what do you mean by Loop checking ? What are the cold loop
check and hot loop check? what are the difference between
these two loops?
Answer:
A Cold Loop check is cold because it is done without
powering the loop.
A cold check consists of checking wire continuity from the
field instrument through junction boxes and through DCS/PLC
marshalling panel terminals to the control panel. Once
continuity has been confirmed, then a Hot Loop Check is
performed on the Loop's I/O.
A Hot loop check is 'hot' because it is done with the loop
powered up.
A Hot loop check consists of
- simulating a process input at the field instrument and
then checking the instrument's output and the response to
the process signal input at DCS/PLC.
- simulating outputs at the control end and checking for
correct response at the field end.
Carl Ellis
Measure First
| Is This Answer Correct ? | 5 Yes | 1 No |
I wnat to practice more online type questions .so will you show them me to take a practice test?
Why we are using 4-20 mA as Analog signal transmission other than 3 to 19 or 2 to 18 or 6 to 22 like wise ? What is the reason behind using 4 & 20 mA? Can anyone give proper technical reply ?
Draw a complete P&ID of a flow suction tank indicating all control & protection equipment. Indicate all its inlets and outlets. Explain the controls for this system
how u meassure room temp?is it possible 2 meassure room temp by rtd or thermocouple?between rtd n thrmocouple which is more regard?3 meassure diff. between rtd n thermocouple?
what is the minimum power (P=VI)to produce a spark?
Describe all types and levels (4-20mA, 0-10V, mV, pulse, etc.)of analog and digital I/O used in process control application.
Could anybody tell how much amps will a single input to plc will consume?
whyvibration probe (bently nevada ) is set -10 volt for zero reference?
difference between null and deflecting instrument.
please tell me five types of fault of control valve and positioners?please
In dissolution apparatus how did you calibrate the distance from end of paddle to bottom of the bowl?
what is an ambient temperature?
Civil Engineering (5086)
Mechanical Engineering (4456)
Electrical Engineering (16639)
Electronics Communications (3918)
Chemical Engineering (1095)
Aeronautical Engineering (239)
Bio Engineering (96)
Metallurgy (361)
Industrial Engineering (259)
Instrumentation (3014)
Automobile Engineering (332)
Mechatronics Engineering (97)
Marine Engineering (124)
Power Plant Engineering (172)
Textile Engineering (575)
Production Engineering (25)
Satellite Systems Engineering (106)
Engineering AllOther (1379)