Capacitively Coupled Multistage Transistor Amplifier
Two or more amplifiers can be connected in a cascaded arrangement with the output of one amplifier driving the input of the next. Each amplifier in a cascaded arrangement is…
Transistor Amplifier Working Principle
A linear amplifier provides amplification of a signal without any distortion so that the output signal is an exact amplified replica of the input signal. A voltage-divider biased transistor with…
What is Field Transmitter Damping ?
The vast majority of modern field transmitters (both analog and digital) come equipped with a feature known as damping. This feature is essentially a low-pass filter function placed in-line with the…
Instrument Zero and Span Calibration
Every instrument has at least one input and one output. For a pressure sensor, the input would be some fluid pressure and the output would (most likely) be an electronic…
Field Instrument Calibration Errors
The efficient identification and correction of instrument calibration errors is an important function for instrument technicians. For some technicians – particularly those working in industries where calibration accuracy is mandated…
Bridge Rectifier Working Animation
What is Rectifier? A rectifier is a device that simply converts alternating current (AC) into direct current (DC). The way a rectifier changes AC to DC is by the use…
HART Communication Tutorial Part 1
HART, an acronym for Highway Addressable Remote Transducer, is an open process control network protocol and was introduced in the late 1980s. It is a hybrid communication protocol that uses…
HART Communication Tutorial Part 2
HART ADDRESSING HART addressing is of two types: polling address and unique identifier. Polling address is single byte and is also known as “short address.” Unique identifier is of 5 bytes…
HART Communication Tutorial Part 3
HART COMMUNICATION LAYERS The HART protocol follows the seven-layer OSI (Open Systems Interconnection) protocol, although it uses only three layers: application, data link, and physical. The other four are not…
HART Communication Tutorial Part 4
INSTALLATION AND GUIDELINES FOR HART NETWORKS HART devices use the conventional 4–20 mA current signal cable path to send the HART FSK signal. Thus, no extra communication paths are required to…
