Answer / alok

Modbus is communication protocol (set of rules for proper communication) developed by modicon, now it is an open protocol (every company can use it without paying royalty). In modbus we can transmit signal upto 1200 m at 125 kbps.It is used for Master- Slave application and maximum 32 devices can be connected for multi drop application without repeaters. It has many variants Modbus RTU and Modbus ASCII for serial communication it can use RS232 or RS485 protocol (depends upon distance, application type point to point or multi drop,noise immunity) and Modbus TCP/IP and Modbus Plus for ethernet protocol


Profibus is also communication protocol developed by siemens and it is proprietary (only used by developer) of siemens. we cn transmit signal upto 2 to 5 km at 12 mbps and we can connect upto 127 devices without repeaters. It also has many variants such as Profibus PA, Profibus DP, ProfiNet, ProfiSafe (used dependind upon the application)

Answer / nirav

Modbus - for connecting differnent make plc data to dcs.

Profibus - same make.

The wire is disconnected from the fuel gauge sending unit (bimetallic gauge). A voltmeter connected to the wire reads a pulsating 5v. What does this indicate?

3 Answers  

---

What is a flow meter?

2 Answers  

---

Which type of diaphragm use in costic line, dm water line, natural gas line, oil line?

0 Answers  

---

i want to make project on process control using plc.please give me idea about this.

2 Answers  

---

how the presure switches are calibrated? and what happen inside?

1 Answers  

---

---

pls tell me whethere flame proof HMI's are available or every HMI is manufactured by considering flame proof standard.

3 Answers  

---

control valve in manual/auto mode huntting checked spring tention also it is ok.positioner also good condition & incoming inst air line also constant pr.kindly give us correct answer?

5 Answers   Madhu Power,

---

Why any transmitter signal is 4-20 mA only Why is started from lower range 4 mA and upper range is 20mA.

5 Answers   Edac,

---

What are the types of control valves available

0 Answers   CCIE,

---

i want to calibrate a transmitter in the range of -100 to 300 mmwc. How it is possible to measure -100 to 300?.

2 Answers   Hindalco,

---

how far the two wire transmission (loop power) maximum distance suitable?

2 Answers   PCIL,

---

what is modbus & what signals are taken through it

2 Answers  

---