Calibration and Preventative Maintenance Procedures
Calibration and Preventative Maintenance Calibration: A comparison of two instruments or measuring devices one of which is a standard of known accuracy (traceable to national standards) to detect, correlate, report…
What is a Active Barrier ?
An active barrier uses transformers, optoisolators or relays to provide isolation between the hazardous area and the non-hazardous area. It does not require an intrinsically safe ground connection. Either or…
Zener Diode Barrier Principle
The zener diode barrier works by diverting potentially dangerous energy to ground before it can reach the hazardous area. Zener Diode Barrier Principle The zener diodes limit the fault voltage…
Stepper Motors Objective Questions & Answers
Stepper Motors Objective Questions & Answers 1. A variable reluctance stepper motor is constructed of ______________ material with salient poles. a) Paramagnetic b) Ferromagnetic c) Diamagnetic d) Non-magnetic Answer: b…
Pneumatic Control Mechanisms Objective Questions
Pneumatic Control Mechanisms Objective Questions 1. With a proportional-plus-integral controller, a sustained error will result in: a. Windup b. A fixed offset c. A temporary narrowing of the proportional band…
Level and Density Measurement Objective Questions
Level and Density Measurement Objective Questions 1. An open tank contains a liquid of varying density and the level within the tank must be accurately measured. The best choice of…
Pneumatic Systems Objective Questions
Pneumatic Systems Objective Questions 1. Fluid power circuits use schematic drawings to: a) Simplify component function details b) Make it so only trained persons can understand the functions c) Make…
Conductivity Transmitter Calibration Procedure
In this article, we discuss about How calibration is to be performed through decade resistance box for a conductivity transmitter. Image courtesy : Emerson analytical Theory : Conductivity is the…
Orifice Plate Tapping – Orifice Plate Taps
Different types of Orifice plate Taps are Flange Taps, Corner Taps, Vena contracta taps. This article provides information on Orifice Tapping Location.
Motor VFD Drive features
Modern DC and AC motor drives provide features useful when using electric motors as final control elements. Some common features seen in both VSDs and VFDs are listed here: Speed…
