what are the standards used for earthing instruments in the
field?
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
1)How many tpes of vibration probe and how many tpyes of vibration. 2)how we can calibrate a vibration probe with tk3 3)what is RMS value in vibration measuring application and how we calculate it.
What is furnace draft control?
Can anybody please let me know Orifice plate sizing calculation formula and step by step procedure
Using your own examples solve a problem involving normal table. (experimental method and analysis)
send me model hpcl questions pleas..........my mail id mohideen.dharvesh@gmail.com
I am having a Phoenix digital to modbus converter. The o/p of the same is connected to flow computer FB407. But the digital signals are updated only after one minute in the flow computer. what may be the cause of delay in communication? Flow computer is having a scanning period of less than 1 sec.
Regarding , there is an air cooler which control the fans(50% of AV FANS) by temperature in outlet , and the louver of Air cooler is controlled by HIC from control system , So if on Air cooler we will consider 2 individual I/P converter or positioner?
What is the use of single seated valve?
How is PH sensor works ?
Yokogawa CENTUMVP R6.09 unable to download to Engineering Station with ExaOPC R3.75
The issue is when I try to download the common project section to the Engineering Station (STN) from the HIS in System View, it is unable to connect. The error displayed is:
WARNING: Could not connect to equalize destination. (7001)
Retrying. Number of retries = 0/1
ERROR: LdXopsLoadMain: connect error 10060
ERROR: Processing terminated due to connection error. (7002)
Equalization end with errors. STN0149
---- ERROR = 2 WARNING = 1 ----
Background:
>Updated the ExaOPC software on the STN from 3.60 to 3.75
>STN operating system is Windows Server 2008 R2
>HIS operating system is Windows Server 2016 Stanard
Solutions attempted include:
>Ensuring all IP addresses are correct and all networked devices can be pinged.
>The ability to ping a device using its host name from another device (
What is Cavitation in a control valve?
what is function of SCADA , and how is it work, explain with difination
Tell about your IFFCO plant visit.
detail of mass flow meter pricipal
What is the use of temprature compensation?