Answer / a.naresh

PROFIBUS is a vendor-independent open bus system. It has three types namely:
1.PROFIBUS-FMS (Fieldbus Message Specification
2.PROFIBUS-DP (Decentralized Periphery)
3.PROFIBUS-PA (Process Automation).

## The DP variant (decentralized periphery) is the high-speed solution of PROFIBUS. It has been designed and optimized especially for communication between automation systems and decentralized field devices. Therefore,PROFIBUS-DP requires less than 2 ms for the transmission of 1 Kbyte of input and output data. In this way even extremely time-critical communication tasks can be solved.PROFIBUS-DP communicates via cyclic data traffic exclusively.Each field device exchanges its input and output data with the automation device,within a given cycle time.

##In process engineering as well as in process automation,operation and monitoring tasks require a visualization device in addition to the automation device. This class-2 master is responsible for the various
start-up, parameterization and monitoring functions of up-to-date field devices.They require that device data be read or written during operation independent of the control cycle.
PROFIBUS-PA meets these special requirements of process automation.
The important characteristics of profibus PA are:
->intrinsically safe transmission techniques.
->field devices are powered over the bus cable,
->reliable data transmission, and
->interoperability (standardization of device functions).

If 3-Ph motor of same rating connected in Delta & Star for same load one by one then which connection take more current in running (not in starting)for full load.(eg 8.5 KW,3-Ph 400 V)

1 Answers   GE,

---

We have got the HT connection of 1000 KVA in which we have installed a seprate APFC panel at the PCC end & seprate KWH meter is installed. My question is that does the KWH reading shown in the meter is a part of the Consumption ???? ( approx 500 units is shown)

1 Answers  

---

How much pole motor can be desion for 415 volt ,50 hz.Power supply. in pratical condition . Prakash veer singh

5 Answers  

---

how to calculate distance between busbar supporters for LT panel, what are the factors influencing in this design

0 Answers   Amara Raja, TATA,

---

what is the difference between pvc & fiber glass cables

0 Answers  

---

what is the meaning of trippe time of circuit breaker

1 Answers  

---

wath is skin effect?

9 Answers  

---

how much insulation resistance 11kv & 33kv under ground cable between earth to phase & phase to phase.

4 Answers   Siemens,

---

what is the tolerance of electrical frequency for India? it's .5% or 1%?

8 Answers   Engro,

---

why DG battery blast

2 Answers  

---

how to calculate relay rating for 50kw load

1 Answers   JNU,

---

What is the measuring instrument of magnetic flux density?

2 Answers   CSEB,

---