SPECIFICATION SHEET Electronic Force Proving Instrument (For verification of uni-axial testing machine) MODEL : FS-117F

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1 Applications For calibrating Uni-axial testing machines, universal testing machines, Compression and Tensile testing machine as per IS:1878, ISO 7500 or any other international standards Suitable for metrology use as a reference standard or transfer standard. Highly suitable for test benches and fatigue test First choice for structural and material testing, Press Force monitoring Advantages of electronic force proving instruments instead of force proving ring device: Electronic force proving instruments: It consists of a force transducer (loadcell ) and a high resolution display unit. They have become the most widespread of all force measuring systems and can be used as force transferred standard also. Unlike proving ring devices, these force transducers are less sensitive to temperature, creep, extraneous loads, side loads and moments. Because of the high resolution and behaviour of the system a single system can be used to cover wide range of calibration atleast from (20 to 100) % of the range for class 0 and atleast (10 to 100)% of the range for Force proving ring device: Proving ring is a force measuring instrument whose shape changes as diameter deflects elastically under load which is used as a device for calibration of uni-axial testing machines. It consists of a steel ring with a Dial gauge mounted so as to measure the vertical deflection when the loads are applied through the threaded blocks at the top and bottom. Applied load is known from its load and deflection characteristics. For all these years, the proving rings are considered as standard of excellence for force calibration. However, they suffer from the following adverse characteristics 1. Creep- If, we maintain the same force and continue to measure the length in the dial Class 1 and class 2 as per IS 4169, with no loss of accuracy. Hence, less no. of loadcells (force transducers) can be used to cover wide range, which is economical in terms of maintenance and calibration costs. Also, the advantage is with interpolation equation the force can be calculated at any given step, whereas the proving ring devices can be used at the specific forces in which they are calibrated, unless the dial gauge used is also calibrated every time the force proving ring is calibrated. gauge having a very high resolution, we will see the length continues to change slightly. 2. Deflection measurement- when the forces are applied to the proving ring, it departs from its circular shape and becomes eggshape. The determination of the deflection of a proving ring depends on the subtraction of two large numbers, namely, the inside diameter of the proving ring and length of the Dial gauge measurement assembly. Since the difference is so small, any slight error in measuring either dimension leads to a large percentage error in the number at interest, the deflection. 3. Resolution- Any mechanical measurement system introduces errors which are difficult

2 to control or overcome. The most obvious problem is resolution, which is limited by the fitness of the Dial gauge threads and the spacing of the indicator marks. Nonrepeatability of duplicate measurements taken in the same direction depends mainly how much force is applied to the Dial gauge s screw threads, while hysteresis measurements taken at the same points from opposite directions is dependent on the preload, friction, and looseness in the plates. 4. Temperature effect- Variation in the temperature of either the steel ring or the Dial gauge assembly will cause expansion or contraction, which will result in a change in the deflection reading. Hence, proving ring is susceptible to temperature effect. Also, spring constant changes with temperature, thus change in the calibration. 5. Response to extraneous forces- The construction of a proving ring does not lend itself to the cancellation of extraneous forces such as side loads and moment loads. Any load other than a pure force through the sensitive axis of the ring, can result in an extraneous output. 6. Specially trained personnel- the proving ring requires specially trained personnel for proper operation, because of the possibility of errors introduced by creep, and it also subject to errors due to temperature and extraneous loads. Normally proving rings are calibrated in terms of divisions for specific forces and hence, he should have knowledge to convert division to unit of force or vice versa. Features The shear web design yields high performance and offers high resistance to extraneous forces such as bending, side and torsional loads. Low deflection, high accuracy and lowest creep. Compact low profile design frees up valuable vertical testing space Calibrated directly with Dead weight calibration machine Temperature compensated Universal (Compression & Tension) or only Compression models available Digital TFT display of force upto 2 lakh counts depending on the capacity of the force transducer to have high resolution Microprocessor based unit with easy menu navigation having trace and peak hold mode Specification Force transducer (Loadcell): Model FS-117F RATED CAPACITIES: Only Tension or Only Compression or Compression & Tension- 1 kn, 2 kn, 5 kn, 10 kn, 20 kn, 50 kn, 100 kn, 200 kn. Only Compression- 500 kn, 1000 kn, 2000 kn ACCURACY (MAX ERRORS):

3 Characteristics of force proving instruments Class 00 of ISO 376:2011 optional Class 0 of IS: or Class 0.5 of ISO 376:2011 Class 1 of IS: or ISO 376:2011 Reproducibility 0.05% 0.1% 0.2% Repeatability 0.025% 0.05% 0.1% Error of interpolation ± 0.025% ± 0.05% ± 0.1% Hysteresis 0.07% 0.15% 0.3% Creep ( in 30 minutes) 0.025% 0.05% 0.1% Zero Return ± 0.012% ± 0.025% ± 0.05% Compensated Temperature Range: -10 C to + 40 C Operating Temperature Range: -20 C to + 60 C ELECTRICAL Rated output (Sensitivity): 2mV/V ±10% of rated output, Zero Balance: ± 2% of rated output Bridge resistance: 350 to 2100 Ohms- nominal depending on capacity MECHANICAL Safe Overload: 150% of rated output Safe side Load: 30% of rated output Ultimate overload: 300% of rated output Cable length: 2 Metres Deflection: 0.4 mm at rated capacity Handheld Digital Display unit to choose: Basic Advanced ENVIRONMENTAL Effect of temperature on output: ± 0.005% of rated output/ C Effect of temperature on zero: ± 0.005% of rated output / C Recommended Excitation Voltage: 10 Volts D.C Maximum Excitation Voltage: 15 Volts D.C Insulation Resistance:1000 Mega ohms or more Maximum Excitation Voltage: 15 Volts D.C Material, Finish & construction: i) Alloy steel, Electro less plated ii)below 5 kn Aluminium construction, anodised. Environmental Protection. IP 50 DLC-B1 (Digital loadcell with Builit-in display unit) Sample Specification of Handheld Display unit(advanced): Range of Force transducer in kn Display resolution in kn 0.1 to to to 5 1 to 10 2 to 20 5 to to to to to to Display 2.8 colour TFT to indicate applied force, unit of measurement and

4 Battery level indication Indication of direction of force: Tension : nil, Compression: ve sign Unit selection: N, kn, lbf and kgf Measurement of force in trace & peak hold mode Channel selection: Upto 4 loadcells can be calibrated to use one at a time. Data storage: nil Calibration: Easy calibration Options Available Sampling rate: 5 Hz Built-in battery: 7.2 V Li rechargeable batteries PC interface: USB port AC to DC adopter: VAC to 7.4 VDC,120 ma Operating Temperature: +10 C to +55 C Storage Temperature: +10 C to +60 C Construction: Rugged Aluminium casing Facility to store upto 1lakh test data, each data consisting of one set of test values with date and time stamp. USB Pendrive Storage Facility to recall each test values Specification of Digital loadcell with built-in Display unit: Model DLC-B1 Range and specifications of force transducer: same as above Model FS-117F. Range and display resolution same as DU-HH-102 Display: miniature character display unit with facility to plug into the Loadcell Unit of measurement: kn only, other units optional Built-in battery: 7.4 V rechargeable AC to DC adopter: VAC to 7.4 VDC, 120 ma Operating Temperature: +10 C to +55 C Storage Temperature: +10 C to +60 C

5 Calibration Report (Optional) NABL accredited laboratory calibration certificate traceable to National/International standards for Force transducer with display unit in compression, Tension or in both Note In view of continuous improvement in Design and performance, specifications are subject to change without notice.

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