FISCHER DS 11 User manual

4.9.08 BA_GB_DS11.fm
Instruction Manual
DS11 Differential Pressure Switch
1. Safety Instructions
1.1. General
This manual contains detailed
information about the product,
and instructions for its installati-
on, operation and maintenance.
Operators and other technical
personnel responsible for the equipment must
read this thoroughly before attempting to install or
operate this equipment. A copy of this manual
must always be kept accessible at the place of
work for reference by concerned personnel.
Chapter 1 (sections 1.2 through 1.7) contains ge-
neral as well as specific safety instructions. Chap-
ters 2 through 10, covering topics ranging from
intended purpose of the equipment to its final dis-
posal, also include important points relating to
safety. Overlooking or ignoring any of these safety
points can endanger humans and animals, and
possibly cause damage to other equipment.
1.2. Personnel Qualification
Personnel responsible for installation, operation,
maintenance and inspection of this product must
have the qualifications, training and experience
necessary to carry out such work on this type of
equipment.
1.3. Risks of Disregarding Safety Instruc-
tions
Disregarding safety instructions, use of this pro-
duct for purposes for which it is not intended, and/
or operation of this product outside the limits spe-
cified for any of its technical parameters, can result
in harm to persons, the environment, or the plant
on which it is installed. Fischer Mess- und Regel-
technik GmbH will not be responsible for conse-
quences in such circumstances.
1.4. Safety Instructions for Operators
Safety instructions for the proper use of this pro-
duct must be followed. This information must be
available at all times to by personnel responsible
for installation, operation, maintenance and in-
spection of this product. Adequate steps must be
taken to prevent the occurrence of hazardous con-
ditions that can be caused by electric energy and
the convertible energy of the process media. Such
conditions can, for example, be the result of impro-
per electrical or process connections. Detailed in-
formation is available in relevant published norms
(DIN EN, UVW in Germany; and equivalents in
other countries), industrial standards
such as DVWG, Ex-, GL-, VDE guide-
lines, as well as regulations of the local
authorities (e.g., EVUs in Germany).
Table of Contents
1. Safety Instructions
2. Intended Applications
3. Product Description and Functions
4. Installation
5. Commissioning
6. Maintenance
7. Transport
8. Service
9. Accessories
10. Disposal
11. Specifications
12. Dimensions
13. Ordering Code
14. CE-Certificate

2
1.5. Modifications Forbidden
Modification or other technical alteration of the product is
not permissible. This also applies to the use of unautho-
rized spare parts for repair / maintenance of the product.
Any modifications to this product, if and as necessary,
should be done only by Fischer Mess- und Regeltechnik
GmbH.
1.6. Operational Restrictions
The operational reliability of the product is guaranteed
only when used for intended purposes. The product must
be selected and configured for use specifically with defi-
ned process media. The limiting values of operating pa-
rameters, as given in the product specification sheet,
must never be crossed.
1.7. Safety Considerations during Installation and
Maintenance
The safety instructions given in this manual, existing na-
tional regulations relating to accident prevention, and the
internal safety rules and procedures of the user organi-
zation regarding safety during installation, operation and
servicing must all be followed meticulously.
It is the responsibility of the users to ensure that only sui-
tably qualified and experienced technical personnel are
used for installation, operation and servicing of this
equipment.
2. Intended Applications
The DS11 is a combination of indicating and switching in-
strument for pressure, differential pressure and partial
vacuum. This series is suitable for various measuring ap-
plications in the field of industrial and sanitary tech-
niques. Typical applications are measurement of
differential pressure between forward- and return flow in
heating systems and monitoring of filters and pumps.
The pressure chamber and the measuring diapragm are
available in different materials to meet various require-
ments.
3. Product Description and Functions
3.1. Schematic Diagram
3.2. Principles of Operation
The monitoring and switching instrument is based on a
rugged and uncomplicated diaphragm movement suita-
ble for overpressure- partial vacuum- and differential
pressure measurements. The operating principle of the
system is identical in all three applications.
In a state of equilibrium, the forces of the springs on both
sides of the diaphragm are balanced. The pressure or
differential pressure to be measured creates an unbalan-
ced force at the diaphragm. This force moves the dia-
phragm system against the force of the springs for the
measuring range until a new equilibrium is reached.
When the subjected to excessive pressure, the dia-
phragm rests on metal sup-porting plates.
A centre-mounted tapped transfers the motion of the dia-
phragm sys-tem to the indicator movement ant to the in-
itiating elements of the microswitches.
4. Installation
The instrument is intended for wallmounting. It can be at-
tached directly to flat walls by three mounting feet cast to
the casing. The instrument can be mounted into switch-
board by panel mounting kit DZ11. It is factory-callibrated
in vertical position and may not be mounted otherwise.
To ensure proper operation during installation and
maintenance, appropriate shut-off fittings have to be in-
stalled at the plant. By using recommended accessories
(see 9. Accessories, 13. Dimensions and data sheet
measuring device accessories MZ) the instrument can
be
• depressurized or taken out of operation
• cut off from the relevant pipe net for repair or mainte-
nance purposes
• checked and controlled directly on the spot.
4.1. Process Connections
• Only qualified technicians authorized for this type of
work should undertake installation.
• Only for intended mechanical process connection
(see ordering code on instrument’s type plate)
• Ensure that process equipment and pressure lines
are at atmospheric pressure before making pressure
connections.
• The instrument should be provided with suitable pro-
tection against pressure surges (e.g., snubber or pul-
sation damper).
• Ensure that the mechanical configuration and materi-
als of construction of the instrument are compatible
with the process media.
• Ensure that process pressure is always less than the
specified safe pressure rating.
1. Pressure chamber
2. Motion work
3. Tappet
4. Initiating elements for
microswitches
5. Measuring springs
6. Measuring diaphragm

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4.2. Electrical Connections
• Only qualified technicians authorized for this type of
work should undertake installation.
• Electrical connections must comply with relevant in-
ternational, national and local regulations and norms
relating to electrical and instrumentation installations.
• Switch off electrical power to the plant before attemp-
ting electrical installation work of any kind.
• Make electrical connections to the instrument through
a suitable fuse.
5. Commissioning
• Power supply and signal cabling to the instrument
must be correctly selected to meet operational requi-
rements, and installed in a way that does not cause
physical stress to the instrument.
• Pressure lines must have a downward gradient throu-
ghout, from the pressure instrument to the process
vessel / pipe. This is to prevent formation of air / gas
pockets (for liquid applications) and liquid plugs (for
air / gas applications). If this continuous downward
gradient cannot be provided for any reason, then sui-
table water and / or air separation devices must be in-
serted in the pressure line.
• The pressure lines must be kept as short as possible
and must not have short bends to avoid measurement
errors induced by pressure line delays.
• When used with liquid media the lines must be vented
to avoid measurement errors induced by different
heights in liquid columns.
• The instrument and lines must be protected against
frost when used with water.
• Check all pressure connections for leaks before com-
missioning.
5.1. Pressure Connections
The instruments pressure ports are marked by “+“ and
“−“ symbols. The pressure applications need to be instal-
led according to the label.
Differential pressure measurement:+higher pressure
−lower pressure
Pressure measurement: +pressure port
Negative pressure measurement: −negative pressure
port
5.2. Pulsation Damping
During pulsating pressure on the plant mechanical wear
and disturbances in functional capability may occur. To
avoid this we recommend installing absorbers into the
pressure lines.
For Liquid Media
For Gaseous Media
Capilliary reactive coil MZ401
5.3. Zero Point Adjustment and Setting of Swit-
ching Points
5.3.1. Zero Point Adjustment
• Vent pressure lines to atmosphere.
• Remove cover.
• Set measuring indicator to zero by zero point adjust-
ment screw (see 5.3.).
• Mount cover.
5.3.2. Setting of Switching Points
• Unscrew plugs from cover.
• Set desired switching points according to marks on
Adjustable attenuator
valve MZ41
During operating conditi-
on adjust needle valve
that way, that the indica-
tor follows changements
of pressure delayed.
G¼
needle valve be-
hind sealing cap
Zero point adjustment screw
Switching point adjustment

4
reference value scale by screwdriver. Achievable ac-
curacy: 5% FS. More exact settings can be achieved
by using accessories like testing manometer, ohm-
meter on site or ex factory.
• Screw plugs in.
5.4. Connection Scheme
6. Maintenance
The instrument is inherently maintenance-free.
However, to ensure reliable operation and maximize the
operating life of the instrument, it is recommended that
the instrument, its external electrical and process con-
nections, and external connected devices be regularly in-
spected, e.g.:
• Check the display.
• Check the switching output connections and external
devices that are connected to these.
• Check all pressure connections for leak-tightness.
• Check the integrity of all electrical connections of the
instruments.
Inspection and test schedules depend on operating and
site conditions. The operating manuals of other equip-
ment to which the transmitter is connected must be read
thoroughly to ensure that all of them work correctly when
connected together.
7. Transport
The product must be protected against shock and vibra-
tion during transport. It must therefore be properly pack-
ed, preferably in the original factory packaging,
whenever it is to be transported.
8. Service
Any defective devices or devices with missing parts
should be retourned to Fischer Mess- und Regeltechnik
GmbH. For quick service contact our service department.
9. Accessories
9.1. DZ11
Panel mounting kit ø132 mm consisting of front ring, spa-
cer and fastening screws.
9.2. DZ13/14
Three- and four-spindle shut-off and equalizing valves
DZ13/14 are especially suited for mounting differential
pressure instruments. For example they are used for:
• Depressurizing or shutting down of plant.
• Cutting differential pressure instruments off a plant to
enable controlling or repairing.
Shut-off valves may be used for operational checks on si-
te. DZ14 - additional to DZ13 - is provided with a venting
valve to ventilate the connected pipe system. Nominal
pressure of these shut-off and equalizing valves is PN40.
Case is available in aluminium, brass or stainless steel
1.4301. Several process connections acc. to Ordering
Code are available.
10. Disposal
Protect your environment!
Use the product in accordance with re-
levant regulations. Please be aware of
environmental consequences of dispo-
sal at the end of the product's life, and
take care accordingly.
Gerät druck- und spannungslos
6413 2
S1 S2
5
Instrument pressureless and dead

5
11. Specifications
General
Measuring range 0... 400 mbar up to 0... 25 bar (see ordering code)
Nominal pressure 25 bar
Max. static operating pressure Acc. to measuring range (see ordering code)
Max. pressure load One-sided overpressure protected up to nominal pressure
on (+) - and (−) side of diaphragm, partial vacuum protected
Perm. ambient temperature -10... +70°C (but max. 55°C in case of SEV)
Perm. medium temperature 70°C
Protection class IP 54 acc. to DIN EN 60529
Mounting position Vertical
Measuring accuracy ± 2.5% FS
Zero adjustment Located in the dial
Switching Elements
Contact output 1 or 2 microswitches, 1-channel change-over contacts
Adjustment of switching points External adjustment by standard value scales
smallest adjustable value: approx. 5% FS
Switching hysteresis Approx. 2.5% FS
Load data / contacts U~max. = 250 V AC, Imax. = 5 A, Pmax. = 250 VA
U=max. = 30 V DC, Imax. = 0.4 A, Pmax. = 10 W
Electrical Connection Numbered cable, prewired terminal box, 7-channel plug
Pressure Connection Thread G1/4 female, cutting ring connection for 6, 8, 10,12 mm ∅tube
of brass, zinced steel or chrome nickel steel
connection shank G1/4 male DIN EN 837
Measuring System
Measuring ranges s16 bar Diaphragm measuring system, diaphragm of fabric back stayed elastomer
Measuring range 0-25 bar Diaphragm measuring system, diaphragm of DURATHERM®
Materials
Pressure chamber Aluminium GkAlSi10(Mg), varnished black
Aluminium GkAlSi10(Mg) HART-COAT®
Chrome nickel steel 1.4305
Measuring diaphragm Diaphragm measuring system and gaskets of NBR or Viton®
Diaphragm of DURATHERM®NiCrCo-alloy
Materials: medium Stainless steel 1.4310, 1.4305
Materials: housing Macrolon
Weight Pressure chamber of Aluminium = 1.2 kg, pressure chamber of 1.4305 = 3.5 kg
Approval Approval acc. to SEV guidelines for low voltage products
Type approval acc. to German Lloyd, test mark
Mounting Wallmounting - 3 fastening elements
Panel mounting - panel mounting kit DZ11 ø132 mm
Pipe mounting, pressure connections V(+), (−) symbols
- by screwed-in cutting ring or clamping ring connection
- by screwed-in connection shank acc. to DIN EN 837 for nipple fitting acc. to
DIN 16288

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12. Dimensions (all units in mm unless stated otherwise)
DS11 Wall mounting
(standard version)
M16x1.5 plastic
cable gland
Cutting ring
connection
M20x1.5 screwed cable gland Connections
G¼ female
Connection
shank G ¼ acc.
to DIN EN 837
Variants of electrical connection Variants of process connection
Panel mounting
DZ13/14 Four-spindle shut off and equalizing valves
open 90
open 78
Measuring
instrument
Ventilations
Schematic diagram
DZ13/14
Ventilation
(only DZ14)
Cutting ring connection
Panel cutout Ø 104
Cable terminal box
or 7-channel plug

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13. Ordering Code
Differential Pressure Switch DS11
Measuring Range Max. Static Operating Pressure
0 . . . 400 mbar 6 bar............................................... > 8 3
0 . . . 0.6 bar 10 bar............................................... > 0 1
0 . . . 1 bar 16 bar............................................... > 0 2
0 . . . 1.6 bar 25 bar............................................... > 0 3
0 . . . 2.5 bar 25 bar............................................... > 0 4
0 . . . 4 bar 25 bar............................................... > 0 5
0 . . . 6 bar 25 bar............................................... > 0 6
0 . . . 10 bar 25 bar............................................... > 0 7
0 . . . 16 bar 25 bar............................................... > 0 8
0 . . . 25 bar 25 bar............................................... > 0 9
-0.6. . . 0 bar 10 bar............................................... > 3 0
-1. . . 0 bar 16 bar............................................... > 3 1
-1. . . 0.6 bar 25 bar............................................... > 3 2
-1. . . 1.5 bar 25 bar............................................... > 3 3
-1. . . 3 bar 25 bar............................................... > 3 4
-1. . . 5 bar 25 bar............................................... > 3 5
Measuring Diaphragm /Gaskets
NBR NBR (all ranges up to 16 bar).......................... > N
Viton®Viton® (all ranges up to 16 bar)........................ > V
DURATHERM®NBR (measuring range 0-25 bar only)............. > D
DURATHERM®Viton®(measuring range 0-25 bar only) .......... > E
Pressure Chamber
Aluminium................................................................................................. > A
Aluminium HART-COAT®........................................................................ > D
Chrome nickel steel 1.4305 ...................................................................... > W
Pressure Connections
Female thread G1/4.......................................................................................... > 0 1
Connection shank G1/4 B male of brass .......................................................... > 0 6
Connection shank G1/4 B male of stainless steel ............................................ > 1 1
Cutting ring connection for 6 mm tube of steel ............................................... > 2 0
Cutting ring connection for 8 mm tube of steel ............................................... > 2 1
Cutting ring connection for 10 mm tube of steel ............................................... > 2 2
Cutting ring connection for 6 mm tube of stainless steel 1.4571 ...................> 2 4
Cutting ring connection for 8 mm tube of stainless steel 1.4571 ...................> 2 5
Cutting ring connection for 10 mm tube of stainless steel 1.4571 ................... > 2 6
Cutting ring connection for 6 mm tube of brass............................................. > 2 8
Cutting ring connection for 8 mm tube of brass............................................. > 2 9
Cutting ring connection for 10 mm tube of brass............................................. > 3 0
Switches
1 adjustable microswitch...................................................................................................> A
2 adjustable microswitches...............................................................................................> B
Electrical Connection
Numbered cable, 1 m long, prewired.....................................................................................> 1
Numbered cable, 2.5 m long, prewired.....................................................................................> 2
Numbered cable, 5 m long, prewired.....................................................................................> 5
Cable terminal box....................................................................................................................> K
7-channel plug ..........................................................................................................................> W
German Lloyd approval , 3 m numbered cable H07 RNF.........................................................> Z
SEV-approval, 2 m numbered cable VDE NYSLYO .................................................................> U

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
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14. CE-Certificate