I HAVE PRESSURE TRANSMITTER WITH TWO WIRES 24 VOLTS SUPPLY.IF
TRANSMITTER WILL GIVE SIGNAL TO THE DCS WHAT HAPPEN TO THE 24
VOLTS POWER SUPPLY IT WILL DROP OR REMAIN TO 24 VOLTS POWER
SUPPLY.
- 3 Answers
- 6420 Views
- I also Faced
- E-Mail Answers
Answer Posted / carl_ellis
You describe a situation with a 24Vdc power supply, a 250
ohm dropping resistor and a 2 wire loop powered transmitter
at 4.0mA
To get the voltage to vary across the transmitter, you have
to change whatever the transmitter is measuring to get its
output to change, or force an output with a HART
communicator. The loop current does not vary on its own,
it varies in response to whatever the transmitter is
measuring.
Carl's Loop Rules
The voltage across the power supply remains constant: 24Vdc
The voltage drops across the transmitter and analog input
vary with the current in the loop.
Assuming a bench setup with very short wire runs and a very
low wire resistance, then if the analog input dropping
resistor is 250 ohms, then
at 4.0mA the transmitter drops 23.0V, the AI resistor drops
1.0V
at 12.0mA the transmitter drops 21.0V, the AI resistor
drops 3.0V
at 20.0mA the transmitter drops 19.0V, the AI resistor
drops 5.0V
The sum of the voltage drops must equal the power supply
voltage.
You can bank on it.
Carl Ellis
Measure First
| Is This Answer Correct ? | 2 Yes | 0 No |
Post New Answer View All Answers
how to work static pressure sensore how to work dpt
What is the calibration procedure of Drum level transmitter if range is 0 to -400 mmh2o in lab?
What is standard procedure of manual mapping in Radar type level transmitter?
What are the interlocks we have to check during the start up of LP/HP compressor?
What are the materials available to prepare individually for competetive exams in Instrumentation field? Plz reply...
I wnat to practice more online type questions .so will you show them me to take a practice test?
how will you check torque value during Factory acceptance Test for control valve/ESD ON/OFF VALE how will you confirm this torque value is being correct, Which document will you be refer.
What is Cavitation in a control valve?
Explain the working of rota meter.
Decibel.
Isometric drawings are generated during _________________ phase of a project
use of split range ? where it is used ? in which control loop it is used ?
Derive capacitance to 4-20ma conversion formula / relation in capacitance type pressure sensor?
What is stripper & spilitter ? Diffrence in this.?
please send the drdo exam paper
