Answer / sam

The internal screen is always floating at the instrument.
This means we just put some heat shrink on it to seal it and
then tie it off inside the instrument and just let it lie
there. The overall screen (braiding surrounding the cable
just below the pvc outside)will be in contact with the gland
once you have installed the gland. On the gland thread you
install a copper gland ring and a red IP washer, and the
gland then are attached to the instrument. From the gland
ring you use a six mm bolt and nut with copper washers to
attached a small diameter earth wire (about 4 to 6mm is
fine). This earth wire is then attached to the outside of
the instrument at the earth connection point on it's
housing. Every instrument will have this earth connector on
the outside of it's housing. From there you attached another
earth wire to the earth boss nearby. This boss is normally
just a piece of round bar about 40mm in diameter and about
30mm long and tapped in the middle that is welded to the
structure close by, specially for this earthing of the
instruments. Again it is better to use copper washers. If no
boss is available you can use some other point on the
structure as well like a stainless steel cable tray for
instance but the earth boss should really be part of the design.
On the other side of the instrument cable at the RTU the
internal screen in attached the instrumentation clean earth.
The dirty earth is used only for electrical equipment.
Good luck

Why DP transmitters are subjected to high static pressure test of 100 bar. Though they will be used for very small pressure range

4 Answers   HPCL,

---

how does we calibrate a square root flow transmitter ,give an example and explain it step by step like range calculation , calibration hook up series connection , zero check , and how to apply pressure , and if not geting proportional output then what should we do ?

0 Answers  

---

How to gennerate earth leakage monitoring alarm for solenoid valves in control system?

2 Answers  

---

what is the difference between hub and switch?

6 Answers  

---

what is mapping in instrumentation and control engineering

2 Answers  

---

How INtools is useful for routine Instrument maintenance?

0 Answers  

---

How to Calibrate Penumatic Transmitter.LRV= -60 URV= -20.Can u give me Answer.

9 Answers   ABB,

---

what is cold loop? difference between hot and cold loop?

0 Answers   Adani Power,

---

how do u calibrate the vacuum transmitter if it shows more reading

0 Answers  

---

how do i tune dearator pr control valve using PID. we set the set point is 0.6kg/cm2 now i want 0.5 to 0.7kg/cm2 limits so what should i give p,i,d values. then pls explain how do set pid values for control valve tuning?

0 Answers   SEWA, Sharjah Electricity and Water Authority SEWA,

---

Why we are using thrust bearing at turbine side?

3 Answers   Edac,

---

Why flow/pressure transmitter before control valve?

0 Answers   UPL,

---