FISCHER DE44 User manual

*09005319* BA_EN_DE44_LCD Rev.F 04/12
*09005319*
1 Safety Instructions
1.1 General information
This operating manual contains detailed
information about the installation, opera-
tion and maintenance of the instrument.
This information must be observed and
read by the installer, operator and other skilled per-
sonnel prior to any installation and commissioning
of the instrument.
This operating manual forms part of the product and
must be kept in the immediate vicinity of the instru-
ment for easy access by the responsible personnel
at any time.
The following chapters, especially the instructions
on installation, commissioning and maintenance
contain important safety information, the non-
compliance of which may result in hazards to per-
sons, animals, environment and objects.
1.1 Personnel qualification
Only personnel trained in the installation, commis-
sioning and operation of this product may install
and operate the same.
Skilled personnel are persons who are able to judge
delegated work and possible hazards based on
their technical education, proficiency and experi-
ences, particularly due to their knowledge about the
applicable norms.
1.2 Risks of non-compliance with safety
instructions
Non-compliance with these safety instructions, in-
appropriate use of this product, and/or operation of
this product outside the limits specified for any of its
technical parameters, may result in harm to per-
sons, the environment or the system in which it is
installed.
The producer is not liable for any claims for damag-
es in such circumstances.
1.3 Safety instructions for operators
Safety instructions for the proper use of this product
must be followed. This information must be availa-
ble at all times to personnel responsible for installa-
tion, operation, maintenance and inspection of this
product.
Adequate steps must be taken to prevent the occur-
rence of hazardous conditions that can be caused
by electric energy and the convertible energy of the
process media and/or improper connec-
tion of the instrument. Detailed infor-
mation can be found in the relevant na-
Operating Manual
DE44
Digital 2-channel differential pressure switch/transmitter
with 4-digit color change LCD
Contents
1Safety Instructions
2Intended Applications
3Product Description and Function
4Installation
5Commissioning and Operating Manual
6Maintenance
7Transport
8Service
9Accessories
10 Disposal
11 Technical data
12 Dimensional drawings
13 Order codes
14 Declaration of conformity

Page 2
tional and/or international rules and regulations.
In Germany DIN EN, UVV apply, for industry-
specific applications regulations of DVGW, Ex, GL,
as well as the rules of the local authorities (EVUs in
Germany).
1.4 Forbidden modifications
Modification or other technical alteration of the de-
vice by the customer is not permissible. This also
applies for the use of spare parts. Any eventual
modifications/ variations will be carried out solely by
Fischer Mess- und Regeltechnik GmbH.
1.5 Impermissible operational modes
The operational dependability of the device is guar-
anteed only if it is used as intended. The device
version must be adapted to the medium used in the
system. The limiting values stated in the technical
data must not be exceeded.
1.6 Safety Considerations during Installa-
tion and Maintenance
The safety instructions stated in this manual, exist-
ing national regulations on accident prevention and
the internal rules and procedures on working, oper-
ation and safety of the operator are to be observed.
It is the responsibility of the operator to ensure that
only authorised and skilled technical personnel car-
ry out any required maintenance, inspection and in-
stallation works.
1.7 Explanation of symbols
WARNING!
...indicates a possible hazardous situ-
ation the non-observance of which
might result in hazards to humans, an-
imals, environment and objects.
INFORMATION!
…points out important information for
efficient and trouble-free operation.
TIP!
…points out useful recommendations
that are not necessarily required for
operation that might however be of
use in certain situations.
2 Intended Applications
•Air-conditioning technology
•Ventilation technology
•Environmental technology
•Monitoring roller band filters, suction systems
etc.
•Draw measurements on chimneys
•Flow and control pressure measurements
•Surface technology
The device can be used as a display and switch
device and has two independent differential pres-
sure inputs. It is suitable for measuring pressure,
underpressure and differential pressure for neutral
gaseous mediums.
3 Product Description and Function
3.1 Functional Sheme
3.2 Principles of Operation
The basis of this switch device is two piezoresistive
sensors.
The pressure to be measured, effects directly on a
silicon membrane equipped with a resistance
measurement bridge. The deflection caused by the
pressure effecting the membrane produces a
change in resistance which is assessed by the elec-
tronics integrated in the device and converted into
signals for display and switch contacts.
Two optionally available transmitter outputs can be
dampened, spread, inverted and transformed using
a table function, including non-linear.

Page 3
4 Installation
The device is intended for installation on level
mounting plates. To screw connect to the mounting
plate, the device has four mounting drill holes for
plate screws on the back Ø 3.5 mm.
The device can be supplied with a wall mounting
plate as an option (see order markings)
The device is adjusted for vertical installation in the
factory, but you can choose any installation posi-
tion. If you choose a different installation position to
vertical, the zero point signal can be corrected by
the installed zero point adjustment (see Initialisa-
tion/operating manual).
The housing protection class IP65 is only guaran-
teed if a suitable connection line is used.
If the device is planned for outdoor use, we recom-
mend using a suitable protective housing for per-
manent protection of the film keypad against UV ra-
diation and as a protective measure against heavy
rain and snow. The use of a sufficiently sized pro-
tective roof is required as a minimum.
4.1 Process connection
•By authorized and qualified specialized person-
nel only.
•The pipes need to be depressurized when the
instrument is being connected.
•Appropriate steps must be taken to protect the
instrument from pressure surges.
•Check the suitability of the instrument for the
media that is to be measured.
•Pay attention to maximum pressures.
•The tightness of the pressure connection lines
must be checked before initialization.
The pressure measuring 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 the (+)
and (-) symbols on the device. For differential pres-
sure measurements, the higher pressure on the (+)
side and the lower pressure on the (-) side of the
device are connected.
If, upon initialization, pressure is already applied to
the pressure measurement lines, no zero point test
and adjustment can be undertaken. In these cases,
the device should be connected electrically first.
4.2 Electrical connection
•By authorized and qualified specialized person-
nel only.
•The instrument must be connected electrically
in accordance with the relevant VDE guidelines
and the guidelines of the local EVU.
•Disconnect the system before attaching the in-
strument.
•Install the consumer-adapted fuses.
4.2.1 3-wire circuit
4.2.2 Plug 1: supply and output signal
4.2.3 Plug 2: switch outputs
5 Commissioning and
Operating Manual
All electrical supply, operating and measuring lines
and the pressure connections must have been cor-
rectly installed before commissioning. All connect-
ing pipes must be laid in a way that ensures that no
mechanical forces act on the instrument.
5.1 Configuration
There are a number of setting options to adjust that
device optimally to the measurement point and
measuring task upon initialization. In order to ar-
+
-
+
-
Δp1
Output
Transmitter
Evaluation e.g. PLC‘s
Voltage Supply
Input 1
+Ub
+Sig 1
-Ub
Output
230V ~
L
N
+Ub
-Ub
Input 2
+Sig 2
Δp1
BN
WH
BU
BK
SP1no
SP2com
SP2no
SP1com
Signal +Sig 2
Supply -Ub
Signal +Sig 1
n.c.
Supply +Ub
BN
WH
BU
BK

Page 4
range the entry more clearly, the individual parame-
ters are summarized in groups in the menu.
Depending on the current device version (current
output/voltage output/contacts), several menu
points are not available. This means you cannot set
any switch points for a device without contacts.
5.2 Display
The 4-digit LCD display represents the current
measurement value in the normal mode. If the de-
vice is equipped with contacts, a closed contact is
symbolized by the inverted text "SP1" or "SP2".
For devices with two input channels, both meas-
urement values are displayed at the same time. The
switch point symbols are displayed for the corre-
sponding channel.
In order to differentiate the measurement values be-
tween good and bad, the background lighting can
change the color. A fixed color can also be selected
as an alternative for the background color. The
background lighting is can also be switched off.
During parameterization, the menu point and the
corresponding parameter are shown on the display.
The device continues to work during parameteriza-
tion and therefore takes immediate effect with one
exception.
5.3 Operation
Operation takes place using the buttons:
•ÿ: reduce value
•û: Enter
•þ: increase value
From the normal mode, you reach the menu with
the ûbutton.
1
1
A password may need to be set after pressing the button û
(s.5.4.7).
You can display the individual menu points and pa-
rameters with the þand ÿbuttons.
With the ûbutton, the respective menu point is se-
lected or the parameters called up for change.
The display flashes if a parameter can be changed.
•The change is made with the buttons þand ÿ.
•The value is saved with the ûbutton.
Using the Menüebene beenden (end menu lev-
el) parameter, you return to the next highest
menu level. If no buttons are pressed, the device
automatically returns to the measurement value
display.
EXAMPLE: setting the switch points
Press the ûbutton in the normal mode to enter
the menu. The following display appears
In order to change the switch points, press the ûbutton again.
The first entry (SP1 here) of a parameter list is shown and the
set value below. With the buttons þor ÿ, you can now also set
other parameters. However, in order to change parameter SP1
for example press button û again.
•the parameter is stated in the first line once again,
•In the second line, the value to be changed is displayed and
the display flashes.
•In the 3rd line (if available), the entry limits are displayed.
With buttons þand ÿ,the required value is set and taken over
with û.
Menüebene
Schaltpunkte
SP1 Ein
+30.0 Pa
SP1 Ein
+30.0 Pa
-50.0 ... +150.0 Pa

Page 5
5.4 Menu (Original)
Schaltpunkte
Schaltpunkt 1 Ein
Schaltpunkt 1 Aus
Schaltpunkt 1 Verzögerung
Schaltpunkt 1 Funktion
Zuordnung des Schaltpunktes
Schaltpunkt 2 Ein
Schaltpunkt 2 Aus
Schaltpunkt 2 Verzögerung
Schaltpunkt 2 Funktion
Eingang
Dämpfung
Offsetkorrektur
Spannenkorrektur
Nullpunktfenster
bei 2kanaligen Geräten:
Dämpfung Kanal 2
Offsetkorrektur Kanal 2
Spannenkorrektur Kanal 2
Nullpunktkorrektur Kanal 2
Messung
Messbereich Anfang
Messbereich Ende
Einheit
Begrenzung
bei 2kanaligen Geräten:
Messbereich Anfang Kanal 2
Messbereich Ende Kanal 2
Einheit Kanal 2
Ausgang
min. Ausgang
max. Ausgang
Fehlersignal
Menu (Translation)
Switch points
Switch point 1 on
Switch point 1 off
Switch point 1 delay
Switch point 1 function
Allocation of the switch point
Switch point 2 on
Switch point 2 off
Switch point 2 delay
Switch point 2 function
Input
Dampening
Offset correction
Clamping correction
Zero point window
For 2-channel devices:
Dampening channel 2
Offset correction channel 2
Clamping correction channel 2
Zero point window channel 2
Measurement
Measurement range beginning
Measurement range end
Unit
Limitation
For 2-channel devices:
Measurement channel 2 beginning
Measurement channel range 2 end
Unit channel 2
Output
min. output
max. output
Error signal

Page 6
Funktion
Auswahl der Funktion
Bei Funktion RADIZIERT, TABELLE:
Anzahl Nachkommastellen „freie Einheit“
Messbereich Anfang „freie Einheit“
Messbereich Ende „freie Einheit“
„freie“ Einheit
bei Funktion TABELLE:
Anzahl der Wertepaare
Wertepaar 1
…
Wertepaar n
Display
bei Geräten mit 2 Eingangskanälen:
Zuordnung der Umschaltung
Farbe Auto1:
rot-grün Umschaltung
grün-rot Umschaltung
Hysterese
Verzögerung
Farbe Auto2:
rot-gelb Umschaltung
gelb-grün Umschaltung
grün-gelb Umschaltung
gelb-rot Umschaltung
Hysterese
Verzögerung
Farbe
Beleuchtungszeit
Kontrast
Bargraf
System
Software –Info
Konfig –Info
Passwort
Konfig. laden
Konfig. sichern
Statistik
Function
Selection of function
For ROOT EXTRACTED function, table:
Number of decimal places "free unit"
Measurement range beginning "free unit"
Measurement range end "free unit"
"free" unit
For function TABLE:
Number of value pairs
Value pair 1
…
Value pair n
Display
For devices with 2 input channels:
Allocation of changeover
Auto1 color:
red-green changeover
green-red changeover
Hysteresis
Delay
Auto2 color:
red-yellow changeover
yellow-green changeover
green-yellow changeover
yellow-red changeover
Hysteresis
Delay
Color
Lighting time
Contrast
Bar graph
System
Software –Info
Config –Info
Password
Load config.
Save config.
Statistics

Page 7
5.4.1 Menu level switch points
The two switch outputs are configured by four pa-
rameters
For switch point 1, these are:
SP1 Ein
SP1 Aus
SP1 Verzögerung
SP1 Funktion.
For switch point 2 correspondingly:
SP2 Ein
SP2 Aus
SP2 Verzögerung
SP2 Funktion.
SP1 Ein (SP1 on) specifies the switch-on point
and SP1 Aus (SP1 off) the switch-off point of
switch output 1. The values are displayed and set in
the valid unit.
Together, the two parameters determine the switch
function of switch output 1:
If SP1 Aus (SP1 off) is lower than SP1 Ein (SP1
on), the output switches on when the measurement
value exceeds SP1 Ein (SP1 on). It is only
switched off again when measurement value SP1
Aus (SP1 off) falls short (hysteresis function).
If SP1 Ein (SP1 on) and SP1 Aus (SP1 off) are
the same, the output switches when the measure-
ment value exceeds SP1 Ein (SP1 on) and off
when the measurement value falls short of SP1 Aus
(SP1 off).
If SP1 Aus (SP1 off) is larger than SP1 Ein
(SP1 on), the output switches on when SP1 Ein
(SP1 on) < measurement value < SP1 Aus (SP1
off) applies (window function).
Both parameters can be set independently over the
whole measurement range.
SP1 Verzögerung (SP1 delay) allows the reac-
tion of the switch output 1 to be delayed by 0 to
100 s. This value applies the switching on and off in
the same way.
SP1 Funktion (SP1 function) changes the
function of the switch output. Here you can select
whether the contact works as a closer (NO) or
opener (NC).
The change to the switch times takes effect upon
the next switch process. Any previously valid time
continues to run without changes.
With Zuordnung SP (allocation SP) it can be
established which input is allocated to the contacts
for devices with two input channels. It is possible to
allocate both contacts to one channel or each
channel to contact. For the switch point input, the
unit and the entry range are adapted accordingly.
5.4.2 Menu level input
If, during operation, you notice that the measure-
ment value display is very restless, you can stabi-
lize the display (and the output signal) with the pa-
rameters Dämpfung (dampening) and Null-
punktfenster (zero point window).
The effect of the Dämpfung (dampening) parame-
ter corresponds with a capillary reducer. However, it
only affects the display, output signal and switch
point and not the actual measurement cell. You can
set the reaction time to pressure jumps with this pa-
rameter. The value range is 0.0 s to 100.0 s.
At maximum dampening, it takes more than two
minutes until a pressure jump from the
nominal pressure (100%) to zero also
displays zero. The reaction applies cor-
respondingly for other input factors.
In lots of cases, the restless display does not cause
a disturbance in the normal mode but does disturb
in the rest status, therefore when you expect a (dif-
ferential) pressure of zero.
This is the exact purpose served by the Null-
punktfenster (zero point window) parameter.
Its value defines a measurement value range at
around zero. The measurement value is set to 0
within this range. Zero is only no longer output on
the display when the pressure leaves the set win-
dow. From double the window value, the measure-
ment pressure and display then match again. This
avoids jumps in the display.
Setting the offset (zero point shifting) makes sense
if the display shows a different value to zero without
differential pressure (deduct measurement line).
The zero point window should be set to zero by the
offset correction.
Select the Offsetkorrektur (offset correc-
tion) parameter for this and correct the display
value with the buttons þand ÿuntil zero appears
on the display.
5.4.3 Menu level measurement
The output signal of the transmitter primarily de-
pends on the measured pressure. However, you
have the opportunity to adjust the output signal in
other ranges to suit your requirements.

Page 8
The basic measurement range (see
type label) cannot be changed as well
as the type of output signal (voltage or
current).
Both of the channels are configured with three pa-
rameters. Configuration takes place in the same
way as the first one for the second channel.
For channel 1, these are:
Messbereich Anfang
Messbereich Ende
Einheit
For channel 2 correspondingly:
Messbereich 2 Anfang
Messbereich 2 Ende
Einheit 2
The Messbereich Anfang (measurement range
beginning) and Messbereich Ende (measure-
ment range end) initially sets the two pressures
between which the output signal even changes.
Both values can be set over the whole basic meas-
urement range. The set values always relate to the
pressures in the respective valid pressure unit and
are also converted if any changes to the unit are
made.
The signal values (current / voltage) for the Mess-
bereich Anfang (measurement range begin-
ning) and Messbereich Ende (measurement
range end) are fixed in contrast.
If the Messbereich Anfang (measurement range
beginning) is less than Messbereich Ende
(measurement range end), we speak of an in-
creasing curve; the output signal increases with
growing pressure.
If the Messbereich Ende (measurement range
end) is less than Messbereich Anfang (meas-
urement range beginning we speak of a decreas-
ing curve; the output signal drops with growing
pressure.
The difference between the two values Mess-
bereich Anfang (measurement range begin-
ning) and Messbereich Ende (measurement
range end) must be at least 25%of the basic
measurement range.
With the Einheit (unit) parameter, you can se-
lect a unit deviating from the unit of the basic
measurement range. The user must consider that
not each unit makes sense. The calculation is done
automatically.
The Begrenzung (limitation) parameter allows
limitation of the display on the range between the
Messbereich Anfang (measurement range be-
ginning) and Messbereich Ende (measurement
range end)
This makes sense for contents meas-
urements to avoid "negative contents". If
the limitation is set to "no", then the
measurement values that are larger or
smaller than the end of values are shown.
5.4.4 Menu level output
The min. Ausgang (min. output), max. Aus-
gang (max. output) and Fehlersignal (error
signal) parameters specify the limits of the output
signal irrespective of the pressure. These limits
cannot be exceeded or fallen short of. The limit val-
ues have priority over the range specified by the
measurement range beginning and measurement
range end.
These parameters mainly serve the purpose of
suppressing error messages in downstream sys-
tems due to brief measurement range excesses.
The min. Ausgang (min. output) parameter
generally only makes sense for devices with an
output signal 4…20 mA because values under
3.8 mA are frequently assessed as error signals.
The max. Ausgang (max. output) parameter can
be used for voltage and current to limit the maxi-
mum value.
The value specified with the Fehlersignal (er-
ror signal) parameter is issued if the device
identifies an internal error and can no longer work
correctly.
You must make sure that not all possible errors and
defects can be recognized by the actual device.
5.4.5 Menu level function
In the function menu, an adjustment can be made
to the display and the output to suit specific re-
quirements. There are the following functions for
this:
LINEAR: linear implementation of the input on the
display and the output. The range specified in the
"menu level measurement" serves as the meas-
urement range.
RADIZIERT (ROOT EXTRACTED): the input signal is
root extracted here on the display and given to the
output. This is required for the flow measurement
with differential pressure for example. A "free unit"
can be defined for the display. The beginning and
end of the display range and the number of decimal

Page 9
places are specified here. There is also the option
of defining the unit with 4 characters.
TABELLE (TABLE): this function allows the free ad-
aptation of the input to the display and output using
a table with up to 30 bases. The value pairs with
measurement value and display value are entered
for the bases.
Caution: when changing from TABLE to
a different function, the table is initial-
ized again and the existing values are
lost.
With the parameters Nachkomma MB, MB Anfang
and MB Ende (decimal point MR, MR begin-
ning and MR end) the display range is specified.
The user is free to configure.
With Einheit MB (unit MR) the user is given the
opportunity to use a fully independent unit. There
are letters (capital, lower case), numbers and sev-
eral symbols available. The unit can be max.
4 characters.
If the TABELLE (TABLE) function is selected, the
number of pairs must also be entered. With this
parameter, it is specified how may value pairs (ba-
ses) the table consists of. min. 3 and max. 30 bases
are permitted.
Caution: if the number of value pairs is
changed, the table is initialized anew
and the existing values deleted.
With value pair 1 to (maximal) value pair 30,
you can view and change the individual value pairs
A pair of values consists of a measurement value
(left side) and a display value (right side).
The measurement value must be within the meas-
urement range and the display value must be within
the defined "free unit". The respective limits are
displayed upon entry. The table must contain in-
creasing values.
Note:
The function is only effective on channel
1.
5.4.6 Menu level display
The parameters for the display influence are sum-
marized in this menu.
The most important parameter is Farbe (color).
A specific background color (red, green, yellow,
blue, pink, turquoise and white) can be selected
here. However, there are also two automatic func-
tions with color changeover available.
Auto1: red-green,
Auto2: Rd-Ye-Gr.
Alternatively, the background lighting can be per-
manently switched off.
For devices with 2 input channels, an input channel
can be specified which the color change relates to
with the Zuordnung Umschaltung (allocation
changeover). This allocation is independent of the
allocation of switch points.
In the mode with automatic color changeover, there
is the option of entering the necessary switch
thresholds "red-yellow changeover", "yellow-green
changeover", "green-yellow changeover", "yellow-
red changeover, "red-green changeover" and
"green-red" changeover.
The switch thresholds can be shifted within the
measurement range. The sequence of the switch
points cannot be changed.
Note: if a range should not be used, the corre-
sponding switch thresholds can be set to the same
value. An example can be seen in this sketch:
Only the green, yellow and red ranges are required
here. In order to fade out the bottom red and yellow
ranges, the switch thresholds "red-yellow changeo-
ver" and "yellow-green changeover" are set to the
measurement range beginning.
Wertepaar 1
+0.0 Pa +0.0 %
+0.0 ... +100.0 Pa

Page 10
With the Hysterese (hysteresis) parameter, the
quick and unwanted change of color can be pre-
vented. The hysteresis can be set in a range of
0.1... 10%.
Note: for large hysteresis values, attention must be
paid that the ranges of the individual colors do not
overlap. Otherwise it may be the case that the color
change does not work as required.
Another option for avoiding unwanted color chang-
es is offered by the Verzögerung (delay) pa-
rameter. The color change can be delayed in a
range of 0…100s.
If lighting is not required to permanently, the Be-
leuchtungszeit (lighting time) parameter
can be used to set when the lighting switches off af-
ter the last push of a button. Alongside permanent
lighting, automatic shutdown is possible after
10…600 s. The set time is only valid if the Hinter-
grundfarbe (background color) parameter is
not set to "off".
The legibility of the display depends on the temper-
ature and the reading angle among other aspects.
In order to allow the best possible legibility, this can
be adjusted with the Kontrast (contrast) pa-
rameter. When changing the contrast, it can happen
that the display is empty or displayed black. In this
case, the contrast must be enlarged or reduced.
With the Bargraf (bar graph) parameter, the
display can be changed over as follows. The meas-
urement value is either shown with large figures or
the display is made with smaller figures and an ad-
ditional bar graph to be able to detect the meas-
urement value quicker.
5.4.7 Menu level system
The Software Info and Konfig Info menu
points display information on the device. This infor-
mation is helpful to be able to answer questions on
the device more quickly.
In the software info, the device type, controller ID
and die firmware version are displayed.
The configuration information is to be taken from
the basic measurement range, the specified output
signal and the existing contacts.
In the Passwort (password) menu point, the
menu can be protected against unauthorized
changes with a password. The password is a num-
ber from 1 to 999. A 0 entry means that a password
is not active.
A password must be set if the user presses the but-
ton to enter the menu from the normal mode. It im-
mediately jumps back to the normal mode if the in-
correct password is entered. If the password is not
active, the display immediately jumps to the menu.
Caution: the user does not have the op-
tion of deleting a forgotten password!
With the Konfig. laden (load con-
figuration) menu point, a configuration saved by
the user can be loaded. This means you can rein-
state a working set of parameters after adjustment
tests for example.
Note: if a configuration has not yet been
saved by the user, the standard values
(supply status) are loaded. In this case,
any existing measurement range
spreads or switch points are reset and the device
must be reconfigured.
The Konfig. sichern (save configuration)
menu point serves the purpose of saving existing
parameters in a protected memory. This is helpful if
the setting of a working device should be optimized.
You can quickly reinstate the original status with
Konfig. sichern and Konfig. laden.
5.4.8 Menu level statistics
The operating time and the relay switch cycles are
displayed from delivery.
The operating time is displayed in days (d) and
hours (h)

Page 11
6 Maintenance
The device does not require maintenance.
In order to ensure reliable operation and a long ser-
vice life of the device we recommend regular check-
ing of the device as follows:
•Check the function in connection with slave
components.
•Check the tightness of the pressure connection
lines.
•Check the electrical connections.
The exact test cycles have to be adapted to the op-
erating and environmental conditions. The operat-
ing manuals of all other devices are also to be ob-
served if there is an interaction of different device
components.
7 Transport
The product must be protected against severe im-
pacts. Therefore transport is to be effected only in
the packaging intended for transport.
8 Service
All defective or faulty devices are to be sent directly
to our repair department. We would like to ask you
to coordinate all device returns with our sales de-
partment.
Remaining medium in and on disman-
tled measuring instruments may cause
danger to persons, environment and
equipment. Take reasonable precau-
tions! Clean the instrument thoroughly if necessary.
9 Accessories
No accessories
10 Disposal
Protect your environment....
Kindly help us protecting the environ-
ment and dispose of or recycle the
used products in accordance with the
relevant regulations.

Page 12
11 Technical data
Basic measurement range
mbar
4
6
10
16
25
40
60
100
±2.5
±4
±6
±10
±16
±25
±40
±60
±100
Pa
400
600
1000
1600
±250
kPa
0.4
0.6
1
1.6
2.5
4
6
10
±0.25
±0.4
±0.6
±1
±1.6
±2.5
±4
±6
Max. stat. operating pressure
mbar
50
100
250
500
50
100
250
500
Burst pressure
mbar
150
300
750
1500
150
300
750
1500
Characteristic
deviation °)
max
%FS
1.0
1.0
Typ.
%FS
0.5
0.5
TK range°°)
max
%FS/
10K
1.0
0.3
1.0
0.5
0.3
Typ.
%FS/
10K
0.3
0.3
TK zero point°°)
max
%FS/
10K
1.0
0.4
1.0
0.5
0.4
Typ.
%FS/
10K
0.2
0.2
°) : Characteristic curve deviation (non-linear and hysteresis) at 25°C, basic measurement range (linear characteristic curve, not spread)
°°) : in relation to the basic measurement range (not spread), compensation range 0... 60~C
General
Authorized environmental temperature
Authorized medium temperature
Authorized storage temperature
Housing protection class
-10 ... 70°C
-10 ... 70°C
-20 ... 70°C
IP 65 acc. to DIN EN 60529
Electrical data
Nominal voltage
Auth. operating voltage (Ub)
24 VDC / VAC
12-32 VDC / VAC
Electrical connection type
Triple conductor
Output signal
0 … 20 mA
4 ... 20 mA
0 ... 10V
Authorized load
RL(Ub - 4V) / 0.02 A for Ub ≤ 26 VDC/VAC
RL1100 Ω for Ub > 26 VDC/VAC
RL 10 kΩ for Ub 15 VDC/VAC
RL 2 kΩ for Ub 15 VDC/VAC
Characteristic Curve
P1
P2
linear, root extracted, table with 3...30 bases
linear
Programmable switching contacts
2 sets of voltage free relay contacts
as make (no) or break (nc) contact
2 sets of voltage free solid state relay SPST2
as make (no) or break (nc) contact
Umax
Imax
Pmax
32 V AC/DC
2A
64 W/VA
3 ... 32 V AC/DC
0,25 A
8 W/VA (Ron ≤ 4Ω)
Power intake
max. 3 W / VA
Measured Value Display
4-digit LCD with details of the measurement unit
Multi-coloured lighting (red, yellow and green)
Selectable bar graph display
Units
mbar, Pa, kPa, inchWS, mmWS, mmHg
Connections
Electrical connection
2 x M12 round plug connector
Plug 1 for supply and analogue output signals (5-pole, male)
Plug 2 for switch contacts (4-pole, male)
Pressure Connections
Aluminium hose screw connections for hose 6/4mm and 8/6mm
Materials, assembly
Housing material
Material touching medium
Nylon PA 6.6
Silicone, PVC, aluminium, brass
Assembly
Back fixing holes
Wall mounting
2
SPST: Single Pole Single Throw

Page 13
12 Dimensional drawings
Wiring diagram
Programming
With film keypad with menu-guided operation; password lock
Settings
Damping
Display allocation
0.0 ... 100.0 s (jump response time 10/90%)
P1 and P2 are shown at the same time
Switch output
Channel 1 and channel 2
Switch-off point, switch-on point and response time (0...100 s),
Function (opener/closer), allocation to relay
Zero point stabilization
Zero point correction
Zero point window
⅓ of the basic measurement range
⅓ of the basic measurement range
Measurement values around zero are set to zero within these limits
Output signal
characteristic curve
Any settings within the basic measurement range
linear, root extracted, table with 3...30 bases
Password
001 ... 999 (000 no password protection)
Plug 1
Plug 2
Wall mounting plate (optional)
Back view
Without wall mounting plate
(Standard design)
78
90
76
70.5
61.5
75
83
Hose screw connection
M12 plug connection
Drill holes for
plate screws Ø 3.5
Plug 2
n.c.
Signal +Sig 2
Supply -Ub
Signal +Sig 1
Supply +Ub
Plug 1
BN
WH
BU
BK
BN
WH
BU
BK
SP1no
SP2com
SP2no
SP1com

Page 14
13 Order codes
Digital 2-channel differential pressure switch/transmitter with 4 digit color change LCD
DE44
K
W
M
Channel 1 - measurement range
auth. stat. operating pressure
0 …4 mbar............
......50 mbar...............................>
5
2
0 …6 mbar............
......50 mbar...............................>
5
3
0 …10 mbar............
....100 mbar...............................>
5
4
0 …16 mbar............
....100 mbar...............................>
5
5
0 …25 mbar............
....250 mbar...............................>
5
6
0 …40 mbar............
....250 mbar...............................>
5
7
0 …60 mbar............
....500 mbar...............................>
5
8
0 …100 mbar............
....500 mbar...............................>
5
9
0 …160 mbar............
..1500 mbar...............................>
6
0
0 …250 mbar............
..1500 mbar...............................>
8
2
-2.5 …+2.5 mbar............
......50 mbar...............................>
A
6
-4 …+4 mbar............
......50 mbar...............................>
A
7
-6 …+6 mbar............
......50 mbar...............................>
A
8
-10 …+10 mbar............
....100 mbar...............................>
A
9
-16 …+16 mbar............
....250 mbar...............................>
B
1
-25 …+25 mbar............
....250 mbar...............................>
B
2
-40 …+40 mbar............
....500 mbar...............................>
C
5
-60 …+60 mbar............
....500 mbar...............................>
B
3
-100 …+100 mbar............
....500 mbar...............................>
B
4
0 …400 Pa ...............
......50 mbar...............................>
D
7
0 …500 Pa ...............
......50 mbar...............................>
J
7
0 …600 Pa ...............
......50 mbar...............................>
D
8
0 …1000 Pa ...............
....100 mbar...............................>
D
9
0 …1600 Pa ...............
....100 mbar...............................>
E
1
-250 …+250 Pa ...............
......50 mbar...............................>
L
6
0 …1 kPa..............
......50 mbar...............................>
N
1
0 …1.6 kPa..............
....100 mbar...............................>
N
2
0 …2.5 kPa..............
....250 mbar...............................>
N
3
0 …4 kPa..............
....250 mbar...............................>
N
4
0 …6 kPa..............
....500 mbar...............................>
N
5
0 …10 kPa..............
....500 mbar...............................>
E
5
-1 …+1 kPa..............
......50 mbar...............................>
L
8
-1.6 …+1.6 kPa..............
....100 mbar...............................>
L
9
-2.5 …+2.5 kPa..............
....100 mbar...............................>
M
6
-4 …+4 kPa..............
....250 mbar...............................>
M
7
-6 …+6 kPa..............
....100 mbar...............................>
M
8
Channel 2 - measurement range
auth. stat. operating pressure
0 …4 mbar............
......50 mbar.....................................................>
5
2
0 …6 mbar............
......50 mbar.....................................................>
5
3
0 …10 mbar............
....100 mbar.....................................................>
5
4
0 …16 mbar............
....100 mbar.....................................................>
5
5
0 …25 mbar............
....250 mbar.....................................................>
5
6
0 …40 mbar............
....250 mbar.....................................................>
5
7
0 …60 mbar............
....500 mbar.....................................................>
5
8
0 …100 mbar............
....500 mbar.....................................................>
5
9
0 …160 mbar............
..1500 mbar.....................................................>
6
0
0 …250 mbar............
..1500 mbar.....................................................>
8
2
-2.5 …+2.5 mbar............
......50 mbar.....................................................>
A
6
-4 …+4 mbar............
......50 mbar.....................................................>
A
7
-6 …+6 mbar............
....100 mbar.....................................................>
A
8
-10 …+10 mbar............
....100 mbar.....................................................>
A
9
-16 …+16 mbar............
....250 mbar.....................................................>
B
1
-25 …+25 mbar............
....250 mbar.....................................................>
B
2
-40 …+40 mbar............
....500 mbar.....................................................>
C
5
-60 …+60 mbar............
....500 mbar.....................................................>
B
3
-100 …+100 mbar............
....500 mbar.....................................................>
B
4
0 …400 Pa ...............
......50 mbar.....................................................>
D
7
0 …500 Pa ...............
......50 mbar.....................................................>
J
7
0 …600 Pa ...............
......50 mbar.....................................................>
D
8
0 …1000 Pa ...............
....100 mbar.....................................................>
D
9
0 …1600 Pa ...............
....100 mbar.....................................................>
E
1
-250 …+250 Pa ...............
......50 mbar.....................................................>
L
6
0 …1 kPa..............
......50 mbar.....................................................>
N
1
0 …1.6 kPa..............
....100 mbar.....................................................>
N
2
0 …2.5 kPa..............
....250 mbar.....................................................>
N
3
0 …4 kPa..............
....250 mbar.....................................................>
N
4
0 …6 kPa..............
....500 mbar.....................................................>
N
5
0 …10 kPa..............
....500 mbar.....................................................>
E
5
-1 …+1 kPa..............
......50 mbar.....................................................>
L
8
-1.6 …+1.6 kPa..............
....100 mbar.....................................................>
L
9
-2.5 …+2.5 kPa..............
....100 mbar.....................................................>
M
6
-4 …+4 kPa..............
....250 mbar.....................................................>
M
7
-6 …+6 kPa..............
....500 mbar.....................................................>
M
8
Pressure connection
Aluminium screw connection for 6/4 mm hose.......................................................................................>
4
0
Aluminium screw connection for 8/6 mm hose.......................................................................................>
4
1
Electrical output signal (channel 1 and 2)
without analogue electrical output signal ......................................................................................................................>
0
0 - 20 mA 3-conductor channel 1+2.........................................................................................................................>
4
0 - 10 V DC 3-conductor channel 1+2.........................................................................................................................>
5
4 - 20 mA 3-conductor channel 1+2.........................................................................................................................>
6
Operating voltage
24 V DC/AC (12-32 V DC/AC).................................................................................................................................................>
K
Measurement unit
Selectable pressure units..................................................................................................................................................................>
W
Measured value display/switch elements
4-digit color change LCD –2 relay contacts ................................................................................................................................................>
C
4-digit color change LCD –2 semiconductor switches.................................................................................................................................>
D
Electrical connection
M12 plug connection..............................................................................................................................................................................................>
M
Assembly option
Standard (back fixing holes) ..............................................................................................................................................................................................>
0
Wall mounting....................................................................................................................................................................................................................>
W

Page 15
14 Declaration of conformity

Technische Änderungen vorbehalten • Subject to change without notice • Changements techniques sous réserve
Fischer Mess- und Regeltechnik GmbH • Bielefelder Str. 37a • D-32107 Bad Salzuflen • Tel. [phone] • Fax [phone] •
eMail: [email protected] • www.fischermesstechnik.de