RC3. LOADCELLS. Technical specification. FLINTAB is exclusive importer in Romania of FLINTEC Germany products.

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1 LOADCELLS The FLINTAB Sweden loadcells innovation reorganised then by FLINTEC Germany is legendary, their design gaining the first place in the world and spectacular patents. Their pioneering force and weighing solutions established an unequaled performance standard. WEIGHBRIDGES Technical specification FLINTAB is exclusive importer in Romania of FLINTEC Germany products. is internationally recognized as a benchmark for all high capacity loadcells. loadcells are available from 7.5t to 300t range and they are classified GP, C1, C3, C4 and C3 MI 8 according to OIML R 60; NTEP nmax= Made of stainless steel and hermetically sealed, they are ideal for the most hostile industrial environments. FLINTEC loadcells are designed to satisfy the most strict accuracy requirements. is one of the most prestigious loadcell international trademarks and is always in the top of the best loadcells. It s certifications were obtained from all over the world metrological authorities. The unique design of the loadcell and the mechanical ensemble which transfers the forces through self-aligning ROCKER COLUMN concept leads to an excelent measurement of the load and minimum dimensions of the mounting kit. FLINTEC calibration technique (mv/v/ω) eliminates the corner calibration problems in multi-weighing systems, moreover, time-consumer at the metrological verifications. Optionally, is available for explosion risks environments 0, 1, 2 (gas) and 20, 21, 22 (dust) according to EEx ia IIC T6..T4 T130 C ATEX. > > Capacity from 7.5t to 300t > > Remarkable accuracy > > Stainless steel design > > True hermetic sealing > > IP68, IP69K protection > > Lightning protection: electronic gas discharge tubes > > High input resistance: 1100 Ohm > > Metrological certification for 4000 intervals

2 LOADCELLS TECHNICAL SPECIFICATIONS / DIMENSIONS Maximum capacity (Emax) t 7.5/15/22.5/30/ 40/50/100/ 150/ /15/22.5/30/40/50 Minimum dead load (Emin) 2%xEmax Accuracy class according to OIML R60 (GP) C1 C3 C3 MI 8 C4 Maximum number of verification intervals (NLC) Minimum load cell verification interval (Vmin) - Emax/5000 Emax / Temp. effect on minimum dead load output (TC0) %xro/10 C ± ± ± Temperature effect on sensitivity (TCRO) %xro/10 C ± ± ± ± Combined error %xro ± ± ± ± ± Non-linearity %xro ± ± ± ± ± Hysteresis %xro ± ± ± ± ± Creep error (30 minutes) / DR %xro ± ± ± ± ± Rated Output (RO) mv/v 2 ± 0.1% Calibration in mv/v/ω (A...I classified) % ± 0.05 ( ± 0.005) Zero balance %xro ± 5 Excitation voltage V Input resistance (RLC) Ω 1150±50 Output resistance (Rout) Ω 1000±2 Insulation resistance (100 V DC) MΩ 5000 Safe load limit (Elim) %xemax 200 Ultimate load %xemax 300 Compensated temperature range C Operating temperature range C (ATEX ) Loadcell material stainless steel 17-4 PH (1,4548) Sealing complete hermetic sealing; cable entry sealed by glass to metal header Protection according EN IP68 (up to 2 m water depth) / IP69K The limits for Non-Linearity, Hysteresis, and TCRO are typical values. The sum of Non-linearity, Hysteresis and TCRO meets the requirements according to OIML R60 with plc=0.7. CONNECTIONS Loadcell is provided with a 4 wires shielded cable. (AWG 24 for t / AWG 20 for t). Polyurethane coating. 2 Dimensions in mm for -30t Cable length: For t 12m For t 18m Cable diameter: For t 5mm For t 7.8mm The shield is not connected (optionally, it may be soldered to the loadcell body). + Excitation (green) + Signal (white) + Shield (yellow) - Excitation (black) - Signal (red)

3 For installation, are needed only the inferior and superior loadcups and simple vertically-align elements. MOUNTING KIT ADVANTAGES: > easy mounting and alignment > the platform must be lifted only 1-2mm for loadcells installation EXPANDED LOADCELL KIT JUNCTION BOX AND CABLE > Junction box: fiberglass reinforced polyester FRP according to DIN 16913, protection level IP66, operating temperature -40 C..+90 C, IP68 cable glands, silica gel. > Electronic board equipped with gas discharge tubes for lightning protection. > Copper reinforced connection cable, PVC coated, with an increased delay of fire propagation CSYEAbY (F) 7x1mm. 3

4 LOADCELLS TRUE HERMETIC SEALING Why are the loadcells hermetically sealed? Loadcells function principle is based on strain gauges. The resistive strain gauges are fixed on the maximum effort surface and a Wheatstone bridge circuit realises the voltage-resistivity conversion. Strain gauges are sensitive components, so they must be protected from mechanical deformations, humidity and chemical substances. Although a resonable protection is possible using modern cases, it s known that the best solution is hermetic sealing to protect both strain gauges and the compensation elements. loadcells, through their stainless steel design and true hermetic sealing, are the right choice for using in harsh working environments. WHAT IS TRUE HERMETIC SEALING? Hermetic sealing related to loadcell is acomplished when all loadcell elements are completely isolated into a case. This quality is ensured through some welding points strategically positioned relative to the housing and through the stainless steel qualities and compensation elements. CONSTRUCTIVE WAY The following scheme illustrates the most important components of the loadcell, begining with the stainless steel element (column type) which includes the resistive strain gauges. This is the first encapsulated and connected element. Then, the stainless steel housing and the diaphragm are both welded to the column for maximum protection. The loadcell is tested and calibrated. After the final calibration, the cable is welded to it s place to ensure the perfect hermetic sealing, checked by the helium leak detection system. Using a metal tube, vacuum is created inside the loadcell case. After that, on the exterior loadcell surface, especially in the welded areas is blown helium gas. If the loadcell is not perfectly sealed, then the gas will be absorbed into the loadcell case and it will be detected by the system. If not, means that the loadcell is perfectly sealed and is filled up with nitrogen and sealed for the last time. The result is a true hermetic sealed loadcell. Housing Loadcell column element Resistive strain gauge (x4) Diaphragm CABLE COATING DETAILS THE MAIN COMPONENTS Welding 1: welded round around for hermetic sealing Final welding: welded round around for true hermetic sealing Cable coating Welding 2: welded round around for hermetic sealing 4 Warning: This perfect hermetic sealing design allows easy replacement of the cable in case of damage. Electronic board with calibration and compensation resistors Head welded to base Cable connection pins (x4) Metal tube for helium leak detection Glass to metal header Welding

5 The 5 comparision criteria of FLINTEC loadcell: Tested to helium leaks. Filled with dry nitrogen - eliminates the corrosion effects of strain gauges. Long time high stability. Cable gland: glass to metal = easy fixing of the cable. After sealing, fine external adjustment of the TC-Zero AND TC-Span parameters Y factor value up to ) Y-Factor=Emax/vmin. LOADCELL CABLE The electric 4-wire cable is shielded. The shield is not connected to the loadcell body. Cable factory installation is acomplished in three steps: 1. Connecting the cable to the soldered terminals. 2. Installing the O-rings and the adapter. 3. Filling the adapter with a special material and installing the cable connector. After the last step, the ensemble protection is according to IP 68 STANDARD. Step 1 The loadcell cable is soldered and isolated with head shrink tubes. Step 2 O-rings and adapter are installed. Step 3 The adapter is filled with a special gel, the rubber garnish and sealing cover of the cable gland are installed. 5

6 LOADCELLS PERFORMANCE The loadcell performance depends exclusively of the synergy between the technical concept and the load introduction. ROCKER COLUMN (RC) loadcells are way superior and they should not be cofused with compresion loadcells (Multi-column Compression Load Cells). TECHNICAL CONCEPT All loadcells uses resistive strain gauges with column linearization, except of those which uses A/D converters. There is no advantages in favor of any solution. Hysteresis and creep depends of: > material choosing > strain gauges choosing > heat treatment The best practice is using the stainless steel alloys, strain gauges with negative hysteresis (to compensate the residual positive hysteresis after the heat treatment) and a complex termic treatment process. Every ROCKER COLUMN loadcell is individually creep tested. 6 mv/v/ohm and mv/v calibration values represents an determinant factor in the loadcells selection process. These values importance is double: 1) The loadcells may be replaced without readjusting the corners or the sections. 2) The loadcells may be replaced without weighing system recalibration. CAPACITY 30t There are compression loadcells offerts (not recommended) and 20t/loadcell capacity. 20t x 4 loadcells mounted on a platform section = 80t Platform section weight of 20t + maximum loaded truck 60t = 80t Means that the loadcells are working at their highest limit, where the hysteresis curve is not linear. 30t/loadcell capacity is the only one who sets the scale functioning to the middle of the domain (50..60%) where this curve is linear! 30t x 4 = 120t >> t 30t

7 LOAD INTRODUCTION The way in which the load is introduced in the loadcell structure is just as important like the design. ROCKER COLUMN loadcells are built with spheric loading surfaces for load introduction, spaced correctly by the strain gauges, to avoid the propagated forces from the maximum areas. LOAD INTRODUCTION MULTI-DIRECTIONAL BALANCE A true ROCKER COLUMN loadcell has two radial loading surfaces, one with a large ray in the center where it s made the load measuring, and a small one to the edge where the appears the balance. This design provides the best load introduction invented in the world, until now, by the FLINTAB Sweden founders, now named FLINTEC. FLINTAB Romania took the whole know-how of the group. Because the ROCKER COLUMN loadcell balances, the forces generated by the dilatations and the contractions of the platform are absorbed by this balance. Similarly, the platform deflection errors are minimized too. The ROCKER COLUMN loadcells are electrically compensated to obtain the measurement accuracy when the loadcell balanced into a non-vertical position. Some manufacturers provides an offset load compensation through the sensitive element, others totally ignores the offset error. In both cases, the result consists in losing the accuracy and user is the one who supports the consequences. 7

8 LOADCELLS Special consideration for truck scales grounding If the weighing system is installed outside (in open spaces), the following preventive measures must be taken into consideration to ensure that the equipment is grounded and protected against lightning. Grounding Outdoor installed truck scales must be equipped with a grounding belt which surrounds the whole installation. This wire must be a galvanized steel flat bar with a minimum thickness of 3.5mm and 100mm 2 section. When the grounding belt is installed, a 10Ω resistor is needed to be installed also. For more informations, see the VDE 0190 standard. The foundation plates must be connected to the grounding belt. These connections are made by galvanized steel flat bar (minimum 50mm 2 ) or copper tape (minimum 10mm 2 ). The grounding schematic is applied especially for truck scales. Protection against lightning In addition, the most important element of the protection circuit against lightning is acomplishing an electrical connection between different parts of the weighing installation to equalize the electric potential. Installing a steel or copper pipe, water resistant, between the scale and the location where are placed the electronic equipments is the best solution because it provides the posibility of cable routing and ensures in the same time their protection. Is recommended that the lightning protection systems to be installed in the junction box and in the main power supply for the weighing electronics. For more informations see the exterior lightning protection guide (VDE Standard 0185, Part 1 and 2). Protection against surge voltage Type: Gas discharge tubes. Specifications: > > Nominal breakdown voltage: 90V ± 15% (at 100V/s increased voltage) > > Maximum breakdown voltage: < 800V (at 1000V/s increased voltage) Tests: > > A.C. discharging current: 10A (5 times for 1 second with 3 ms interval) > > Discharging current: > > 100A (10/100µs, 300 times with 3 minutes interval) > > 10kA (8/20µs, 10 times with 3 minutes interval) > > Isolation resistance: > MΩ > > Electrode capacity: < 2pF (at 1MHz frequency). 8

9 Scale The connection between the protection edge and the mounting plates from the reinforcement (only for concrete scales) Foundation grounding for building (The equalizing potential is connected to the building grounding system) Connection between the steel pipe and the foundation grounding The loadcell cable to the weighing digital indicator Loadcells wires Junction box Connection between the junction box body and the steel pipe Steel or copper pipe for cables routing between the scale and the building Connection between the steel pipe and the foundation grounding Foundation ground (steel flat bar of minimum 3.5mm thickness or 100mm 2 section) Connection between mounting plates and the grounding belt (galvanized steel flat bar 50mm 2 section or copper flat bar of 10mm 2 Bridge loadcells with copper wire straps for lightning protection (or installation electric interferences) Loadcells Concrete foundation 9

10 LOADCELLS GLOSSARY THE LOADCELL is an electromechanical device. More specific, is a transducer which converts an energy form into another - a mechanical force into electrical energy. A loadcell has various characteristics which can be read. These are determined by the used metal type, by the loadcell form, and by the protection level against surrounding environment. To know about the loadcells and to use them in applications you have to know related terms. CALIBRATION Comparing the output signal of the loadcell with standard weights. COMBINED ERROR (non-linearity and hysteresis) Maximum deviation from the straight line between the output corresponding signal point and the nominal output signal point, expressed in procents of the nominal output signal and measured at load increase and decrease value. CREEP Time variation of the loadcell output signal during the loading process at constant environment/other variables conditions. CREEP RECOVER Output signal variation for zero load, in time, after removing the load which has been applied for a time period. DERIVE Random output signal variations at constant load conditions. ECCENTRIC LOAD Any load applied in parallel, but not concentric, to a primary axle. ERROR Algebric difference between the displayed value and the real value of the load. EXCITATION SIGNAL The voltage applied to the input terminals of the loadcell. Most loadcells have a nominal excitation voltage of 10VDC. There are also loadcells with a nominal excitation voltage of 15, 20 and 25VDC and some of them allows both DC or AC voltage. HYSTERESIS The maximum difference between the output signal values of a loadcell measured at the same load. A measurement is made increasing the load from zero, and another one decreasing the load from the nominal value. Hysteresis is expressed in procents of the output signal for nominal load (%). The most common hysteresis values for loadcells are 0.02%, 0.03% and 0.05%. BRIDGE INPUT RESISTANCE Loadcell input resistance. Is measured with a ohmmeter at the input or excitation pins. Usually it is higher than the output resistance because of the compensation resistors from the excitation circuit. INSULATION RESISTANCE DC current resistance measured between the loadcell electric circuit and body. NONLINEARITY Maximum calibration curve deviation from the straight line between the corresponding zero load output signal point and the nominal output signal point. Is expressed as a procent from the nominal output signal. Is measured only for an increasing load. Most often values are 0.02% and 0.03%. OUTPUT SIGNAL The signal generated by the loadcell. It is directly proportional with the excitation signal and the current load. The output signal is expressed in milivolts / volt (mv/v) or volt / amper (V/A). NOMINAL OUTPUT SIGNAL Algebric difference between the zero load output signal and the nominal load output signal. ACCURACY Maximum difference between the output signal values measured repetitive for the same load in the same environment conditions. RESOLUTION Smallest change of the load value which can determine a detectable output signal change. MAXIMUM OVERLOAD Maximum overload, in procents than the 10 nominal capacity, which can be applied without making a permanent change of the loadcell performance characteristics. A common value for maximum overload is 150%. SENSIVITY The ratio between the signal variation and the load variation. SHOCK LOAD A fast increase of the load value, caused usually by a weight fall on the scale. It can damage permanently the loadcell. SIDE LOAD Any load acting perpendicular on primary axle in the load applying point. TEMPERATURE VARIATION OF NOMINAL OUTPUT SIGNAL Nominal signal variation with the environment temperature. Usually is expressed in variation procents of nominal output signal at 100 F environment variation temperature. ZERO LOAD SIGNAL AT TEMPERATURE VARIATION Zero load output signal temperature variation. Usually is expressed in procents as zero load signal variation from the nominal output signal for an environment temperature variation of 100 F. COMPENSATION TEMPERATURE DOMAIN The temperature domain in which the loadcell is compensated to maintain the nominal output signal and zero load signal values in the specified limits. LIMIT OVERLOAD The maximum load, in procents than the nominal capacity, which can be applied to the loadcell without to cause structure deformations. ZERO LOAD SIGNAL Loadcell output signal at nominal excitation and without load, usually expressed in procents of the nominal output signal.

11 SELECTION CRITERIA -30t Perfect hermetic sealing ROCKER COLUMN centering loadcells do not need constrainers Lightning protection C4 30t capacity of every loadcell ensures the best metrological performance Glass to metal + filled with nitrogen gas Gas discharge electronic tubes Accuracy class which allows 10kg division in 400kg..30t interval and switches automatically to 20kg in t interval Compression loadcells 20t or 40/50t A simple housing, hermetic sealing Does not exist GP, C o C Operating temperatures C 300% IP68/IP69K 17-4 PH Safety overload <150% >300%: 500% is an absolutely useless value Protection level: totally protected against dust and water Stainless steel which provides the best performance from all stainless steel alloys Matched Output Technology Y-Factor (Multi Range)=E Y max /v min MTBF>35 years > loadcells installed in Romania ~ Mean Time Between Failures represents the fiability loadcells installed worldwide IP67 common stainless steel Does not exist Y= Does not exist a comparable value 11

12 Experience 20 years Warranty 10 years References 1200 weighbridges Permanent stock FLINTAB WARRANTY NOVEMBER FLINTAB NEO BUSINESS CENTER 22 Carpenului Street Ploiesti, Romania Dana RUS FLINTAB Manager