Answer / senthil ramanujam mohan

I can give you simple example:-

Consider a temperature controller(on/off valve),
setpoint - 100deg
Offset - (-4)
dead band - 2
ERROR - SETPOINT - ACTUAL VALUE

If temperature raises from 90deg>>>>94>>at >96degrees the
valve closes.this is becoz we have an OFFSET of (-4
degrees)(setpoint - offset value)
So,now the valve is closed.temperature drops down from
96degrees<<95<< at 94degrees the valve starts open.this is
becoz we have a DEADBAND of 2degrees.

Error(contrl valve):-
setpoint - 100degree and actual value - 90degrees.
temp range - ( 0 to 200)for error scaling(becoz
controller works from 0 to 100%)
error scaling = 100/200 - 0.2 which is multiplying
factor for error to the controller
Finally,
ERROR = [ SETPOINT - ACTUAL VALUE ] X ERROR SCALING.
[ 100 - 90 ] X 0.2
[ 10 ] X 0.2
2.

hope you guys understand.

why we take 4 to 20 mA as out put of every instrument like pressure transmittre ?why we cant take 0 to 20mA as output?

6 Answers   OGDCL,

---

In dcs panel we are using diff type of modules ?what is module ? what is the use of modules ?diff type of module?

0 Answers  

---

what are the basic instructions used in simatic s7-300 plc?

5 Answers   Dr Reddys, HZL, Siemens,

---

How many input(Analog and digital) and outputs(Analog and digital) are there in DELTA v DCS Version 7.0?

2 Answers  

---

sir, i preparing hpcl,ongc,barc,hal exams(instrumentation engg)pls send a placement papers

2 Answers   BARC,

---

hi,i am doing 3 year in electronic and instrumentation engineering. what type of aptitude questions will be asked in a core industries and how can i improve my skills in instrumentation?

0 Answers  

---

what are level of automation & how these are distinguished ?

3 Answers  

---

what is the vital subject for scoring bhel exam&what is the question pattern

0 Answers   Bhel,

---

what will the sending unit in the fuel gauge utilizes?

0 Answers  

---

Sitrans LR460 Radar level transmitter getting level out or disturbed level during moisture present in the material ie coal in the pccb bunker in CHP.Any suggestions for this problem...????

1 Answers   ABG Shipyard,

---

Why humidity limit is 30 to 55 % for raw material storage?

1 Answers  

---

how can i calibrate E & h make conductivity transmiter . unit : mocro siemens Range :0 to 100 micro siemens sensor : capacitive type

1 Answers  

---