PLC: Programable Logic Controller What is a Programmable Logic Controller (PLC)? A Programmable Logic Controller ( PLC ) is an industrial control device used to monitor and control mechanical instruments or processes using different types of input and output signals. It functions as an industrial computer designed for reliable operation in harsh environments. A PLC works with four main types of signals : DI (Digital Input): Receives ON/OFF signals from sensors or switches. DO (Digital Output): Sends ON/OFF control signals to actuators or relays. AI (Analog Input): Receives continuous signals (e.g., temperature, pressure, level) from transmitters. AO (Analog Output): Sends continuous control signals (e.g., 4–20 mA) to control devices such as valves or drives. PLCs are programmable , meaning their operation can be customized using a programming language to control various processes and instruments. The most commonly used PLC programming language is Ladder Lo...

What is a Temperature Transmitter? A Temperature Transmitter is a device that converts the signal from a temperature sensor (such as a Thermocouple, RTD , or PT100 ) into a standard analog output signal, typically 4–20 mA. The transmitter processes the input from the connected temperature sensor and transmits a corresponding current signal based on the measured temperature. The output range (4–20 mA) represents the full scale of the sensor’s temperature range, which can be configured as per the required measurement range.  And this signal connected PID controller, PLC & DCS . Key Functions of a Temperature Transmitter 1. Signal Conversion and Amplification The Temperature Transmitter converts the signal from a temperature sensor (e.g., Thermocouple, RTD, PT100) into a standard output signal such as 4–20 mA, 0–10 V, or digital (HART/Modbus) formats. It also amplifies the low-level sensor signal to ensure accurate and stable transmission over long distances. 2. Diagnostics Mod...

What are Clamp-On Ammeters? Clamp-on ammeters are basically a device used to measure current. It has a jaw-type holder that can be opened or closed like a hand jaw to hold the conductor around. The jaw contains an internal current transformer. It measures current in a circuit by measuring the strength of the magnetic field around the conductor.

What is a Gas Filled Dial Thermometer? Essentially, the gas-filled dial thermometer is a measuring principle based on the volumetric temperature expansion of the gas filling in the measuring element. The measuring element is tightly connected by a capillary tube containing a measuring spring. The spring transfers the expansion of the gas filling through the movement on the dial. Gas-filled dial thermometers are used for temperatures ranging from -80°C to +600°C. The accuracy is ± 1% of full scale deflection. A gas-filled dial thermometer can be supplied with a capillary line between the measuring element and a 100 m long spring.

What is a Bimetallic Dial Thermometer? A bimetallic dial thermometer is basically a measuring element that consists of two, metal tapes, joined together. Tapes with different thermal expansion coefficients. The coiled measuring element is fixed at the end of the stem; The other side is attached to a pointer axle. Temperature changes cause the bi-metal to stretch or bend, causing the coiled component to twist. This movement is proportional to the temperature change and is shown on the dial. Bi-metal dial thermometers are used for temperatures ranging from – 50°C to +500 C. The accuracy is ± 1,6% of full scale deflection.

What is an absolute pressure gauge with a diaphragm? Basically, an absolute pressure gauge with a diaphragm in this type of gauge is used to measure pressure, independent of any changes in ambient pressure. The pressure chamber shall be isolated by a thin diaphragm. A chamber that will not be loaded to gauge pressure, will be evacuated to absolute vacuum. This vacuum (= absolute zero-point) is called the reference pressure. The diaphragm will be loaded with measuring pressure and will flexibly deviate from its normal position, thus transmitting the pressure through the bellows upon movement. Absolute pressure gauges are used for measuring gases and liquids; It can be aggressive too. The accuracy is ± 1,6% of full scale deflection. Basically, an absolute pressure gauge with a diaphragm in this type of gauge is used to measure pressure, independent of any changes in ambient pressure. The pressure chamber shall be isolated by a thin diaphragm. A chamber that will not be loaded to gauge pr...

What is Differential Pressure Gauge? Basically, differential pressure means that the pressure chamber will be separated by a thin diaphragm. This diaphragm is under constant pressure from both chambers and additionally has a gauge pressure from one chamber. The diaphragm will transmit pressure differences through the bellows on movement. The movement shows a positive or negative value on the dial with a 270° angle. The bellows on the opposite side compensates the force. Differential pressure gauges are used for measuring gases and liquids; It can be aggressive too. The accuracy is ± 1,6% of full scale deflection. The ambient temperature should be from -20 to +60 °C; and medium temperature not exceeding +100°C.

What is chemically sealed Bourdon tube pressure gauge? Basically Borden tube gauge will be fixed on the seal. A seal consists of a defined cavity that is closed off with a thin, flexible diaphragm. The volume between this diaphragm and the Borden tube will be filled with transmission fluid after it has been completely emptied. When pressure is applied, a flexible diaphragm will use this fluid to transmit the applied pressure, thus lifting the gauge. A Borden tube transfers the measured pressure using movement on a dial with a 270° angle. As the liquid fills, the connection between the seal and the gauge should remain closed. The seal can be made in various forms and types. The gauges with seals can be used to measure pressure from -1 bar to 1000 bar. The accuracy is ± 1,0% of full scale deflection. Sealed gauges are mainly used outdoors as there is no risk of freezing. The gauge with connecting flange is suitable for highly viscous, crystalline and medium solid materials. Flat seals ma...

What is a capsule pressure gauge? Basically the capsule consists of two thin, concentrically corrugated diaphragms welded or attached together. The pressure change in the capsule causes elastic deformation on both sides of the measuring element. The travel of the measuring element is proportional to the pressure being measured. It will be transmitted to a pointer using a geared movement and indicated on a dial with a 270° angle. Capsule pressure gauges are used for measuring low positive or negative values up to 600 mbar. The accuracy is ± 1,6% of full scale deflection. Capsule is made of Brass or SS316. and is only used to measure gases. And this ambient temperature will be -20 +60 °C; The medium temperature shall not exceed +100°C.

What is a diaphragm pressure gauge? Basically a diaphragm pressure gauge, the concentrically corrugated diaphragm would be fixed between two flanges. The diaphragm will be loaded by the process pressure on one side and will flexibly deviate from its normal position. This path is proportional to the pressure applied and will be transmitted in a rotary geared movement. The movement has a pointer and shows pressure on the dial with a 270 angle. Diaphragm pressure gauges are used to measure the pressure of gases, vapors and liquids from 40 bar and vacuum to -1 bar. The accuracy is ± 1,6% of full scale deflection. Tantalum, Hastelloy C etc. Or the diaphragm can be protected from aggressive media by using a PTFE-coated foil. The connecting part can be made or protected with suitable materials, ie SS 316L, PP, PVC, PVDF etc. Diaphragm pressure gauges with open measuring flanges are perfectly suited for media containing highly viscous, crystalline and solid substances. Diaphragm pressure gauge...

What is Bourdon tube pressure gauge? Basically Bourdon tube pressure gauges will have flexible (circular) measuring elements soldered or welded into sockets; The free end is closed tightly. The change in pressure causes the deflection of the measuring element. This deflection of the free end of the Borden tube is proportional to the applied pressure and is transmitted in a rotary geared movement. This movement carries a pointer and indicates pressure on the dial with a 270° angle. Bourdon tube gauges are used to measure high pressures up to 1000 bar and vacuums of gases, vapors and liquids down to -1 bar. The accuracy is between ± 0,1% and ± 2,5% of full scale deflection. In case of aggressive media, Borden tube can be made of brass, stainless steel or Monel.

How many types of pressure gauge are there? Basically the types of pressure gauges are Bourdon tube pressure gauge, diaphragm pressure gauge, capsule pressure gauge, Bourdon tube pressure gauge with chemical seal, differential pressure gauge, absolute pressure gauge with diaphragm.

What is a Voltage Reference? Essentially voltage references are electronic components, devices or circuits that are designed to provide a constant DC (direct current) output value or constant voltage, regardless of variations in other external variables. These may include total device load, power supply variations, temperature, humidity, elapsed time, and a variety of other variables. And the types of voltage references are shunt voltage reference, series voltage reference, bandgap voltage reference.

What is Instrument Cable? Basically instrument cable is used for automation and instrumentation control. Instrument cables are thin in size and can handle only a small amount of voltage and current (typically up to 24VDC and 20 mA). All instruments, field devices and controllers like PLCs require this type of cable to control the current.

What is a power cable? Power cable is basically used for high voltage transmission. Power cables are used to handle high voltages and currents (typically up to 400 A and 32KVAC).