Thermocouple Experiment Module is intended to study the behavior of a TC for different temperature zones. The scope of this equipment is restricted to study the temperature profile, and characteristic behavior of a J-type thermocouple. The experiment module is supplied with a thermocouple along with necessary electronics, excluding the power supply. Electronic Design Experimenter Model EDE-1 has Specifications:
This trainer makes use of an RTD (PT-100), type thermocouple. Using this thefollowing measurements can be experimented.
a) Measure resistance of thermocouple for different temperatures. b) Indicate temperature on digital indicator. c) Provision to measure either actual temperature and amplified voltage. d) Separate terminals are provided for connecting data acquisition trainer. e) Provision for automatic switch ON or OFF, once preset temperature is crossed.
Specifications:
This Trainer makes use of AD-590 Semiconductor Transducer, for measurement. The trainer consists of a heat bar with provision for inserting four AD-590 Transducers. Only one transducer is supplied with the trainer. A built-in heater heats this heat bar. Using this trainer, AD-590 temperature characteristics can be studied.
Strain Gauge is a passive transducer. This is used to measure the lateral strain exerted on a given surface. This sensor converts a mechanical displacement into a change in resistance. Positioning and quality of bonding the sensor on the surface, largely determines the accuracy. An optional external Whetstone's bridge is used to measure bridge imbalance, which is a measure of strain. A bridge is symmetrical, four-element, circuit that enhances the instrument's ability to detect small changes in the sensor. Four Strain gauge sensors arranged in the bridge configuration, balances out fixed or quiescent voltage drop, allowing magnification of the different signal. This acquired signal is conditioned and computed to indicate actual strain suffered by the surface.
In the Strain gauge experimental module, the sensor is bonded on one end of a long rectangular stainless steel metal strip of uniform cross section. This end is fixed firmly to a metallic stand. The other end is freely suspended, similar to a Cantilever. To this free end, weights ranging from 50gms to 1000 gms in multiples of 50 gms are added to create strain (elongation) on the strain gauge strip. A relation between applied stress and measured strain gives the change in resistance of the gauge, explaining the principle of strain gauge transducer. This consists of a built-in power supply, interface electronics, assorted weights. A standard digital multimeter in 2V DC range is used to make voltage measurement. This voltage measurement directly indicates the weights added on the strain gauge pan.
Cantilever Beam consists of stainless steel beam fitted with strain gauge elements and displacement transducer. Load is applied by adding weights in the weighing pan, for different load conditions, the Young's modulus can be computed. Strain gauges, and displacement transducers, are two different elements used in this trainer. Four strain gauges are employed in bridge form to measure strain.
The stress component is given by the displacement transducer. By using these two inputs, Young's modulus can be computed by arithmetic. The arithmetic is to be programmed by you in the form of a program, using Computer Applications Trainer, Model DAS-1 or Microprocessor trainer Model MPT-85, with stress and strain components as input parameters. This demonstration module provides an academic exercise to see how simple cantilever measurements can be performed for different load conditions. This interface provides an experimental setup to study how an application oriented instrument works.
a) Strain Gauge Transducer:
b) Displacement Transducer:
Linearly Variable Differential Transformer (or transducer) is a displacement transducer. This transducer converts mechanical displacement to proportional electric voltage. This experiment is primarily conducted to study the linearity of the transducer for a given displacement in it's operating range. The trainer is provided with a displacement (10mm) transducer. This transducer has a primary wind in and two similar secondary windings. The primary is connected to a SINE wave generator operating at 4Khz. Peak to peak output voltage is approximately 1V AC. Depending on the displacement, a mechanical core moves inside the transducer, permitting linkage of flux lines to it's secondary windings.
An output is available on both secondary windings, depending on the position of the core inside the transducer. A signal conditioner, instrumentation amplifier, gain amplifier, allows a proportional output at its terminals. To study the actual displacement in terms of millimeter, a micrometer jig is supplied. A plot between displacement Vs output is plotted to determine the linearity of the transducer. The same experimental module can also be used with data acquisition instrument to experiment on Data Acquisition techniques.
This trainer consists of a 1Kilo Ohm linearly variable resistor. This is connected to a voltage source. The output voltage is proportional to the displacement of this resistor's movable arm. The movable arm is connected to a micrometer jig. The displacement is measured in terms of mm. A plot between the displacement and the voltage exhibits the linear relationship. The trainer consists of the LVRT transducer, micrometer jig, and built-in power supply.
Capacitance exists between two parallel plates, when separated by a dielectric medium. The extent of capacitance depends on the common area subtended by these two parallel plates, separated by the dielectric. This principle is made use to create a variable area capacitor. The variable area capacitor is very widely used in oscillators to change the frequency of oscillations, in association with a RC network.
In this trainer, a variable area capacitor in the range of 50pf to 500pf is used to produce oscillations. These oscillations are converted to voltage. This voltage is measured on output terminals. A plot between the output voltage and the angle subtended by the transducer is plotted. An external power supply of ±12V and +5V are required.
