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Showing posts with the label Instrument

What are flange pipe fittings?

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What are flange pipe fittings? A flange pipe fitting is a fitting used to connect valves, pumps and other piping system equipment, basically these fittings are connected with the help of nuts and bolts. And flange joints are compressed by inserting donut-shaped gaskets before the bolts are tightened. A flange is an external or internal part used to connect pipes, valves and other equipment or to connect a piping system. Flange joints are mainly used on equipment joints like pipes, valves where frequent maintenance is required. A flange is a reinforcement or connection to another object, such as a flange at the end of a pipe, and flanges are used when joints need to be separated. Flange A flange is basically a metal ring that connects to a pipe or valve and other system. And usually this flange is attached to the end of the pipe and this flange has some holes to connect another flange using nut and bolt. The flange joints are pressure tightened by inserting donut-shaped gaskets before t

Instrument identification tag

Instrument identification tag AIT:  Analytical Indicator Transmitter (eg oxygen concentration analyzer with built-in display of oxygen percentage) ESL : Voltage switch, low (a switch used to detect under-voltage conditions in an electrical power system) FFI : Flow Ratio Indicator (a device that indicates the ratio between air and fuel for large industrial engines) FIC:  Flow Indicating Controller (and is a controller designed to indicate flow to a human operator) HC:  Hand controller (and is a device that allows a human operator to set a control signal to some desired level, usually to operate a valve or other final control element) JQR: Power totalizing recorder (eg watt-hour recorder, tracking total energy used) LSHH: level switch, high-high (for example, a level-sensing switch designed to detect dangerously high liquid levels and initiate an automatic shutdown in that event) LT: Level Transmitter (and is a device that detects liquid level and reports that level in some analog or dig

What is a recorder?

What is a recorder? Recorder Basically the recorder is a common auxiliary device and is used to graph the process variable. Recorders usually have indicators built into them to show the instantaneous value of the instrument signal along with historical values, and for this reason are commonly designated recorder indicators. Circular chart recorder A circular chart recorder uses a round sheet of paper, moving slowly under the pen and moving sideways by a servomechanism driven by an instrument signal. Bar chart recorder A strip chart recorder uses a scroll of paper drawn gently behind one or more side-moving pens, while a paperless recorder eliminates paper entirely by plotting graphic trend lines on a computer screen. Recorders are extremely useful for troubleshooting process control problems. This is especially true when the recorder is configured to record not only the process variable but also the setpoint and output variables of the controller.

What is Indicator and its Example

What is Indicator and its Example Indicator Essentially an indicator is a common auxiliary device and is used to provide a human readable indication of an instrument signal. And an inductor is basically a distance amplifier. Inductors are used to accurately measure small distances or angles. The indicator gives the human operator a convenient way to see what the output of the transmitter is without connecting test equipment. Furthermore, the indicators can be located away from their respective transmitters, providing a readout at a location more convenient than the location of the transmitter. Indicators are a measuring tool so they are used to indicate. And to understand what the data on the indicators actually shows, some basic understanding of elementary statistics is required. Also the ability to understand the data will help you adjust, challenge or change the indicators being used. A good indicator is a measure of an excellent system. Indicative Example Temperature Indicator The

Introduction to Industrial Measurement

Introduction to Industrial Measurement Various types of control systems and instruments are used in industry to complete the process and basically to measure and calibrate the process. Simple industrial measurements are fluid pressure, fluid flow, system or object temperature, environmental temperature, fluid volume, chemical concentration, system acceleration, device speed or position, object physical diameter and device voltage, current, resistance, etc. Fluid Pressure Measurement: This parameter measures the pressure of a fluid or object using various types of devices or sensors. And there are two types of this measurement manual measurement and automatic measurement. A common automatic gauge is used to measure fluid pressure and a differential pressure sensor is used in this measurement. Fluid Flow Rate: The this parameter measures the fluid flow throughout a pipe or object, and the this measurement uses a variety of sensors to measure fluid flow. And generally measure this parame

Some General Instrumentation Terms and Measurements

Some General Instrumentation Terms and Measurements Process The physical system we are trying to control or measure. Examples: water filtration system, molten metal casting system, steam boiler, oil refining unit, power generation unit. Process variable, or PV A specific quantity we measure in a process. Examples: pressure , level , temperature , current , electrical conductivity, pH, position, motion, vibration . Setpoint, or SP The value at which we want the process variable to be maintained. and is also known as the target value of the process variable. Primary Sensing Element, or PSE A device that directly senses a process variable and translates that sensed quantity into an analog representation (electrical voltage, current, resistance; mechanical force, velocity, etc.). Examples: thermocouple, thermistor, Borden tube, microphone, potentiometer, electrochemical cell, accelerometer. Transducer A device that converts one standardized signal to another standardized instrumentation si

Permanent Magnet Moving Coil Mechanism (PMMC)

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  Permanent Magnet Moving Coil Mechanism (PMMC)  In PMMC meter or (D’Arsonval) meter or galvanometer all are the same instrument, a  coil of fine wire is suspended in a magnetic field produced by permanent magnet. According to the fundamental law of electromagnetic force, the coil will rotate in the magnetic field when it carries an electric current by electromagnetic (EM) torque effect. A pointer which attached the movable coil will deflect according to the amount of current to be measured which applied to the coil. The (EM) torque is counterbalance by the mechanical torque of control springs attached to the movable coil also. When the torques are balanced the moving coil will stopped and its angular deflection represent the amount of electrical current to be measured against a fixed reference, called a scale. If the permanent magnet field is uniform and the spring linear, then the pointer deflection is also linear.

Analog Instruments

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  Analog Instruments Analog instruments are characterized by their continuous signals. A purely analog instrument measures, transmits, displays, and stores data in analog form. The signal processing is realized by analog components that are integrating together as functional blocks, as illustrated in Figure  Some examples of functional blocks are bridges, amplifiers, filters, oscillators, modulators, offset circuits, level converters, and buffers. Three basic components are common in all types of analog signal processing:- resistors, capacitors, and inductors. The main function of a resistor is to limit the current. The current will flow through a capacitor only if the voltage changes across it. In the case of inductors, voltage is established only as a result of a change in the current across it. Other analog components, including semiconductor devices such as diodes, transistors, operational amplifiers, and rectifiers, are based on these three basic elements. Two basic types of semic