s SIWAREX R RN Series of Mounting Units Operating Instructions Edition 06/2005 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 3.2 3.3 3.3.1 3.3.2 3.4 3.5 4 4.1 4.1.1 4.1.2 4.2 4.3 4.3.1 4.3.2 4.4 4.5 5 5.1 5.1.1 5.1.2 5.2 5.3 5.3.1 5.3.2 5.4 5.5 6 6.1 6.1.1 6.1.2 6.2 6.3 6.4 6.5 Construction ...................................................................................... 17 Fitting................................................................................................. 18 Technical data ................................................................................... 21 Functional data .................................................................................. 21 Dimensions........................................................................................ 21 Care and maintenance ...................................................................... 21 Ordering information .......................................................................... 22 Combination Mounting Unit............................................................ 23 Technical description ......................................................................... 23 Area of Application ............................................................................ 23 Construction ...................................................................................... 23 Fitting................................................................................................. 24 Technical data ................................................................................... 26 Functional data .................................................................................. 26 Dimensions........................................................................................ 27 Care and maintenance ...................................................................... 27 Ordering information .......................................................................... 27 Guide Element for Combination Mounting Unit ............................ 28 Technical description ......................................................................... 28 Area of Application ............................................................................ 28 Construction ...................................................................................... 29 Fitting................................................................................................. 30 Technical data ................................................................................... 31 Functional data .................................................................................. 31 Dimensions........................................................................................ 31 Care and maintenance ...................................................................... 32 Ordering information .......................................................................... 32 Grounding Cable ............................................................................. 33 Technical description ......................................................................... 33 Area of Application ............................................................................ 33 Construction ...................................................................................... 33 Fitting................................................................................................. 33 Dimensions........................................................................................ 34 Care and maintenance ...................................................................... 34 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 personal injury can occur if proper precautions are not taken. CAUTION without the triangle means that material damage can occur if proper precautions 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 recommendation is followed. Qualified personnel in the sense of the safety notes in this operation 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 and maintain devices, systems and circuitry in accordance with international regulations for safety. Copyright (c) Siemens AG 2005 All rights reserved Exclusion of liability 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. 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 Automation & Drives Division Process Instrumentation and Analytics Department D-76181 Karlsruhe, Germany Document No.: A5E00239116 (c) Siemens AG 2005 Technical data subject to change. 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 purpose 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 device can only be ensured if the specifications provided in technical data are observed. Improper handling can result in death, severe personal injury and property damage. Notes on product liability We expressly point out that the nature of the product is described exclusively and conclusively in the contract of sale. The contents 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 container 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 document. 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 before starting work! It contains important information 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 measuring 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 overloading of fixed installation load cells by pulling in the opposite direction to the measurement direction. Lift off protections are necessary if there is a danger 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 incorporated into the combined mounting units in the RN series. It may be necessary to construct 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 possible lift travel of the load carrier. The hole diameter OD must be considerably greater than the bolt diameter Od. 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 excessive 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 series 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 account 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 operations, 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 carrier or a change in its length due to heating. They generate, depending on the degree 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 or elastomer bearing up to the limit of travel, appropriate safety measures must be 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 Requirements Swing limiters must be constructed or adjusted such that the allowable degree of swing in all axes cannot be exceeded. This is shown in two examples in Fig. 1-2. Drill hole 4 Platform 2.8 2.8 Bolt Platform 4 Limit stop 4 4 Two examples of weigh platform swing limiting with an allowable travel of 4 mm. Fig. 1-2 Example of swing limiting Swing limiters are integrated into the combined mounting units in the RN series. CAUTION When using load cells with small nominal loads, overload protectors should be used, also laterally, to prevent damage to the load cells. Using load cells above their maximum operating or lateral load rating can result in irreparable damage, including shearing of the load cell or the fitted unit. 1.3 Guide elements Guide elements directly take up lateral forces. They 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 are ideally 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 components are created in the weighing direction. Strain on the anchors can be most easily avoided by when these are fitted with the same direction of rotation. Three guide elements are sufficient to restrain a weighing platform or container. Use of four anchors can bring the great danger of tensioning these relative to one another and thereby inducing a measurement error. If, however, four guide elements must be used, these must be fitted with enough play. The guide elements used must follow established weighing technology principles. For the SIWAREX R RN series of combination mounting units, ball joint guide elements up to 1.7 kN are available for the weight class 500 kg to 13 t. Upon request, ball pin guide elements can be delivered up to 1000 kN lateral force. Document No.: A5E00239116 Page 7 Edition 06/05 1.4 General Construction and Installation Requirements 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 installation they should be therefore 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 combination 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 between the upper 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 most stable solution. Heavy fitting work can be carried out. 3. Use a SIWAREX R combination mounting unit. The combination mounting units are delivered 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 units 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 danger. CAUTION To protect against unwanted electrical currents, such as those produced by welding 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 connected up by qualified personnel. Load cells are precision units and must be handled delicately. This must be particularly taken into account when transporting and fitting. Document No.: A5E00239116 Page 8 Edition 06/05 General Construction and Installation Requirements 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-center loading and lateral loading introduce errors that on one hand give false measurement results and on the other cam damage the load cell or fitted element if the permissible limits are exceeded. Mounting units in general allow enough play such that thermal expansion does not lead to lateral loading. 1.6 Welding and fitting As long as all fitting work on scales construction has not been concluded, the load cells should be replaced by dummies to protect them from shock or welding currents. CAUTION If welding is necessary after fitting the load cells, care 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 location. The load cells must be bridged across with an grounding cable. Each load cell must be disconnected. 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 cells with low nominal loads, that attaching thrust pistons can bend the load cell body, e.g. by the tightening of locknuts. WARNING Suitable lifting tackle is to be used to raise the load carrier. The appropriate safety precautions must be taken. NOTE The load carrier should 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 desired load. They must be capable of allowing an increase in weight up to the nominal value. Overload protectors are to be protected against dirt and icing up. Document No.: A5E00239116 Page 9 Edition 06/05 General Construction and Installation Requirements 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 measurement due to blockage or an overflow of the scales, with possible ensuing material damage or bodily injury. CAUTION Correct fitting of load cells and fitted elements is to be checked, for example by inspecting the fitting tolerances and swing travel. Faulty 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 cable 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 absolutely firm and free from subsidence. Flat steel plates, on which the fitted elements are mounted, must be cast 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 distribution is mostly statically indeterminate. With firm foundations and stiff load carriers, the load 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 follows: 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 Requirements * The mounting plate of the load cell with the lowest value should be 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, absolutely clean. The thrust piston mating surfaces must be coated 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 iced up in operation, appropriate check and/or sealing is necessary. The underside can, for example, be protected by a greased seal or a non-hardening sealing compound. It should be remembered when taking such measures that the thrust pistons on the upper side of the load cell should also be well sealed to effectively prevent the ingress of moisture. 1.10 De-installation The same security precautions and requirements apply to de-installation as for installation 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 and remove carefully without using force. Do not cut the cabling if the load cell is to be reused or sent for repair. 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 protects the load cell when shock-type loads or vibrations may occur. 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 bearing 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) and 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. RN 60 to 280 kg No. 1 2 3 4 5 6 7 Nomenclature Self-aligning bearing bottom part Spring pin Load cell Pressure piece, load cell Pendulum bolts Flat seal Elastomer bearing RN 0.5 to 13 t Nominal load 0.5, 1 t 2, 3.5, 5 t 10, 13 t A 97 102 120 Fig. 2-1 Elastomer bearing construction Document No.: A5E00239116 Page 12 Edition 06/05 2.2 Elastomer Bearing Fitting Fitting situations can differ considerably. The load carrier dead weight can vary from 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 nature. WARNING Suitable lifting tackle is to be used to raise the load carrier. The appropriate safety precautions must be taken. The load carrier should always be built on dummies to prevent the load cells being damaged during installation. The load carrier only then needs to be lifted a few millimeters mounting plate by mounting plate to place the elastomer bearings. Fitting procedure: (For numbering see Fig. 2-1) 1. Prepare load cells: * A data sheet with calibration values is delivered with every load cell. It can be found in a transport pouch glued to the packaging. 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 that 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 bolt ball-head (5). 4. Assembling elastomer bearing unit: * Place the load cell (3) between the spring pins (2) in the base plate. 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, measure 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 the 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 bearings are not under tension. * Tighten up holding bolts. 2.3 Technical data 2.3.1 Functional data Nominal load Allowable lateral travel 60 kg - 5t 4 mm 10 t - 13 t 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 0,5, 1 t 2, 3,5, 5 t 10,13 t A 100 120 120 B C OD 75 97 85 90 102 100 90 120 100 E 25 30 35 F 15 15 20 G H 6 100 6 100 6 120 K OL 75 11 75 11 90 11 M 11 11 14 N 9,5 8,5 20 Fig. 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 products. They 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 rubber products remain unchanged in their physical properties 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 with a blunt "testing iron" (pressing side with a radius). If partial edge loosening in the bonded area between the elastomer and the metal or surface 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 obvious cracks per cm2 rubber surface have formed. * the units are strongly swollen through inadmissible oil spraying. * the rubber-metal bond has been lost. * mechanical damage is present due to the tearing properties of the India rubber that would lead to further destruction of the product. Cleaning It is recommended that cleaning materials with a neutral pH value be used. Materials containing unpolarized solvents (e.g. benzene) must not be used. The parts may be rinsed in water after cleaning. otherwise, the bonded rubber must be protected against cleaning materials. The use of sharp-edged objects, wire brushes or sandpaper is not allowed. The flat seals may never be exposed to a direct jet of water. The pendulum bolt ball-head must be greased as necessary. 2.5 Ordering information Elastomer bearings for load cells with a nominal load of 60 kg, 130 kg, 280 kg 0.5 t, 1 t 2 t, 3.5 t, 5 t 10 t, 13 t Order number 7MH4 130-3EE11 7MH4 130-4AE11 7MH4 130-4KE11 7MH4 130-5CE11 The load cells and self-aligning 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 are two variants: 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) is placed 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 carrier. The load carrier is centered via the pendulum bolt (7). Sideways travel of the load carrier results in a reciprocal force that returns the load carrier 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 spring pins (2). A pendulum bolt unit, consisting of a pressure piece (4) and a pendulum bolt (7) connected by a folding bellows (5) is placed on the thrust piston of the load cell (3). The top plate (9) of the self-aligning bearing 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 travel 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 60 kg to 13 t No. 1 2 3 4 5 6 7 8 9 Nomenclature Self-aligning bearing bottom part Spring pin Load cell Pressure piece, load cell Pendulum bolts Flat seal Pendulum bolt Glued-in top plate pressure piece Top plate RN 28 / 60 t Nominal load 60 - 280 kg 0.5 - 5 t 10 - 13 t 28 t 60 t A 52 79 121.2 203 254 Fig. 3-1 Self-aligning bearing construction 3.2 Fitting Fitting situations can differ considerably. The load carrier dead weight can vary from 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 nature. WARNING Suitable lifting tackle is to be used to raise the load carrier. The appropriate safety precautions must be taken. The load carrier should always be built on dummies to prevent the load cells being damaged during installation. The load carrier only then needs to be lifted a few millimeters mounting plate by mounting plate to place the elastomer bearings. Document No.: A5E00239116 Page 18 Edition 06/05 Self-aligning Bearing Fitting procedure: (For numbering see Fig. 3-1) 1. Prepare load cells: * A data sheet with calibration values is delivered with every load cell. It can be found in a transport pouch glued to the packaging. 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 against falling out with adhesive 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 part. 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 bearing 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) between the spring pins (2) in the base plate. 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 piston 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 classes). To check for correct fitting and parts, measure 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 the 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 bearing 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 3.3 Self-aligning Bearing Technical data 3.3.1 Functional data Nominal load Allowable lateral travel 60 kg - 5 t 10 t - 13 t 4 mm 7 mm 28 t - 60 t 10 mm 3.3.2 Dimensions RN 28 / 60 t RN 60 kg - 13 t Nominal load 60, 130, 280 kg 0.5, 1 t 2, 3.5, 5 t 10, 13 t 28 t 60 t A 80 100 100 120 160 200 B 60 75 75 90 120 140 C 52 79 79 121.2 203 254 D 12 25 25 40 40 50 E 22 25 30 35 46 62 F 8 15 15 20 30 36 K OL 11 9 10 11 8.5 11 20 14 25 22 34 28 Fig. 3-2 Self-aligning bearing dimensions 3.4 Care and maintenance Self-aligning bearings 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-scale contamination. The flat seals may never be exposed to a direct jet of water. The pendulum bolt ball-head must be greased as necessary. Document No.: A5E00239116 Page 21 Edition 06/05 3.5 Self-aligning Bearing Ordering information Floating cap for load cells with a nominal load of 60 kg, 130 kg, 280 kg 0.5 t, 1 t 2 t, 3.5 t, 5 t 10 t, 13 t 28 t 60 t Self-aligning bearing bottom part for load cells with a nominal load of 60 kg, 130 kg, 280 kg 0.5 t, 1 t, 2 t, 3.5 t, 5 t 10 t, 13 t 28 t 60 t Order number 7MH4 115-3DB11 7MH4 132-4AK11 7MH4 132-4KK11 7MH4 115-5BB11 7MH4 115-5DB11 7MH4 115-5GB11 Order number 7MH4 115-3DC11 7MH4 132-4AG11 7MH4 115-5BC11 7MH4 115-5DC11 7MH4 115-5GC11 The load cells are not included 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 used 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 transport 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 pendulum bolt (10) is placed on this. The top plate (6) sits on the pendulum bolt (10). The top plate (6) is bolted to the load carrier. The load carrier 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) limit 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 contamination. (For numbering see Fig. 4-1) Document No.: A5E00239116 Page 23 Edition 06/05 Combination Mounting Units RN 60 kg to 1 t No. 1 2 3 4 5 6 7 8 9 10 11 Nomenclature Base plate Spring pin Lower nut Upper nut Countersunk bolt Top plate Load cell Pressure piece, load cell Flat seal Pendulum bolt Glued-in top plate pressure piece RN 2 t to 13 t Nominal load 60, 130, 280 kg 0.5, 1, 2, 3.5, 5 t 10.13 t A 52 79 121.2 Fig. 4-1 Combination Mounting Unit construction 4.2 Fitting Fitting situations can differ considerably. The load carrier dead weight can vary from 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 nature. WARNING Suitable lifting tackle is to be used to raise the load carrier. The appropriate safety precautions must be taken. The load carrier should always be built on dummies to prevent the load cells being damaged during installation. The load carrier only then needs to be lifted a few millimeters mounting plate by mounting plate to place the elastomer bearings. Fitting procedure: (For numbering see Fig. 4-1) 1. Prepare load cells: * A data sheet with calibration values is delivered with every load cell. It can be found in a transport pouch glued to the packaging. 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 that 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 disassembled before installing in the load cell. The combination mounting units are pre-assembled 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 Functional installing height + lifting distance = mounting height 60 ... 280 kg 52 mm 3 mm 55 mm 0.5 ... 5 t 79 mm 3 mm 82 mm 10 t, 13 t 121.2 mm 5.0 mm 126.2 mm These preparations and following prevent any extra work in adjusting later. When using the combination 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 bolt ball-head (10). 3. Reassembling combination mounting unit: * Place the load cell (7) between the spring pins (2) in the base plate (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 tighten 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, measure 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 the 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: * * * 4.3 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). Technical data 4.3.1 Functional data Nominal load Permitted lateral travel: Top plate lift travel Max. lateral force Max. lift force Document No.: A5E00239116 60 kg - 5 t 10 t - 13 t 3 mm 4.5 mm 3 - 4 mm 4.5 - 5.5 mm 10 kN 25 kN Page 26 Edition 06/05 Combination Mounting Units 4.3.2 Dimensions RN 60 kg to 1 t Nominal load 60, 130, 280 kg 0.5, 1 t 2, 3.5, 5 t 10, 13 t RN 2 t to 13 t A 80 100 100 120 B 118 145 190 210 C OD 60 9 75 11 75 11 90 14 E 40 50 F OG 57 39 68 48 136 48 155 45 H 8 15 15 20 J 12 25 25 40 K 52 79 79 121.2 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-scale contamination. The flat seals may never be exposed to a direct jet of water. The pendulum bolt ball-head must be greased as necessary. 4.5 Ordering information Combination mounting unit for load cells with a nominal load of 60 kg, 130 kg, 280 kg 0.5 t, 1 t 2 t, 3.5 t, 5 t 10 t, 13 t Order number 7MH4 125-3DA11 7MH4 132-4AC11 7MH4 132-4KC11 7MH4 125-5BA11 The load cells are not included 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 movement 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. Combination mounting unit with guide element Combination mounting unit without guide element Fig. 5-1 Guide elements for round and square mounting Document No.: A5E00239116 Page 28 Edition 06/05 Guide Element for Combination Mounting Unit Fig. 5-2 Guide elements for oblong mounting 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 distance 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 universal joints (4). No. 1 2 3 4 5 6 7 Nomenclature Base plate M8 fixing bolt (4x) Flange Universal joint (1x left, 1x right hand thread) Locknut (1x left, 1x right hand thread) Spacer arm, right/left hand thread Top plate Fig. 5-3 Guide element construction Document No.: A5E00239116 Page 29 Edition 06/05 5.2 Guide Element for Combination Mounting Unit 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 should 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 plate (1). No change in length is caused by bolting the guide element to the combination mounting 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 5.3 Guide Element for Combination Mounting Unit Technical data 5.3.1 Functional data Permitted horizontal force: Tightening torque for M8 fixing bolts: 1.7 kN 23 Nm 5.3.2 Dimensions Nominal load 0.5, 1 t A 100 B 145 C D 75 12.5 E OF OG 27 11 48 H 140 J 15 K 25 L 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 2, 3.5, 5 t 10, 13 t A 100 120 B 190 210 C 75 90 D OE OF G 136 48 11 140 155 45 14 160 H 79 121,2 J 15 20 K 25 40 Fig. 5-5 RN 2 to 13 t guide element 5.4 Care and maintenance The guide elements must be protected against contamination. They are normally maintenance-free. With dynamically changing loads, the guide elements should be regularly checked. 5.5 Ordering information Guide element for load Order number cells with a nominal load of 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 combination mounting units are not included in the order numbers 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 equalization cabling * lightning strikes in the vicinity * welding work * static charge. The grounding cable represents an electrical sub-circuit for the load cell and mounting unit. High welding currents can destroy the load cell, the mounting unit or the electronics. Voltage flashovers due to static discharge can destroy the electronics. Grounding cable Fig. 6-1 Grounding cable usage example 6.1.2 Construction The grounding cable consists of a fine-wire copper cable with a cross-section of 50 mm2 and two eyelets, O 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 6.3 Earth Cable Dimensions 2 thick Fig. 6-2 Grounding cable dimensions 6.4 Care and maintenance The attachment points must be regularly checked for conductance and corrosion. 6.5 Ordering information Nomenclature Grounding cable Document No.: A5E00239116 Order number 7MH3 701-1AA1 Page 34