Answer / carl_ellis

No, it is not possible to convert a 4 wire device (power on
2 wires, output signal on 2 wires) to a 2 wire, loop
powered transmitter.

A 2 wire loop powered transmitter uses 3.7mA of the current
loop to runs its electronics. That's why the 'live zero'
starts at 4.0mA, so that there's some power avialable to
the transmitter's electronics.

There's lots of technologies that cannot run on the limited
power of approximately 3.7mA at 24Vdc. Thermal dispersion
flow meters, most wet cell gas detectors, thermal
ionization detectors, to name a few, which have to be 3 or
4 wire devices in order to have sufficient power to operate.

Carl Ellis
Measure First

Answer / amit

it's function ablavale in transmitter otherwise we do not
convert them.

Why do we go for 4-20mA? why not other standara?

6 Answers  

---

how can be calibrate flow indication transmitter (rosemount) it shows excess milli amps nearly about 24 ma on full scale, but its scale was set on 20ma on full scale..???how can be simiulate..???

0 Answers   Siemens,

---

WHAT IS AN INTERLOCK SYSTEM ?? HOW THEY WORKs ?? WHERE IT IS USED ??? MAINLY ??

2 Answers   TATA, Tata Steel Limited,

---

Differentiate between PLC, SCADA and DCS systems

1 Answers   Mumias Sugar, SRF, Trimula Industries,

---

what is different between 2,3&4 wire rtd and how much maximum distance using plc to field.

0 Answers  

---

---

Why using negative voltage in vibration measurement?

2 Answers  

---

how can we calibrate RADAR LEVEL transmitter 0% to 100%

3 Answers   Chevron Phillips, Honeywell,

---

To calculate temperature, why we multiply 25 with mV?

2 Answers  

---

what is the procedure of belt scale calibration?

0 Answers  

---

where uses EXe /EXd/Exo/Exn/Exp/Exq/EXia

0 Answers  

---

hey any one got the papers of SAIL and HPCL plz do help me by posting them to my mail ID's naren07_87@yaho.co.in, surenarendra@gmail.com

0 Answers  

---

What are different types of orifice plates?

0 Answers  

---