what are the standards used for earthing instruments in the
field?
- 1 Answers
- 6667 Views
- I also Faced
- E-Mail Answers
Answer Posted / 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
| Is This Answer Correct ? | 3 Yes | 0 No |
Post New Answer View All Answers
What is intrinsically safe system?
what is KV and XV valve
what about your moleg in pogrees with company
Why rdt and thermocouple both give different output .and one things more, how to generate ohm or mili volt plz mail me merajalam143545@yahoo.com
Explain working principle of lvdt?
What is Span Error
Explain PID controller tuning & any one method used for it.
what is commisioning procedure,2)what is is the main work in commisioning in the field tx to dcs, plz send me detail
What are the different types of thermistors used in industries? How to the operation of typical thermistor?
In turbine what does term CDP, NI, NH, HSSOC means.
Hi, Is there any smart plant instrumentation design training institute in Bangalore?
this site is owned by an nonsense
how many pulses are required by a ac induction servo motor of 4 poles with 50 Hz frequency to rotate by 1 degree?
which type of zones used for boiler? & why ?
selection of the zener barrier for the hazardeous area zone 0
