Why we use End of Line (EOL) Resistor in Fire and Gas System ?
The End-of-Line Resistor used in fire alarm systems and security systems may look the same as a Terminating Resistor, however the function of the End-of-Line Resistor is completely different. It's…
Analyze the Relay Circuit and Find the Status ?
Determine the statuses of all lamps and relay coils in this circuit, given the following process conditions: Flow = 4 GPM Pressure = 24 PSI Temperature = 190 Deg F…
How Overload Heaters used to Automatically Shut the Motor OFF ?
How Overload Heaters used to Automatically Shut the Motor OFF & Prevent Damage ? Some common components of three-phase motor control circuits are shown here in the following illustrations. These…
What is a Cable Gland ?
Defining Cable Glands A device designed to permit the entry of a cable, flexible cable or insulated conductor into an enclosure, and which provides sealing and retention. It also provides…
Identify High Flow Alarm and Low Flow Alarm?
Identify which lamp in the following ladder-logic diagram is the high-flow alarm and which is the low-flow alarm.
Types of Pneumatic Valves : Poppet & Spool
Valves are essential components in every pneumatic system, providing a method by which the air flow to or from other devices can be accurately controlled. The following chapter looks at…
Alarm and Trip Systems
Alarm and Trip Systems The purpose of an alarm system is to bring a malfunction to the attention of operators and maintenance personnel, whereas the purpose of a trip system…
Pneumatic Valves and Cylinders Sizing – Part 2
Air Consumption and Air Flow The difference between air consumption and flow rate can sometimes be confusing since both are specified using the same units. Air Consumption is defined as…
Pneumatic Valves and Cylinders Sizing – Part 1
Valve and cylinder sizing represents possibly the most important element in the design and specification of any pneumatic system. Carried out correctly, it will ensure that capital and operating costs…
Instrumentation Diagrams Multiple Choice Questions
Instrumentation Diagrams Multiple Choice Questions Question 1 Identify what type of diagram this is: (A) Wiring diagram (B) Isometric drawing (C) SAMA diagram (D) P&ID (E) Loop diagram Answer :…
