why we use 4-20 mA to do calibration of the instruments.why
we cant use 0-20 mA?
Answer Posted / seshu
if we use 0 to 20ma, if any case cable was damaged then it
gives 0ma signal. so we r using 4 to20ma
| Is This Answer Correct ? | 7 Yes | 5 No |
Post New Answer View All Answers
Isometric drawings are generated during _________________ phase of a project
why I need valve guard and whats different between guard and positioner ??
How many interlocks at turbine side?
what is output of FOUNDATION FIELD BUS transmitter
what is difference between HOT permit and cold permit
what is KV and XV valve
what are the documents(Construction point of view for a process plant) submitted by contactor initially entering in to new site for client?
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 ?
How is PH sensor works ?
what is intrinscily safe system and where we use?
Define the difference between a stable versus an unstable controlled system and some of the tools you might use to be able to detect when this is happening and assumptions used for control system application design that could contribute to instability
What is cut off relay? And why use in PLC and DCS?
any one can send me instrumentation previous interview papers? I prepare for MNC Company Interviews? my mail id- Rakesh.Golla@dodsaldxb.ae , and another mail rakesh.gvk@gmail.com
Please send me the sample question of Instrumentation of hpcl/iocl exam. my mail id hihi_kiholo@rediffmail.com
why direct mounted pressure transmitters is always installed with DBB ( double bleed block) valve in process line or top of the tanks ?