s
Operating Instructions Edition 06/2005
SIWAREX R
RN Series of Mounting Units
s
SIWAREX R
Mounting units for RN series load cells
Operating Instructions Chapter overview
Safety Notes...................................................................................................... 4
General Information.........................................................................................5
1. General Setup and Installation Requirements................................6
1.1 Lift off protection..................................................................................6
1.2 Overload protection.............................................................................6
1.3 Guide elements ...................................................................................7
1.4 Load cell dummies...............................................................................8
1.5 Load cell handling................................................................................8
1.6 Welding and fitting...............................................................................9
1.7 Fitting...................................................................................................9
1.8 Bearing surfaces................................................................................10
1.9 Special features of bending ring load cells ........................................11
1.10 De-installation....................................................................................11
2 Elastomer Bearing........................................................................... 12
2.1 Technical description......................................................................... 12
2.1.1 Area of Application ............................................................................ 12
2.1.2 Construction ......................................................................................12
2.2 Fitting................................................................................................. 13
2.3 Technical data...................................................................................14
2.3.1 Functional data.................................................................................. 14
2.3.2 Dimensions........................................................................................14
2.4 Care and maintenance ......................................................................15
2.5 Ordering information..........................................................................16
3 Self-aligning Bearing....................................................................... 17
3.1 Technical description......................................................................... 17
3.1.1 Area of Application ............................................................................ 17
Document No.: A5E00239116 Page 2
3.1.2 Construction ......................................................................................17
3.2 Fitting................................................................................................. 18
3.3 Technical data...................................................................................21
3.3.1 Functional data.................................................................................. 21
3.3.2 Dimensions........................................................................................21
3.4 Care and maintenance ......................................................................21
3.5 Ordering information..........................................................................22
4 Combination Mounting Unit............................................................23
4.1 Technical description......................................................................... 23
4.1.1 Area of Application ............................................................................ 23
4.1.2 Construction ......................................................................................23
4.2 Fitting................................................................................................. 24
4.3 Technical data...................................................................................26
4.3.1 Functional data.................................................................................. 26
4.3.2 Dimensions........................................................................................27
4.4 Care and maintenance ......................................................................27
4.5 Ordering information..........................................................................27
5 Guide Element for Combination Mounting Unit............................ 28
5.1 Technical description......................................................................... 28
5.1.1 Area of Application ............................................................................ 28
5.1.2 Construction ......................................................................................29
5.2 Fitting................................................................................................. 30
5.3 Technical data...................................................................................31
5.3.1 Functional data.................................................................................. 31
5.3.2 Dimensions........................................................................................31
5.4 Care and maintenance ......................................................................32
5.5 Ordering information..........................................................................32
6 Grounding Cable ............................................................................. 33
6.1 Technical description......................................................................... 33
6.1.1 Area of Application ............................................................................ 33
6.1.2 Construction ......................................................................................33
6.2 Fitting................................................................................................. 33
6.3 Dimensions........................................................................................34
6.4 Care and maintenance ......................................................................34
6.5 Ordering information..........................................................................34
Document No.: A5E00239116 Page 3
Safety Notes
DANGER
indicates that death, severe personal injury or substantial property damage will
result if proper precautions are not taken.
WARNING
indicates that death, severe personal injury or substantial property damage can
result if proper precautions are not taken.
CAUTION
together with the triangle indicates that minor person al injury can occur if proper
precautions are not taken.
CAUTION
without the triangle means that material damage can occur if proper precaution s
are not taken.
ATTENTION
indicates that an undesirable result or condition can occur if the corresponding
note is not observed.
NOTE
indicates a referral to a potential benefit if the recom mendation is followed.
Qualified personnel in the sense of the safety notes in this ope ration manual and
on the product itself are persons familiar with setting up. Installing, commissioning
and operation of this product. They must possess the authorization and the
qualifications to install, commission an d maintain devi ce s, system s and circuitry in
accordance with international regulatio ns for safety.
Copyright © Siemens AG 2005 All rights reserved
The reproduction, transmission or use of this document or its
contents is not permitted without express written authority.
Offenders will be liable for damages. All rights, including rights
created by patent grant or registration of a utility model or design,
are reserved.
Siemens AG
Automation & Drives Division
Process Instrumen t ation and nalytics Department A
D-76181 Karlsruhe, Germany
Exclusion of liability
We have checked the contents of this manual for agreement with
the hardware and software described. Since deviations cannot be
precluded entirely, we cannot guarantee full agreement. However,
the data in this manual are reviewed regularly and any necessary
corrections included in subsequent editions. Suggestions for
improvement are welcomed.
© Siemens AG 2005
Technical data subject to change.
Document No.: A5E00239116 Page 4
General Information
Use for the intended purpose
Use for the intended purpose means that this product may only be used within the
limits of the technical specifications and statement of purpose of this operating
manual.
This device will not be a source of danger provided it is used for the intended pur-
pose under consideration of the safety instructions.
Perfect, safe operation of this device is conditional upon proper transport, storage,
installation and assembly.
Proper operation of this de vice can only be ensured if the specifications provided in
technical data are observed.
Improper handling can result in death, severe pe rsonal injury and property dam-
age.
Notes on product liability
We expressly point out that the nature of the product is describe d exclusively and
conclusively in the contract of sale. The conte nts of this product documentation are
not part of an earlier or existing agreement, acceptance or legal relationship nor do
they affect these in any way. The particular contract of sale determines the sum of
obligations to be met by Siemens and the guarantee regulation co ntainer therein is
complete and is the sole regulation that shall apply. This contractual guarantee
regulation is neither extended nor limited by the information provided in this docu-
ment.
Information on delivery
The scope of delivery in accordance with the valid contract of sale is listed in the shipping
documents enclosed in the delivery.
Please observe any relevant instructions when opening the packaging. Check the
shipment for completeness and possible transportation damage. In particular,
compare the order number on the rating plate with the order information.
Please read this operating manual b efore starting work! It contains important in-
formation and data that, if observed, ensure the overall safety and functionality of
this device. Following these instructions will make it easier for you to use handle
this product and ensure reliable mea su ring results.
Document No.: A5E00239116 Page 5
1. General Setup and Installation Requirements
1.1 Lift off protection
Lift off protections prevent lifting off of the upper plates of the load cells or ove r-
loading of fixed installation load cells by pulling in the opposite direction to the
measurement direction. Lift off protections are necessary if there is a dang er of the
load carrier being lifted or tilted. This can occur, for example, when containers are
tall and light or in free-standing silos (wind load).
The lift off protections are incorporate d
into the combined mounting units in the
RN series. It may be necessary to con-
struct lift off protections if other types of
mounting units are used. A proposal for
a lift off protection solution is shown in
Fig. 1-1. The distance X marks the pos-
sible lift travel of the load carrier. The
hole diameter ØD must be considerably
greater than the bolt diameter Ød. Load
carrier movement must not be impeded. Fig. 1-1 Proposed solution
for lift off protection
1.2 Overload protection
Under overload protection is meant the protection of load cells against an exces-
sive load in the direction of measurement. However, lateral forces can also occur
that exceed the load cell load limits.
Overload protection in measurement direction
Load cells are normally protected against vertical overload by having a travel limit
stop bolt placed underneath the thrust piston. This limits the load cell measurement
travel. The SIWAREX RN series ring load cells have a very small measurement
travel of 0.07 to 0.2 mm. Adjustable travel limit stops are not easy to deal with in
practice. For this reason, the RN seri es load cells up to a nominal load of 13 t have
an overload protector integrated. For load cells with high nominal loads, the danger
of accidental overload is not so great. Any additional loads can be taken into ac-
count in the dimensioning of the load cell.
Another way of protecting load cells against overload is to over-dimension them.
Overload protection in lateral direction
Lateral forces are caused by, for example, wind, filling operatio ns, acceleration or
conveyor belt friction. If these forces exceed certain values, the load cell must be
protected against them.
In the RN cells, weight is directed to the load cell via pendulum bolts or elastomer
bearings. These elements allow a certain degree of sideways travel of the load car-
rier or a change in its length due to heati ng. They generate, depending on the de-
gree of travel, a reciprocal force that tends to re-centralize the load carrier. This
travel is both desirable and necessary for accurate weighing. If the lateral force is
high enough to exceed the reciprocal force of the pendulum bolt o r elastomer
bearing up to the limit of travel, appropriat e safety measures must b e taken. These
may be in the form of swing limiters or guide elements (see Chapter 1.3).
Document No.: A5E00239116 Page 6
Edition 06/05 General Construction and Installation Requirem ents
Swing limiters must be constructed or adjust ed such that the allowable degree o f
swing in all axes cannot be exceeded. This is shown in two examples in Fig. 1-2.
±2.8
±4
2.8
±4
±4
4
Limit stop
Drill hole
Bolt
PlatformPlatform
±2.8
±4
2.8
±2.8
±4
2.8
±4
±4
4
Limit stop
Drill hole
Bolt
PlatformPlatform
Two examples of weigh platform swi ng limiting with an allowable travel
of 4 mm.
Fig. 1-2 Example of swing limiting
Swing limiters are integrated into the combined moun ting units in the RN series.
CAUTION
When using load cells with small nominal loads, overload protectors should be
used, also laterally, to prevent damag e to the load cells.
Using load cells above their maximum operating or lateral load rating can result in
irreparable damage, including shea ring of the load cell or the fitted unit.
1.3 Guide elements
Guide elements directly take up lateral forces. Th ey do not allow any sideways
movement of the load carrier. At the same time they must not cause strain when
the anchorage points move relative to each other (caused, for example, by thermal
expansion). How guide elements a re id eally located in shown in Figs. 5-1, Page 28
and 5-2, Page 29. They are often used when a weight must be determined in the
presence of a lateral force.
Swing anchors must be fitted exactly vertical to the operating direction of the load
cell, such that no force compone nts are created in the weighing direction. Strain on
the anchors can be most easily avoided by when these are fitted with the same di-
rection of rotation. Three guide elements are sufficient to restrain a weig hing plat-
form or container. Use of four anchors can bring the great dang er of tensioning
these relative to one another and thereby inducing a measurement error. If, how-
ever, four guide elements must be used, these must be fitted with enough play.
The guide elements used must follow e stabli shed weighing technology prin ciples.
For the SIWAREX R RN series of combi nation mounting units, ball joint guide ele-
ments up to 1.7 kN are available for the weight class 500 kg to 13 t. Upon request,
ball pin guide elements can be delivere d up to 1000 kN lateral force.
Document No.: A5E00239116 Page 7
Edition 06/05 General Construction and Installation Requirem ents
1.4 Load cell dummies
Load cells are sensitive sensors. To protect them from damage during transport
and installation, they should be fitted as late as possible. During transport and in-
stallation they should be therefo re replaced by temporary units, so-called dummies
or phantoms. Dummies can, for example, be made up as follows:
1. Simulating the load cell body with a metal part.
In the simplest case, a piece of piping with the same external diameter as
the load cell to be replaced is fitted in a self-aligning bearing or combina-
tion fitted unit. The length of the pipe corresponds to the unloaded distance
between the upper plate and the base plate. The disadvantage is that there
is no fixed connection betwee n the upp er plate and the base plate.
2. Simulating the component with a welded construction.
A steel pipe or other steel profile is welded between the two plates with the
holes for the mounting bolts. The total height is the same as that of the
component. This is the safest and mo st stable solution. Heavy fitting work
can be carried out.
3. Use a SIWAREX R combination mounting unit.
The combination mounting units are deliv ered already assembled. The
units are set to the approximate height of the unit in operational condition.
Light fitting work can be carried out.
1.5 Load cell handling
DANGER
Load cells and mounting u nits are not machine parts that are constructed with
usual safety factors. It is therefore absolutely necessary to provide crash or
catastrophe protection in line with the potential for da nger.
CAUTION
To protect against unwanted electrical currents, such as tho se produced by weld-
ing or lightning, the load cells must be bridged with highly flexible grounding cable
(e.g. SIWAREX R grounding cable 7MH3 701-1AA1).
SIWAREX R load cells may only be installed and con nected up by qualified
personnel.
Load cells are precision units and must be handled d elicately. This must be
particularly taken into account when tran sporting and fitting.
Document No.: A5E00239116 Page 8
Edition 06/05 General Construction and Installation Requirem ents
CAUTION
Mechanical shock or dropping can damage the load cell irreparably.
Load cells may not be carried by their connecting cables.
The load path must be exactly in the direction of measurement of the load cell.
Torsional and bending torques, off-cente r loadin g and lateral loading introduce er-
rors that on one hand give false measurement re sults and on the other cam dam-
age the load cell or fitted element if the permissible limits are exceeded.
Mounting units in general allow enough play such that thermal expansion do es not
lead to lateral loading.
1.6 Welding and fitting
As long as all fitting work on scales construction h as not been concluded, the load
cells should be replaced by dummies to protect them from shock or welding cur-
rents.
CAUTION
If welding is necessary after fitting the load cells, ca re must be taken that under no
conditions does welding current pass through the cells. The grounding cable of the
welder must be firmly attached to a point near the welding lo cation. The load cells
must be bridged across with an gro unding cable. Each load cell mu st be discon-
nected.
1.7 Fitting
Load cells must never be overloaded. The load carrier must be set down slowly on
top. There is a danger, particularly for load cell s with low nominal loads, that at-
taching thrust pistons can bend the load cell body, e.g. by the tightening of lock-
nuts.
WARNING
Suitable lifting tackle is to be used to raise the load carrier. The a ppropriate safety
precautions must be take n.
NOTE
The load carrier sh ould have a cast-in plate or eyelet bolts to permit safe use of
lifting tackle.
If overload protectors are present, these must be set up to safely handle the de-
sired load. They must be capable of allowing a n increase in weight up to the nomi-
nal value.
Overload protectors are to be protected against dirt and icin g up.
Document No.: A5E00239116 Page 9
Edition 06/05 General Construction and Installation Requirem ents
Overload protectors must be checked for trouble-free operation in the course of
regular maintenance.
DANGER
Dirty, iced up or wrongly adjusted overload protectors lead to incorrect meas-
urement due to blockage or an overflow of the scal es, with possible ensuing
material damage or bodily injury.
CAUTION
Correct fitting of load cells and fitted elements is to be chec ked, for example by
inspecting the fitting tolerances and swing travel. Fau l ty construction can lead to
destruction of the load cell and the fitted element.
Care should be taken that the cable is not damaged or cut.
The cable is to be laid in the cabl e clamps in a vertical, downwards-hanging loop
to discourage the ingress of water.
1.8 Bearing surfaces
The mating surfaces of the mounting units must fulfill the following requirements:
• Positional and angular displacements of the installation surfaces relative to
each other shall conform to the general tolerances for welded structures
EN ISO 13920.
• The foundations must be absol utely firm and free from subsidence. Flat
steel plates, on which the fitted elements are mounted, must be ca st into
concrete foundations.
• The mounting surface must be vertical to the direction of measurement and
should preferably be on one level.
With more than three mounting points, the load distri bution is mostly statically in-
determinate. With firm foundations and stiff load carriers, the loa d is of necessity
not equally distributed across all load cells. Two diagonally opposed load cells
carry the main load. The other cells only support the load carrier. This is also the
case if subsidence of the foundations is to be catered for. There are two ways of
taking this into account:
1. Over-dimensioning the load cells
The load cell nominal load is calculated such that, with four mounting points, the
total weight can be carried by two load cells.
2. Mounting points height compensation
In this method, the output signals of all load cells are tuned to each other under
load. To give each a similar load, spacers are used to equalize the height.
The spacers are best pushed between the mounting plate and the upper plate.
The output signals from each load cell correspond to the load distribution.
To measure the output signal, proceed as follo ws:
Disconnect load cell wires SIG+ and SIG-.
• Provide load cell with power (e.g. 10.2V).
• Measure output voltage of all load cells across SIG+ and SIG-.
Document No.: A5E00239116 Page 10
Edition 06/05 General Construction and Installation Requirem ents
• The mounting plate of the load cell with the lowest value should b e built up
with spacers until the output voltages are equalized.
The load cell seating must be vertical, completely flat and, as the load cell foot, ab-
solutely clean.
The thrust piston mating surfaces must be coate d with high performance grease.
1.9 Special features of bending ring load cells
Bending ring load cells have a very small measurement travel. In addition, load
cells with a nominal load of up to 13 t have an integrated overload protection. This
causes the mounting surfaces to limit the travel of the thrust piston tube. The load
cell mounting surface should be carefully checked for contamination before fitting.
If there is a danger of the installed load cell becoming contaminated or ice d up in
operation, appropriate check and/or sealing is necessary. The underside can, for
example, be protected by a greased se al or a non-hardening sealing compound. It
should be remembered when taki ng such measures that the thrust pistons on the
upper side of the load cell should also be well sealed to effectively prevent the in-
gress of moisture.
1.10 De-installation
The same security precautions and requirements apply to de-installation as for in-
stallation and fitting.
• Switch off all main or auxiliary power.
• Secure the load carrier against falling.
• Use suitable lifting equipment and tackle.
• Release pressure on the load cell a nd remove carefully without using force.
• Do not cut the cabling if the load cell is to be reused or sent for rep air.
• Do not carry or pull the load cell by its cabling.
Document No.: A5E00239116 Page 11
2 Elastomer Bearing
2.1 Technical description
2.1.1 Area of Application
The elastomer bearing prot ects the load cell when shock-type loads or vibrations may oc-
cur.
These self-center the load carrier. Together with the self-aligning bearing bottom part,
they offer a simple method of load cell mounting.
2.1.2 Construction
A complete elastomer beari ng unit consists of the order items self-aligning bearing bottom
part, load cell and elastomer bearing.
The self-aligning bearing bottom part (1) is bolted to the foundation with four bolts. The
load cell (3) is fixed between three spring pins (2). A pressure piece (4) is set in the load
cell (3). The elastomer bearing (7) sits with a pendulum bolt (5) as thrust piston in the
load cell (3) and is bolted to the load carrier. The elastomer bearing (7) an d thus the load
carrier is centered via the pendulum bolts (5). Lateral movement of the load carrier is
possible to a certain degree. A flat seal (6) between load cell (3) and elastomer bearing
(7) protects the thrust piston from contamination.
The elastomer bearing is a bonded rubber joint made from neoprene and stainless steel.
Nominal load A
0.5, 1 t 97
2, 3.5, 5 t 102
10, 13 t 120
No. Nomenclature
1 Self-aligning bearing bottom part
2 Spring pin
3 Load cell
4 Pressure piece, load cell
5 Pendulum bolts
6 Flat seal
7 Elastomer bearing
Fig. 2-1 Elastomer bearing construction
RN 60 to 280 kg RN 0.5 to 13 t
Document No.: A5E00239116 Page 12
Edition 06/05 Elastomer Bearing
2.2 Fitting
Fitting situations can differ considerably. The load carrier dead weight can vary f rom a
few kilograms up to many tons. It may be, for example, a container, a platform or a rolling
road. The following fitting instructions can therefore only be of a general natu re .
WARNING
Suitable lifting tackle is to be used to raise the load carrier. The a ppropriate safety
precautions must be take n.
The load carrier should always be built on dummies to prevent the load cells being dam-
aged during installation. The load carrie r only then needs to be lifted a few millimeters
mounting plate by mounting plate to place the elastomer be arings.
Fitting procedure: (For nu mbering see Fig. 2-1)
1. Prepare load cells:
• A data sheet with calibration values is delivered with ev ery load cell. It can be
found in a transport pouch glued to the p ackaging. Remove the data sheet and
store it securely.
• Unpack the load cell.
• A pressure piece (4) is set in the load cell (3) and secured against falling out with
adhesive tape. Pull off the adhesive tape and check t hat the pressure piece is
seated correctly.
2. Prepare self-aligning bearing bottom part:
• Unpack the self-aligning bearing bottom part (1).
3. Prepare elastomer bearing:
• Unpack the elastomer bearing (7).
• Check that the flat seal (6) is seated correctly.
• Apply bearing grease to pendulum b olt ball-head (5).
4. Assembling elastomer bearing unit:
• Place the load cell (3) betwee n the spring pins (2) in the base plat e.
NOTE
When dealing with load cells, please note Chapter 1.5 - handling of load cells.
• Place elastomer bearing (7) in the load cell (3).
• To check for correct fitting and parts, me asure the total height of the bush unit
and comparing with fitting dimensions, Fig. 2-1, Page 12.
CAUTION
Wrong or incomplete fitting can result in damage to load cells, installable
components and load carrier.
DANGER
A falling load carrier can, depending on t he degree of potential danger, cause
severe bodily injury or considerable material damage.
Document No.: A5E00239116 Page 13
Edition 06/05 Elastomer Bearing
5. Installing elastomer bearing unit:
• Release bolts holding dummies.
• Raise load carrier at first mounting plate and remove dummy.
• Insert elastomer bearing unit and screw in holding bolts loosely.
• Slowly let down load carrier.
• Install remaining elastomer bearing units as described.
• Check that elastomer beari ngs are not under tension.
• Tighten up holding bolts.
2.3 Technical data
2.3.1 Functional data
Nominal load 60 kg – 5t 10 t – 13 t
Allowable lateral travel ± 4 mm ± 6 mm
2.3.2 Dimensions
Fig. 2-2 RN 60 to 280kg dimensions
Document No.: A5E00239116 Page 14
Edition 06/05 Elastomer Bearing
Nennlast A B C ØD E F G H K ØL M N
0,5, 1 t 100 75 97 85 25 15 6 100 75 11 11 9,5
2, 3,5, 5 t 120 90 102 100 30 15 6 100 75 11 11 8,5
10,13 t 120 90 120 100 35 20 6 120 90 11 14 20
Fi
g
. 2-3 0.5 to 13 t RN dimensions
2.4 Care and maintenance
General
Unfavorable storage conditions or incorrect handling change the physical properties of
many rubber product s. The y can be rendered unusable through becoming too hard or too
soft, becoming permanently deformed, flaking or cracking or other surface damage.
These changes can be caused by the effects of, for example, ozone, heat, light, damp,
solvents or storing under tension.
Correctly stored and handled rubbe r products remain unchanged in their physical proper-
ties over a long period (several years).
Lifetime and checks
The lifetime of elastomer parts depends on their construction and loading.
Rubber is subject to a natural aging process.
For loads at acceptable levels, a service life of over 6 years can be expected.
The bonded rubber parts are maintenance-free in operation. The pendulum bolt ball-head
must be greased as necessary.
A visual inspection of the parts should be made 6 months after fitting and once per year
thereafter. Testing the rubber-metal bond can be done by a mechanical manual check.
The rubber can be pressed back wi th a blunt “testing iron” (pressing side with a radius).
If partial edge loosening in the bonded area between the elastomer and the metal or sur-
face cracks occur in the individual elastomer layers, these locations must be rechecked at
regular intervals.
Document No.: A5E00239116 Page 15
Edition 06/05 Elastomer Bearing
Exchange
Exchange is necessary when:
• due to compression and creep in the direction of thrust only 70% of the initial
rubber thickness is reached.
• as a result of weathering several obvio us cracks per cm2 rubber surface have
formed.
• the units are strongly swollen through inadmissibl e oil spraying.
• the rubber-metal bond has been lost.
• mechanical damage is pre sent du e to the tearing p ro perties of the India rubber
that would lead to further destruction of the product.
Cleaning
It is recommended that cle aning materials with a neutral pH value be used. Materials
containing unpolarize d solvents (e.g. benzene) must not be used. The parts may be
rinsed in water after cleaning. otherwise, the bonded rubb er must be protected against
cleaning materials. The u se of sharp-edged objects, wire b rushes or sandpaper is not al-
lowed. The flat seals may never be exposed to a dire ct jet of water. The pendulum bolt
ball-head must be greased as nece ssary.
2.5 Ordering information
Elastomer bearings for
load cells with a nominal
load of
Order number
60 kg, 130 kg, 280 kg 7MH4 130-3EE11
0.5 t, 1 t 7MH4 130-4AE11
2 t, 3.5 t, 5 t 7MH4 130-4KE11
10 t, 13 t 7MH4 130-5CE11
The load cells and self-ali gning bearing bottom parts are not included in the order
numbers given above.
Document No.: A5E00239116 Page 16
3 Self-aligning Bearing
3.1 Technical description
3.1.1 Area of Application
Self-aligning bearings are used to transmit thrust directly to the load cells.
These self-center the load carrier. They offer a simple way of fitting load cells.
3.1.2 Construction
A complete self-aligning bearing consists of the order items self-aligning bearing bottom
part, load cell and self-aligning bearing top part.
Depending on the weight range, there a re two vari ants:
Weight range 60 kg to 13 t: (For numbering see Fig. 3-1)
The self-aligning bearing bottom part (1) is bolted to the foundation with four bolts. The
load cell (3) is fixed between three spring pins (2). A pressure piece (4) is set in the load
cell (3). The pendulum bolt (7) i s pla ced on this. The top plate (9) of the self-aligning
bearing top part sits on the pendulum bolt (7). The top plate (9) is bolted to the load car-
rier.
The load carrier is centered via the pendulum bolt (7). Sideways trav el of the load carrier
results in a reciprocal force that returns the load carrie r to its stable position. A flat seal
(6) between load cell (3) and top plate (9) protects the thrust piston from contamination.
Weight range 28 t and 60 t: (For numbering see Fig. 3-1)
The self-aligning bearing bottom part (1) is bolted to the foundation with four bolts. The
load cell (3) is fixed between three sprin g pins (2). A pendulum bolt unit, consisting of a
pressure piece (4) and a pendulum bolt (7) connected by a folding bello ws (5) is placed
on the thrust piston of the load cell (3). The top plate (9) of the self-aligning bea ring top
part sits on the floating
bolt (7). The top plate (9) is bolted to the load carrier.
The load carrier is centered via the pendulum bolt (7). Sideways trav el of the load carrier
results in a reciprocal force that returns the load carrier to its stable position.
Document No.: A5E00239116 Page 17
Edition 06/05 Self-aligning Bearing
RN 28 / 60 t RN 60 kg to 13 t
No. Nomenclature
1 Self-aligning bearing bottom part
2 Spring pin
3 Load cell
4 Pressure piece, load cell
5 Pendulum bolts
6 Flat seal
7 Pendulum bolt
8 Glued-in top plate pressu re piece
9 Top plate
Nominal load A
60 – 280 kg 52
0.5 – 5 t 79
10 – 13 t 121.2
28 t 203
60 t 254
Fig. 3-1 Self-aligning bearing constructi on
3.2 Fitting
Fitting situations can differ considerably. The load carrier dead weight can vary f rom a
few kilograms up to many tons. It may be, for example, a container, a platform or a rolling
road. The following fitting instructions can therefore only be of a general natu re .
WARNING
Suitable lifting tackle is to be used to raise the load carrier. The a ppropriate safety
precautions must be take n.
The load carrier should always be built on dummies to prevent the load cells being dam-
aged during installation. The load carrie r only then needs to be lifted a few millimeters
mounting plate by mounting plate to place the elastomer be arings.
Document No.: A5E00239116 Page 18
Edition 06/05 Self-aligning Bearing
Fitting procedure: (For nu mbering see Fig. 3-1)
1. Prepare load cells:
• A data sheet with calibration values is delivered with ev ery load cell. It can be
found in a transport pouch glued to the p ackaging. Remove the data sheet and
store it securely.
• Unpack the load cell.
• In the load cells (3) RN 60 kg to RN 13 t, a pressure piece (4) is set in the load
cell (3) and secured again st falling out with adh esive tape. Pull off the adhesive
tape and check that the pressure piece (4) is seated correctly.
2. Prepare self-aligning bearing bottom part:
• Unpack the self-aligning bearing bottom part (1).
3. Prepare floating cap:
• Unpack the self-aligning bearing top pa rt.
Delivery contents:
- Top plate (9)
- Pendulum bolt (7) for RN 60 kg to RN 13 t
- Pendulum bolt unit (7) for RN 28 t and RN 60 t
• Check that the flat seal (6) is seated correctly (RN 60 kg to RN 13 t only).
• Grease ball-head of pendulum bolt (7) for RN 60 kg to RN 13 t, with bearin g
grease.
• Grease ball-head of pendulum bolt (7) and thrust piston pin, for RN 28 t and
RN 60 t, with bearing grease.
4. Assembling self-aligning bearing unit:
• Place the load cell (3) betwee n the spring pins (2) in the base plat e.
NOTE
When dealing with load cells, please note Chapter 1.5 - handling of load cells.
• Place pendulum bolt (7) in the load cell (3) or, for the RN 28 t or RN 60 t, place
the pendulum bolt unit on the thrust pist on pins.
CAUTION
The RN 60, 130 and 280 kg pendulum
bolts are asymmetric. The longer
pendulum bolt pin must be inserted into
the load cell.
• Place top plate (9) on pendulum bolt (7) (only possible directly before fitting for
higher load classe s).
• To check for correct fitting and parts, me asure the total height of the bush unit
and comparing with fitting dimensions, Fig. 3-1, Page 18.
Document No.: A5E00239116 Page 19
Edition 06/05 Self-aligning Bearing
CAUTION
Wrong or incomplete fitting can result in damage to load cells, installable
components and load carrier.
DANGER
A falling load carrier can, depending on t he degree of potential danger, cause
severe bodily injury or considerable material damage.
5. Installing self-aligning bearing unit:
• Release bolts holding dummies.
• Raise load carrier at first mounting plate and remove dummy.
• Insert self-aligning beari ng unit and screw in holding bolts loosely.
• Slowly let down load carrier.
• Install remaining self-aligning bearing units as described.
• Check that the top plate is as vertical as possible above the self-aligning bearing
bottom part plate.
• Tighten up holding bolts.
Document No.: A5E00239116 Page 20
Edition 06/05 Self-aligning Bearing
3.3 Technical data
3.3.1 Functional data
Nominal load 60 kg – 5 t 10 t – 13 t 28 t – 60 t
Allowable lateral travel ± 4 mm ± 7 mm ± 10 mm
3.3.2 Dimensions
RN 28 / 60 t
RN 60 kg – 13 t
Fig. 3-2 Self-aligning bearing dimension s
Nominal load A B C D E F K ØL
60, 130, 280 kg 80 60 52 12 22 8 11 9
0.5, 1 t 100 75 79 25 25 15 10 11
2, 3.5, 5 t 100 75 79 25 30 15 8.5 11
10, 13 t 120 90 121.2 40 35 20 20 14
28 t 160 120 203 40 46 30 25 22
60 t 200 140 254 50 62 36 34 28
3.4 Care and maintenance
Self-aligning bearings must be checked according to environmental conditions. If large
amounts of dust, dirt, damp, etc., are deposite d, the service intervals should be more fre-
quent. Protect against large-scale contamination. The flat seals may never be exposed to
a direct jet of water. The pendulum bolt ball-he ad must be greased a s ne cessary.
Document No.: A5E00239116 Page 21
Edition 06/05 Self-aligning Bearing
3.5 Ordering information
Floating cap for load cells
with a nominal load of Order number
60 kg, 130 kg, 280 kg 7MH4 115-3DB11
0.5 t, 1 t 7MH4 132-4AK11
2 t, 3.5 t, 5 t 7MH4 132-4KK11
10 t, 13 t 7MH4 115-5BB11
28 t 7MH4 115-5DB11
60 t 7MH4 115-5GB11
Self-aligning bearing bottom
part for load cells with a
nominal load of
Order number
60 kg, 130 kg, 280 kg 7MH4 115-3DC11
0.5 t, 1 t, 2 t, 3.5 t, 5 t 7MH4 132-4AG11
10 t, 13 t 7MH4 115-5BC11
28 t 7MH4 115-5DC11
60 t 7MH4 115-5GC11
The load cells are not incl uded in the order numbers given above.
Document No.: A5E00239116 Page 22
4 Combination Mounting Unit
4.1 Technical description
4.1.1 Area of Application
Combination mounting units are use d to transmit thrust directly to the load cells.
These self-center the load carrier.
The combination mounting units offer the following features:
• Swing limiter integrated.
• Lift off protection integrated.
• Can be used as dummy for light fitting work.
• Slow controlled lowering of top plate by loosening the upper nut.
• Can be used to protect load cell during t ran sport by tightening top plate.
4.1.2 Construction
The combination mounting unit consists of the base plate, top plate and either one or two
countersunk bolts as swing limiter and lift off protection. Together with the load cell, it
forms a multi-functional bearing unit.
The base plate (1) is bolted to the foundation with four bolts. The load cell (7) is fixed
between three spring pins (2). A pressure piece (8) is set in the load cell (7). The pendu-
lum bolt (10) is placed on this. The top plate (6) sits o n the pendulum bolt (10). The top
plate (6) is bolted to the load carrier. The load ca rrier is centered via the pendulum bolt
(10). Sideways travel of the load carrier results in a reciprocal force that returns the load
carrier to its stable position.
The countersunk bolts (5) l imit the travel of the top plate (6). As a second function, they
prevent lifting off of the top plate.
A flat seal (9) between load cell (7) and top plate (6) protects the thrust piston from con-
tamination.
(For numbering see Fig. 4-1)
Document No.: A5E00239116 Page 23
Edition 06/05 Combination Mounting Units
RN 2 t to 13 t RN 60 kg to 1 t
Fig. 4-1 Combination Mounting Unit construction
No. Nomenclature
1 Base plate
2 Spring pin
3 Lower nut
4 Upper nut
5 Countersunk bolt
6 Top plate
7 Load cell
8 Pressure piece, load cell
9 Flat seal
10 Pendulum bolt
11 Glued-in top plate pres sure piece
Nominal load A
60, 130, 280 kg 52
0.5, 1, 2, 3.5, 5 t 79
10.13 t 121.2
4.2 Fitting
Fitting situations can differ considerably. The load carrier dead weight can vary f rom a
few kilograms up to many tons. It may be, for example, a container, a platform or a rolling
road. The following fitting instructions can therefore only be of a general natu re .
WARNING
Suitable lifting tackle is to be used to raise the load carrier. The a ppropriate safety
precautions must be take n.
The load carrier should always be built on dummies to prevent the load cells being dam-
aged during installation. The load carrie r only then needs to be lifted a few millimeters
mounting plate by mounting plate to place the elastomer be arings.
Fitting procedure: (For nu mbering see Fig. 4-1)
1. Prepare load cells:
• A data sheet with calibration values is delivered with ev ery load cell. It can be
found in a transport pouch glued to the p ackaging. Remove the data sheet and
store it securely.
• Unpack the load cell.
• A pressure piece (8) is set in the load cell (7) and secured against falling out with
adhesive tape. Pull off the adhesive tape and check t hat the pressure
piece (8) is seated correctly.
Document No.: A5E00239116 Page 24
Edition 06/05 Combination Mounting Units
2. Prepare combination mounting unit:
NOTE
The lifting path of the top plate (6) must be set with the countersunk bolts (5).
Setting this lifting path is easier if performed before installing the load cell. The
combination mounting unit must be disa ssembled before installing in the load
cell.
The combination mounting units are pre-assembl ed before delivery. Adjust the
top plate (6) using the countersunk bolts (5) and the nuts (3) and (4) to the
following mounting height:
Rated load 60 … 280 kg 0.5 … 5 t 10 t, 13 t
Functional installing height 52 mm 79 mm 121.2 mm
+ lifting distance 3 mm 3 mm 5.0 mm
= mounting height 55 mm 82 mm 126.2 mm
These preparations and following prevent any extra work in adjusting later.
When using the combinati on mounting units as dummies, the extra height must
be taken into account.
• Unpack combination mounting unit.
Delivery contents:
- Combination mounting unit, assembled
- Pendulum bolt (10)
• Set the mounting height of the top plate (6) as described above.
• Screw upper nut (4) up to lower nut (3) and lock.
• Loosen lower nut (3) and unscrew countersunk bolt (5) from base plate (1).
Leave countersunk bolt (5) in top plate (6) and lay top plate (6) aside.
• Check that the flat seal (9) is seated correctly.
• Apply bearing grease to pendulum b olt ball-head (10).
3. Reassembling combination mounting unit:
• Place the load cell (7) betwee n the spring pins (2) in the base plat e (1).
NOTE
When dealing with load cells, please note Chapter 1.5 - handling of load cells.
• Place pendulum bolt (10) in the load cell (7).
CAUTION
The RN 60, 130 and 280 kg
pendulum bolts are asymmetric. The
longer pendulum bolt pin must be
inserted into the load cell.
Document No.: A5E00239116 Page 25
Edition 06/05 Combination Mounting Units
• Place top plate (6) sits on pendulum bolt (10).
• Screw countersunk bolt (5) into top plate (3) and tighte n lower nut (3).
The countersunk bolts (5) may not protrude above the top plate (1).
• Check top plate (6) for 1.5 to 2 mm travel and adjust if necessary.
• To check for correct fitting and parts, me asure the total height of the bearing unit
and compare with fitting dimensions, Fig. 4-1, Page 24.
• Loosen upper nut (4) and tighten up against top plate (6). The top plate (6) is
then centered relative to the base plate (1).
CAUTION
Wrong or incomplete fitting can result in damage to load cells, installable
components and load carrier.
DANGER
A falling load carrier can, depending on t he degree of potential danger, cause
severe bodily injury or considerable material damage.
4. Install combination mounting unit:
• Release bolts holding dummies.
• Raise load carrier at first mounting plate and remove dummy.
• Insert combination mounting unit and screw in holding bolts loosely.
• Slowly let down load carrier.
• Install remaining combination mounting units as described.
• Tighten up holding bolts.
• Loosen upper nut (4) and slowly lower top plate (6).
• Screw upper nut (4) up to lower nut (3) and tighten.
5. Check installation:
• The load carrier must be able to swing freely.
• The countersunk bolts (5) must not be within the top plate (6) drill holes.
• The top plate (6) must be as vertical as possible above the base plate (1).
4.3 Technical data
4.3.1 Functional data
Nominal load 60 kg – 5 t 10 t – 13 t
Permitted lateral travel: ± 3 mm ± 4.5 mm
Top plate lift travel 3 – 4 mm 4.5 – 5.5 mm
Max. lateral force 10 kN
Max. lift force 25 kN
Document No.: A5E00239116 Page 26
Edition 06/05 Combination Mounting Units
4.3.2 Dimensions
RN 60 kg to 1 t RN 2 t to 13 t
Nominal load A B C ØD E F ØG H J K
60, 130, 280 kg 80 118 60 9 40 57 39 8 12 52
0.5, 1 t 100 145 75 11 50 68 48 15 25 79
2, 3.5, 5 t 100 190 75 11 136 48 15 25 79
10, 13 t 120 210 90 14 155 45 20 40 121.2
Fig. 4-2 Combination mounting unit dimensions
4.4 Care and maintenance
Combination mounting units must be checked according to environmental conditions. If
large amounts of dust, dirt, damp, etc., are deposited, the service intervals should be
more frequent. Protect against large-sca le contamination. The flat seals may never be
exposed to a direct jet of water. The pendulum bolt ball-head mu st be greased as neces-
sary.
4.5 Ordering information
Combination mounting unit
for load cells with a
nominal load of
Order number
60 kg, 130 kg, 280 kg 7MH4 125-3DA11
0.5 t, 1 t 7MH4 132-4AC11
2 t, 3.5 t, 5 t 7MH4 132-4KC11
10 t, 13 t 7MH4 125-5BA11
The load cells are not incl uded in the order numbers given above.
Document No.: A5E00239116 Page 27
5 Guide Element for Combination Mounting Unit
5.1 Technical description
5.1.1 Area of Application
Guide elements are used if horizontal forces occur during weighing or if general move-
ment of the load carrier must be prevented. They are used together with the combination
mounting unit.
Arrangement of the guide elements for various load carriers is shown in Figs. 5-1 and 5-2.
Fig. 5-1 Guide elements for round an d square mounting
Combination mounting unit
with guide element Combination mounting unit
without guide element
Document No.: A5E00239116 Page 28
Edition 06/05 Guide Element for Combination Mounting Unit
Fig. 5-2 Guide elements for oblong mou nting
5.1.2 Construction
The guide element consists of two flanges (3) bolted to the top plate (7) and the base
plate (1) of the combination mounting unit. Both flanges (3) are kept at the required dis-
tance by two universal joints (4) with left and right hand threads and a spacer arm (6).
The distance is set with the spacer arm (6). Two locknuts (5) prevent twisting of the uni-
versal joints (4).
Fig. 5-3 Guide element construction
No. Nomenclature
1 Base plate
2 M8 fixing bolt (4x)
3 Flange
4 Universal joint (1x left, 1x right hand thread)
5 Locknut (1x left, 1x right hand thread)
6 Spacer arm, right/left hand thread
7 Top plate
Document No.: A5E00239116 Page 29
Edition 06/05 Guide Element for Combination Mounting Unit
5.2 Fitting
The guide elements are delivered set to the optimum length. If the combination mounting
unit is lined up correctly at installation, the guide elements can be fitted immediately.
It is important that the guide elements do not introduce additional lateral forces. To avoid
this as far as possible, it is recommended that the length of the guide element is not
changed or adjusted after fitting. This implies that the length shoul d be adjusted before
fitting the guide element. If correctly fitted, the flange (3) holes match up to the threaded
holes in the top plate (7) and the base pl ate (1). No change in length is caused by
bolting the guide element to the combination mountin g unit. The M8 fixing bolts (2) must
be tightened to 23 Nm. Check the guide elements after fitting. The universal joints (4)
must be easy to turn with any load on the load carrier.
(For numbering see Fig. 2-1)
Document No.: A5E00239116 Page 30
Edition 06/05 Guide Element for Combination Mounting Unit
5.3 Technical data
5.3.1 Functional data
Permitted horizontal force: 1.7 kN
Tightening torque for M8 fixing bolts: 23 Nm
5.3.2 Dimensions
Nominal load A B C D E ØF ØG H J K L
0.5, 1 t 100 145 75 12.5 27 11 48 140 15 25 79
Fig. 5-4 Guide element dimensions RN 0.5, 1 t
Document No.: A5E00239116 Page 31
Edition 06/05 Guide Element for Combination Mounting Unit
Nominal load A B C D ØE ØF G H J K
2, 3.5, 5 t 100 190 75 136 48 11 140 79 15 25
10, 13 t 120 210 90 155 45 14 160 121,2 20 40
Fig. 5-5 RN 2 to 13 t guide element
5.4 Care and maintenance
The guide elements must be protected a gainst contamination. They are normally mainte-
nance-free. With dynami cally changing loads, the guide elements should be regularly
checked.
5.5 Ordering information
Guide element for load
cells with a nominal load of Order number
0.5 t, 1 t 7MH4 132-4AQ12
2 t, 3.5 t, 5 t 7MH4 132-4KQ12
10 t, 13 t 7MH4 134-5BQ12
The load cells and combi nation mounting units are not included in the order num bers
given above.
Document No.: A5E00239116 Page 32
6 Grounding Cable
6.1 Technical description
6.1.1 Area of Application
The grounding cable is used to protect the load cell against undesirable currents. Such
current can, for example, be caused by:
• equalization current caused by missing or faulty potential equali zation cabling
• lightning strikes in the vicinity
• welding work
• static charge.
The grounding cable repre sents an electrical sub-circuit for the load cell an d mounting
unit. High welding currents can destroy the load cell, the mounting unit or the electronics.
Voltage flashovers due to static discharge can destro y the electronics.
Groundin
g
cable
6.1.2 Construction
Fig. 6-1 Grounding cable usage example
The grounding cable consists of a fine-wire copper cable with a cross-section o f 50 mm2
and two eyelets, Ø 10 mm.
6.2 Fitting
For grounding cable attachment a bolt e.g. M10, with good long-term contact properties
should be bolted up to the load carrier and the foundation.
Document No.: A5E00239116 Page 33
Edition 06/05 Earth Cable
6.3 Dimensions
2 thick
Fig. 6-2 Grounding cable dimen sion s
6.4 Care and maintenance
The attachment points must be regularly checked for conductance and corrosi on.
6.5 Ordering information
Nomenclature Order number
Grounding cable 7MH3 701-1AA1
Document No.: A5E00239116 Page 34
