Explain about 4 wire instrument concept & tell about its
wiring fron sensor in Field to PLC panel.Explain with an
example?
Answers were Sorted based on User's Feedback
Answer / ranjith_asp
As the name suggests, these instruments will have 4 wires
connected to its Terminal Block. Take a Pressure Transmitter
for example
- 2 wires are for Power Supply. Typically 24VDC. This is to
power the instrument to make it work. These 2 wires will be
routd via a JB and then connected to a power supply module
in the PLC cabinet.
- remaining 2 wires are for 4-20mA signal transmission. This
output signal will be proportional to the measured Pressure.
These 2 signal wires will be connected to the AI card in the
PLC cabinet.
Is This Answer Correct ? | 6 Yes | 0 No |
Answer / hadi
4 wire connection sensor have two methods:
1-sensor's power is provided from card
2-sensor's power is provided from field
in first method the power is +24VDC and the current limit
exist but in second method the power is every thing and
transmitter feed from external power supply.
in two methods the signal lines and power lines are different.
Is This Answer Correct ? | 6 Yes | 2 No |
Answer / ramaswamy and karuppusami
Usually in 2wire transmission, 24v supply is given and o/p
in mA are taken through single pair cable. e.g: Transmitters.
But in 4wire system, supply is provided in separate single
pair cable and o/p is taken through another cable. e.g :
local speed indicator device: i/p = 230v and o/p = 4-20
mA(Both are in separate cables ).
Is This Answer Correct ? | 3 Yes | 0 No |
What is the formula of vabration sesore. i mean how to covert mils to volt plz share if any body knows very argent : my mai is merajalam143545@yahoo.com
What is the DIfferences between SMART transmitters and PROFIBUS DP/PA Transmitters?
i want all model questions paper for robert bosch
Can we used Condensate Pot on flow transmitter which is using on liquid having sluge and DP transmitter is in pit and below the process line,Can we used Condensate pot for accamulate the Sluge?
sir ,iam in dem urgent need of HPCL Paper of Instrumentation Branch plz send me at your earliest convenience at ujjwal_sharma1983@yahoo.com
Please any one can explain how to calibrate transmitter (smart) online with out remove from the container suppose it is interface level or static pressure level measurement we dont want to remove transmitter from the container mean it is running plant please give me detail. thankx brothers
Will Intergraph support SmartPlant Instrumentation in an AutoCAD or MicroStation environment on a long-term basis?
What is the difference between mmwc and mmwg?
There is a problem with our HART475 it is not communicating with smart devices error becomes "NO DEVICE FOUND"we have insert 250ohm resistance as per requirement but invain plz tell me the solution?
how to use level tranasmitter in closed tank application.?
Hello friends i need check lists of different instruments during the Erection and commissioning in thermal power plant.Please help me.My Mail id is naba02222@gmail.com/naba02222@rediffmail.com Thanks Nabakishore Biswal
pls tell me whethere flame proof HMI's are available or every HMI is manufactured by considering flame proof standard.