Answer Posted / www.islamqa.com

perfect answer sam as usual

and if there is something else to say I can say that split
range control ( or call valve sequencing ) is a technique
used for satisfy the procsee requirements.

Actually we have techniques and modes for this strategy.

The used techniques to achieve valve split
ranging /sequencing are:

1 - Valve bench set adjustment (modify the valve itself)
2 - Positioner adjustment
3 - I/P adjustment
4 - Using 1 controller with 1 I/P and 2 adjusted valves
and this is very slow process as we have to wait a long
time till the pressure is built up witin the loop.
5 - using 1 controller with 2 series I/P
and here we face the risk of voltage drop.
6 - using 1 controller with dual o/p.
7 - using 2 controller with the same input.

# And we have 3 main modes for this strategy:

1 - COMPLEMENTARY:
where 1 of 2 valves opening is opposite to the other
@ 4 ma valve-A is fully open while valve-B is fully closed
and thier stems move synchronously.
2 - EXCLUSSIVE
3 - PROGRESSIVE

Ahmed Sabry
Control and Instrumentation Engineer
GPC - General Petroleum Company
ahmedsabry.online@gmail.com
CELL.: 00 2 0121367310

How can test or measure the probe and extension cable to identify if the problem at the probe or cable or at the driver it self? (pleast notify the measuring method)

2644

---

How to change dcs card in online. (Dsc is maxdna)

2820

---

any body who gone thru recent iocl interview.INSTRUMENTATION questions. I need.

2538

---

Introduce yourself which is not present in your biodata?

2485

---

What is Erosion in a control valve?

2189

---

Can u tell me the principle of the tc,rtd,level switch,pressure switch ,transmitter(pr flow level temp.),vibration...plz

2097

---

why orfice is not used for main steam flow calculation

2183

---

IS there any effect of vortex in low pressure side of the transmiter after the orific in feed water line? if yes then what is the calculation?

2447

---

How to calibrate level transmitter with use of HART?

2819

---

what is sil (safety integrity level

2787

---

List three types Level Switches with their working principles

2182

---

I have 0.75mm sq multicore cable (IS type) , can use instead of same type but 1.5 sq mm cable ? Note : The distance is around about 150 meter.

1625

---

Define cryogenic?

1223

---

all types instrumentation questions want

2235

---

how radio frequency level probes works with its controller ? what is its principle ? pls give me brief explanation?

1927

---