Question { 4439 }

there is one orifice plate already installed on 3" line, but
my previous engineer(who is not working here) removed that
tx, but now i want to take it in to the process, so now what
i have to do now? flow fluid is hytherm oil of temp. 260deg
& pressure is 3bar.

Answer

Dear Nitin,

Ideally you shall have all the records, but in case if you do not have the records then try to recalculate the DP value using orifice sizing. You can get data for process condition from your process engineer and B (beta value / bore i.d. from orifice plate itself).

If you do not know how to calculate DP the please forward all the process condition with Line size, Line schedule and B beta value to anadkat.jigar@gmail.com. I can recalculate it for you.

Hope this will help you out.

Best Regards,
Jigar Anadkat
anadkat.jigar@gmail.com

Question { Voltech, 13930 }

radial & axial vibration sensor output voltage is ac or dc volt?

Answer

Radial Vibration: AC rms
Axial Thrust : DC voltage

Question { Chevron, 11198 }

suppose in dcs range of a flow transmitter is 10t/hr what
is dp for 50% in 2500mmwc

Answer

625 mmwc

Question { ABB, 23525 }

yogokowa field bus system transmitter all's we are geting
IOP fault in Contiunes please help me fine how we can
normal the broblems?

Answer

1) Infield bus system, IOP detection is different from HART system.
2) IOP will occur only for input e.g. transmitters.
3) One probability is there (which is most common) that your transmitter is under-ranged or PV value fluctuates highly (on wither ends). Being s digital system you will not receive IOP(-) in FF system.
4) Check for alarms and run integrity test (via PRM) and check if any of the internal blocks like AI or Transducer block or Resource Block is going to OOS (Out of service or Manual Mode).
5) Additional Check :

Check if you are receiving CNF error. If it comes then you may reset the transmitter by removing the power or isolating it from Loop.
This shall resolve the error. If not then you need to replace the transmitter.

Hope this helps.

Question { 2071 }

What do you do as a Engineering person EPC for
Sizing&Selecting Control Valve?

Answer

Prepare AVL (Approved vendor list)

You need provide basic design data which includes but not limited to Temp., Pressure, Min., Max and no0rmal operating flow. Other requirement viz., Hand-wheel requirement, Max. opening time, limit switches SOV, available air pressure @ site, Noise requirement (< 85 dB) leakage class, You need spring return actuator or double acting ? what is the service (corrosive, Slurry, Liquid, Gas ) positioner requirement , booster etc. etc. and primary calculated CV.


Perform offer / bid evaluation.

Vendor meeting if required.

Provide inspection schedule , Delivery schedule. Preform factory inspection and sometimes site installation (based on company requirement) and inspection.

Question { Chevron, 2145 }

How to calibrate vertex flow meter?
How to calibrate mass flow meter?

Answer

Vortex:

Practically it is a volumeteric flow measuring device and it is not possible to calibrate online in field in most of the cases (Provide you have a proper bypass arrangement and proovers in place) , hence it is to be sent to calibration LAB where it will be compared with MASTER meter.

This MASTER meter must have superior accuracy than UUC (Unit Under Calibration).
Usually the large volume flow is tough to establish at calibration LAB hence Gravymeteric method is used in which water is passed through UUC and compared with high accuracy Load-cell. Since water density is known and constant, volume flow is calculated and new K-factor of meter is calculated.

Mass-flowmeter / Coriolis meter : Same Above mentioned Gravymeteric method is used.

Hope this will help ..!!!

Jigar Anadkat

Question { BW Instrumentation Electrical, 3258 }

How do understand by hart protocol?

Answer

HART : Highway Addressable Remote Transducer

This is a communication protocol in which all information related to transmitter / instrument travels in the same pair of power loop of transmitter.

This information is transmitted by superimposing HART signal (AC) on 4-20mA DC signal. Hence HART DC value remains zero and it will not impact 4-20mA measurement.

The digital HART information is transmitted by two different signal 1200 Hz (Represented as 1) and 2200 Hz(Represents 0) in digital system.

Since transmitter are Highway Addressable, it is possible to configure transmitter remotely through a management system (e.g. AMS or PRM).

Hope this will help.

Regards,
Jigar Anadkat

Question { BW Instrumentation Electrical, 3258 }

How do understand by hart protocol?

Answer

What Do you understand by HART protocol :

HART : Highway Addressable Remote Transducer

This is a communication protocol in which all information related to transmitter / instrument travels in the same pair of power loop of transmitter.

This information is transmitted by superimposing HART signal (AC) on 4-20mA DC signal. Hence HART DC value remains zero and it will not impact 4-20mA measurement.

The digital HART information is transmitted by two different signal 1200 Hz (Represented as 1) and 2200 Hz(Represents 0) in digital system.

Since transmitter are Highway Addressable, it is possible to configure transmitter remotely through a management system (e.g. AMS or PRM).

Hope this will help.

Regards,
Jigar Anadkat

Question { BW Instrumentation Electrical, 3258 }

How do understand by hart protocol?

Answer

HART : Highway Addressable Remote Transducer

This is a communication protocol in which all information related to transmitter / instrument travels in the same pair of power loop of transmitter.

This information is transmitted by superimposing HART signal (AC) on 4-20mA DC signal. Hence HART DC value remains zero and it will not impact 4-20mA measurement.

The digital HART information is transmitted by two different signal 1200 Hz (Represented as 1) and 2200 Hz(Represents 0) in digital system.

Since transmitter are Highway Addressable, it is possible to configure transmitter remotely through a management system (e.g. AMS or PRM).

Hope this will help

Regards,
Jigar Anadkat

Question { Atul, 29694 }

What is the difference between instrument earthing and normal earthing? and why is it necessary to do so?

Answer

Dear Shashank,

There are mainly three types of earthing used in instrumentation.
1) Power earth
2) Signal / Instrument Earth
3) IS Earth

Power earth :
Provides ground reference to all power cables. Usual practice to have MAX . Earthing resistance ~ 100 Ohms (There is no harm if it is lower)

Signal / Instrument Earth :
Provides ground reference to all Signal cables (including ICS systems).
Usual practice to have MAX . Earthing resistance ~ 10 Ohms (There is no harm if it is lower)

3) IS Earth (Intrinsically Safe Earth) :
Provide ground reference for all IS signals. MUST NOT EXCEED 1 OHM.

You can have multiple earthing pits of same kind of earth and can be connected in parallel in order to reduce the over all resistance.

Question { Shyam Steel, 2067 }

We have yokogawa cs3000 one fcs and 4 his. After download to his, showing successfully at es, but not transferred to his.

Answer

Dear,

First of all question is not clear that you are downloading what ? presume that you are downloading Graphics as other configuration will be downloaded to FCS and then automatically it will be "Equalized" to all HIS.

When you download any graphic in Engineering work station, the particular graphic will not appear in HIS unless you have pasted same graphics shortcut to any HIS. So, you can follow this procedure :

1) PASTE shortcut in respective HIS.
2) Once you download the required graphic in Engineering workstation the close the builder and select the particular graphic and in TOOLS MENU select the option DOWNLOAD TO HIS.

By this your graphic will be EQUALIZED in all HIS where you have pasted the shortcut of that graphic.

Fell free to post your result or any further question on :

Jigar Anadkat
E-mail : anadkat.jigar@gmail.com

Question { 2638 }

I have a problem with a valve (air to close).
When it is fully closed and try to open 1% it doesn't responce till 3% open suddenly more than 3% then back to 3%.
I tried to tune positioner then removed it, the problem still exist.
Any idea

Answer

There can be may issues :

1) Very first indication is that your plug and seat are having some foreign particles or uneven surface which is restricting the valve for initial opening.
2) Check the springs of the actuator for any crack as when pressure is increased it lifts the valve.
3) Check for positioner relay.

Question { WB, 1901 }

pt range is -45 psi to 45 psi.friends can you give answer with calculation and with linerity scale like 0%,25%,50%,75%& 100%?

Answer

0 % = (-45) PSI = 4 mA
25%= (-22.5) PSI= 8 mA
50%= 0 PSI = 12 mA
75%=22.5 PSI = 16 mA
100% 45 PSI = 20 mA

Calculation :
LRV = (-45) PSI
URV = 45 PSI
SPAN = URV - LRV = 45-(-45) = 90
Calculate % of SPAN for e.g. 0 PSI is {(0-(-45))/SPAN}*100 = (45/90)*100 = 50% of SPAN
mA= [{(% of SPAN)/100}*16]+4 or in other terms ...
1% of SPAN = 4+0.16 = 4.16 mA
2% of SPAN = 4+0.32 = 4.32 mA
3% of SPAN = 4+0.48 = 4.48 mA
.
.
.
.
50% of SPAN = 4 + 8 = 12 mA
.
.
.
100% of SPAN = 4 + 16 = 20 mA


Hope this will be helpful to you.

Best Regards,
Jigar Anadkat
anadkat.jigar@gmail.com