potentially explosive areas, Zone 2 - Gases and
vapours.
Designation as per Directive 2014/34/EU:
II 3G Ex nA IIC T4 Gc
-10 °C ≤ T ≤ 60 °C
amb

2 | Product and functional description FISCHER Mess- und Regeltechnik GmbH
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2.2 Part designations
1
23
4
5
6
78
Fig.1: Part designations
1 Membrane keyboard 5 M12 connector 2 (4-pin, male)
2 LC display 6 M12 connector 1 (5-pin, male)
3 Casing lid 7 Process connection (-)
4 Lower part of casing 8 Process connection (+)
2.3 Function diagram
21 3
4
5
6
7
Fig.2: Function diagram DE45_LCD
1 Sensor element 5 LC display
2 Signal processing 6 Analogue output
3 Switching outputs 7 Microcontroller
4 Membrane keyboard

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2.4 Design and mode of operation
The device is based on a piezo-resistive sensor element that is suitable for
measuring overpressure, underpressure and differential pressure. The pres-
sures to be compared directly act on a silicon diaphragm equipped with piezo-
resistive resistors.
When the pressure is equal, the measuring diaphragm is in its idle state. In the
event of differential pressure, the diaphragm is moved toward the lower pres-
sure which changes the resistance of the attached resistors. This change is
evaluated by the device's electronics and transformed into the display, switch
contacts or an optional output signal.
The optional output signal can be dampened, spread, inverted and transformed
via a table function even if it is non-linear.

3 | Installation FISCHER Mess- und Regeltechnik GmbH
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3 Installation
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
wsparks being generated on impact.
winvalidation of the protection class of the casing.
1. This can be avoided by attaching protective cover,
2. a protective casing or
3. 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 the suitability of the instrument for the media that is to be measured.
• Maximum pressures must be observed (cf. Tech. data)
CAUTION
Do not blow into the pressure connections.
This can damage the pressure sensor.
Fig.3: Process connection
The pressure measuring lines must be installed on a gradient so that no water
pockets for gas measurements can be created. If the required incline is not
reached, water filters need to be installed at suitable points.
The pressure sensing lines need to be kept as short as possible and installed
without sharp bends to avoid interfering delay times.
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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If the pressure sensing lines are already pressurised at the time of commission-
ing, zero-point control and adjustment cannot be performed. In such cases, the
device should be only connected to the mains without the pressure sensing
lines.
3.3 Electrical connection
3.3.1 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)
• 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.
3.3.2 3-wire connection
The device is connected as follows in a 3-wire switch:
The connection "Signal ground“ (-Sig) is connected internally to the supply
ground. It only serves as the ground connection for the output signal. This
means that the output signal is free of interference levels on the power supply
lines.
The supply voltage (24 V DC) may not exceed 32 V DC. The supply circuit must
be protected by a slow 200 mA fuse.
Reception
Delivery
AC
DC
Sensor
Signal
+Ub
- Ub
- Sig
+Sig
+Ub
- U b
p1
3
2
4
200 mAT
Fig.4: 3L-switch with internal bridge

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Connector 1: Supply and output signal
Fig.5: M12 Plug 5-pin
Pos Description Cable colour
A Coding A
B Internal bridge
1 +UbSupply brown
2 -Sig Signal white
3 -UbSupply blue
4 +Sig Signal black
5 n.c.
Connector 2: Switching outputs
Fig.6: M12 Plug 4-pin
Pos Description Cable colour
A Coding A
1 SP1 Switch point 1 (no) brown
2 SP2 Switch point 2 (no) white
3 SP2 Switch point 2 (com) blue
4 SP1 Switch point 1 (com) black
3.3.3 Ground connection
WARNING
Static electricity
The case must be equipped with an earth connection on the side to reduce the
surface resistance.
Ground connection
Fig.7: Ground connection
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 Control Elements
LC display
Fig.8: DE45 LCD display
1 LCD with back lighting 4 Unit
2 Measurement display 4…6 digits 5 Bar chart display
3 Status display of the switch
points
6 Keyboard
In normal mode, the current measured value is shown on a 4-digit LC display.
To show very large values, it is possible to switch to a 5 or 6-digit presentation
(see Parameter MB decimal place).
Fig.9: Display SP1 SP2
The unit is shown on the right of the display. If the device is equipped with con-
tacts, a closed contact is always symbolised by an inverted text "SP1" or "SP2".
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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4.2.1 Keyboard
Fig.10: 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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4.3 Menu levels
The menu levels are structured as follows:
Menu Level
Switch points
Menu Level
Input
Menu Level
Measuring
Menu Level
Output
Menu Level
Function
Menu Level
Display
Menu Level
System
Reception
Output
Output
Menu level
Quit
Menu level
Quit
Fig.11: Menu levels
The following tables provide an overview of the parameters of the individual
menu levels. In the Menu Level Systemyou can change to the respective na-
tional language using the language parameter. You can see which languages
are supported there.

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4.3.1 Menu Level Switch points
Parameter name Description Value range
SP1 On Switch point 1 On MRS-50% … MRE+50%
SP1 Off Switching point 1 off MRS-50% … MRE+50%
SP1 Delay Switching point 1 delay 0…1800 s
SP1 Function Switching point 1 function NO, NC
SP2 On Switch point 2 On MRS-50% … MRE+50%
SP2 Off Switching point 2 off MRS-50% … MRE+50%
SP2 Delay Switching point 2 delay 0…1800 s
SP2 Function Switching point 2 function NO, NC
The two switch 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 switch
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 MRS – 50% to MRE + 50%. MRS stands for
measuring range start and MRE for measuring range end.
Example: Measurement range = 0 … 100 Pa
The value range for this measuring range is -50 Pa … +150 Pa.
Together, the two parameters SP1 On and SP1 Off determine the switch func-
tion of switch 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 switch 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 switch output 1. It is possible here to
define whether the contact should work as a open contact (NO) or a break con-
tact (NC).

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4.3.2 Menu Level Input
Parameter name Description Value range
Absorption Attenuation, damping 0…100 s
Offset corr. Offset correction ⅓ basic measuring
range
Zero-pt. wind. Zero-point window ⅓ basic measuring
range
If there are unsteady pressure readings during operation, you can use the para-
meters Absorption and Zero-pt. wind. to stabilise the reading and the output
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 pressure jumps in the range 0.0 to 100 s.
NOTICE
Response time
At maximum damping it can take over 2 minutes until the pressure jump from
the nominal pressure 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 pressure leaves the set window.
When twice the window value is reached, the measuring pressure and the dis-
play correspond again. This avoids jumps in the display.
Differential pressure
Display value
-x-2x x 2x
Zero-point window
Fig.12: Zero-point window
It makes sense to set the Offset (zero-point displacement) if, without differential
pressure (remove measuring line), the display shows a value that is not zero.
Before the offset correction, the zero-point window must be set to zero.
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.

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4.3.3 Menu Level Measuring
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 bar, mbar, Pa, kPa,
MPa, psi, InWc,
mmWs, mmHg
Limit Measuring range limit yes, no
The transmitter output signal primarily depends on the sensed pressure. How-
ever, you have the option of adjusting the output signal to a large extent to suit
your requirements.
NOTICE
Adjustment of the output signal
The basic measuring range (indicated on the type label) and the type of output
signal (voltage / current) are not variable.
The parameters MB start and MB end initially define the two pressures
between which the output signal will change at all. Both values are adjustable
across the entire basic measuring range. The set values also refer to the pres-
sure in the respective unit. However, the signal values (current / voltage) for
‘Start of measuring range’ and ‘End of measuring range’ are fixed.
If MB start is smaller than MB end, this is called an increasing characteristic
curve; the output signal increases as the pressure increases.
If MB end is smaller than MB start, this is a decreasing characteristic curve and
the output signal decreases as the pressure increases.
The difference between the values MB start and MB end must be at least 25 %
of the basic measuring range.
You can select a unit other than the unit of the basic measuring range with the
parameter Unit. The user should remember however that not every unit is suit-
able. The conversion is automatic.
The parameter Limit allows the display, output and switching points to be lim-
ited to the range between Start of measuring range and End of measuring
range. This makes sense when content is measured to avoid "negative con-
tents". If Limit is set to "no", those measured values that are greater or smaller
than the end values are shown.

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4.3.4 Menu Level Output
Parameter name Description Value range
min. output min. output
0.0 … 21.0 mA or
0.0 … 11.0 V
max. output max. output
Error signal Measuring range unit
The parameters min. output, max. output and error signal define the limits of
the output signal that may not be undercut or exceeded regardless of the pres-
sure. The limit values take priority over the range defined by the MB start and
MB end parameters! These parameters primarily serve to prevent error mes-
sages in downstream systems caused by brief overstepping of measuring
ranges.
The parameter min. output is usually only used for devices with an output sig-
nal 4…20 mA because frequently values of below 3.8 mA are evaluated as er-
ror signals.
The max. output value can be used for the voltage and current to limit the max-
imum value.
The value defined via the parameter Error signal is issued if the device detects
an internal error and can no longer work correctly. It should be noted here that
not all potential errors and faults can be detected by the device itself.
4.3.5 Menu Level Function
The Function menu level is a variable menu whose appearance depends on the
value of the Function parameter. There are linear, square rooted and table func-
tions
Linear function
The input signal is linear before being sent to the display and the output. The
range defined in the menu "Measuring" serves as the measuring range. If the
function LINEAR is active, the other menu items are cancelled.
Parameter name Description Value range
Function Function Value = linear
Square rooted function
Here, the input signal is square rooted before being sent to the display and the
output. This is necessary e.g. for flow measurements with differential pressure.
A free unit can be defined for the display. To do this, the start and end of the
display range and the number of decimal points are defined. It is also possible
to define the unit with 4 characters.
Parameter name Description Value range
Function Function Value = square
rooted
MB decimal pl. Measuring range
decimal places
1234, 123.4, 12.34,
1,234, 12345, 123456
MB start Measuring range start -9999 … +9999
MB end Measuring range end -9999 … +9999
MB unit Measuring range unit 4 characters
The following section contains descriptions of the parameters MB decimal pl.,
MB start, MB end and MB unit to describe the table function.

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Tables function
This function allows free adjustment of the input variable to the display and out-
put via a table with up to 30 support points. A value pair comprising a measured
value and display value is issued for every support point.
NOTICE
Change of parameter
When switching from TABLE to another function, the table is initialised again
and the existing values are lost.
Parameter name Description Value range
Function Function Value = Table
MB decimal pl. Measuring range
decimal places
1234, 123.4, 12.34,
1,234, 12345, 123456
MB start Measuring range start -9999 … +9999
MB end Measuring range end -9999 … +9999
MB unit Measuring range unit 4 characters
No. of pairs Number of pairs n = 3…30
Value pair1 Value pair 1
MB-start … MB-end
Value pair2 Value pair 2
Value pair3 Value pair 3
∙∙∙
Value pair30 Value pair 30
The display range is defined with the parameters MB decimal pl., MB start and
MB end. The user can select the configuration freely.
Using the parameter MB decimal pl., it is possible to select between a 5 or 6-
digit presentation. The resolution is not increased. Only an extra zero or two
zeros are added. This serves the correct display of larger values. The measur-
ing range must be positive for the 6 digit presentation.
The MB unit gives the user the option of defining a completely independent
unit. Letters, numbers or special characters can be used. The unit can be max.
4 characters long.
If the function TABLE is selected, then it is also necessary to state the No. of
pairs. It is defined here how many pairs of values (support points) are used in
the table. A table is made up of at least 3, max. 30 support points.
NOTICE
Number of value pairs
If the number of value pairs is changed, the table is initialised again and the ex-
isting values are deleted.