Controller not working in auto mode?...what are the problem can occur...Pls explain
Question:
Controller not working in auto mode?...what are the problem can occur...Pls explain
Answer:
If a controller is not in automatic mode it is either broken or in manual mode.
In manual mode the controller's output is fixed at some percentage output and the controller is not adjusting its output to maintain the setpoint (SP).
While running at a fixed output, the process's process variable (PV) will generally stabilize at some value above or below the setpoint. PV changes will be dependent on external influences, like load changes.
However, if the output reaches an extreme, like 100% or 0%, the process can be put in jeopardy of going into a hazardous state from the uncontrolled input into the process or removal from the process of energy or mass, whatever the controller is controlling. Presumably, safeties are in place to shutdown the process should those dangerous conditions result from manual mode.
Carl Ellis
Measure First
Is This Answer Correct ? | 4 Yes | 0 No |
Control valve Flow characteristic. How the equal percentege curve form?
what is the standard of determining opening/closing time of Motor Operated Valve?
why k factor is important to know in flow transmitter. if we don,t know k factor what will be issue we can face .
1 Answers Flour Tech Engineers (P) Ltd,
Tell me about the synchronization panel.
WHAT ARE MAIN DIFFERENCE BETWEEN DCS AND SCADA?
7 Answers ABB, Gold Fields, Rand Water,
what does mean by analog output trim and where this one used for?
why we are using drum level control valve air to close?
how u calibrate sox nox co2 co in cemps?what is opacity n HPm?tell the standard parameters of cems?
How vortex sensor used for steam flow measurment can be checked on line i.e without taking out from process line.
What is the difference between HMI and MMI?
How is automatic reference junction compensation carried out in temperature recorders?
how many type of control valve?