Precision double ended shear beam ball cup type load cell with single ball in center of load cell and cup on top of ball. Each load cell shall rated for diffrent capacity for having dynamic response characteristics and shall be employed to sense the load applied on the weighbridge platform by the laden / Unladen lorry. It shall be ruggedly constructed of special alloy tool steel to provide maximum resistance to shock and overload and overload. The stresses developed in each transducer shall be sensed by the foil type strain gauges. The ultimate overload capacity of the load cells shall assure sufficiently high overload capacity for the system. The load cells shall be totally sealed to work even under hostile environment, without any degradation in performance with special materials and constructional design features. The temperature effects for sensitivity and linearity shall be maintained low over a wide range. Further, the load cells shall be well shielded that its output is not influenced by stray magnetic fields in vicinity.
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Type center loading DOUBLE ENDED SHEAR beam cup ball load cell |
| Mode |
IPT |
10/20/30/40/50 Ton |
| Make |
P.T. |
ZEMIC (USA) |
| Rated Load |
|
30 Ton |
| Safe Over Load |
150% |
150% Of Rated Capacity |
| Ultimate Over Load |
300% |
300% Of Rated Capacity |
| Excitation |
|
5-12 V(DC) Max 18 V(DC) |
| Temperature Compensated |
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(-) 35-60 C |
| Temperature Operating |
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+10 to 40'c , -35- + 65 'c |
| Combined Error |
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0.02% FSO |
| Non Linearity |
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<+/-0.017% FSO |
| Non ROepeatability |
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+/-0.02% FSO |
| Hysterisis |
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0.02% FSO |
| Creep (after 30 min) |
|
0.02 |
| Side Load |
|
--NA-- |
| Bridge Resistancel |
|
/P-700 +/- ohms |
| O/P |
|
-700 +/- 7 ohms |
| Insulation Resistance |
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>5000 (50 VDC) |
| Integral Cable |
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12 Mtr. |
| ACCURACY CLASSOIML |
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R60 - C3 |
| MocAlley Steel |
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| Protection Class |
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IP-68 |
| Cable space4-wire shielded cable |
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| Wear and tearLesser |
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| Protection @ Impact LoadHigher |
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| Benefit Comparision These load cells shoulds be capable of taking load of any direction as depicted below And free motion to W/B. |
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| ADVANTAGE OF DOUBLE ENDED SHEAR BEAM CONCEPT IN LOADCELL DESIGN. |
| Double-ended shear beam ball in cup concept in load cell design provides the following advantages over the conventional compression type load cells. |
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Greater adverse load capability. |
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Lower sensitivity to adverse loads. |
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Lower height. |
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Lower creep and faster return to zero after load removal. |
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Higher tolerance and environmental protection. |
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Better sealing and environmental protection. |
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Freedom from barometric effect. |
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Greater flexibility of application. |
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The above advantages make the double-ended shear beam load cells superior over the conventional compression load cells and are more popular now a days in developed countries for various fields applications. A brief explanation on the above advantages is given below and the literature provided speaks in detail about the design concept, performance and applications of double-ended shear beam load cells. |
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| GREATER ADVERSE LOAD CAPABILITY |
The double-ended shear beam load cells can withstand 100% side load while fully loaded in the vertical direction. Large eccentric loads can be tolerated without any damage whereas; the compression type load cells cannot without any eccentric or side loads. |
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| LOWER SENSITIVITY TO ADVERSE LOADS |
Double ended shear beam load cells are inherently insensitive to eccentric loads, bending stresses, effects of torque and side loads whereas, the compression type of shear beam load cells eccentric load sensitivity is less than +/- 0.03% per 1/8” eccentric in the longitudinal direction and is less than +/- 0.02% per 1/8” eccentricity in the transverse direction. Also, side load sensitivity of double ended shear beam load cells is approximately ten times better than that of conventional designs. |
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| LOWER HEIGHT |
Double-ended shear beam load cells are lower in height when compared to compression type load cells of same capacity. This results in a more stable structure. |
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| LOWER CREEP AND FASTER RETURN TO ZERO AFTER LOAD REMOVAL |
By suitable selection to strain gauges in double ended shear beam loadcells the creep level is kept as low as +/- 0.025% for 20 minutes loading and zero return within +/- 0.02% in 15 seconds after load removal. It is difficult to achieve the above values in compression type loadcells. |
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| HIGHER TOLERANCE OF DYNAMIC FORCES AND VIBRATIONS |
The transducers experience high dynamic forces and vibrations during its operations. The transducer design must be such that it must withstand the above conditions without damaging the very fine solder joints connecting the different elements in the load cell. |
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| FREEDOM FROM BAROMETRIC EFFECT |
Unlike the compression load cells, double-ended shear beam load cells are free from barometric effect. In compression type load cells due to pressure difference between the cell enclosure and atmosphere, certain amount of strain will be experienced by the spring element. This needs to be compensated when the barometric effect is noticeably high whereas, in shear beam design both sides of the load cells experience the same pressure and hence the barometric effect is negligible. |
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| GREATER FLEXIBILITY OF APPLICATIONS |
Varieties of mounting technique and adapters provides shear beam load cells easily adaptable to any type of applications. |
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