Answer / carl_ellis

The Profibus DP specification defines the hardware transport
physical layer as 2 wire RS-485. The communications
protocol and the transport layer are both part of the
Profibus DP specification (the separate 2 wire cable for
24Vdc power supply is not involved with the communications).

Any device that passes Profibus DP certification will
conform to the Profibus DP specification.

Therefore, a 4 wire RS-485 device will not work on a
Profibus DP network because it won't be a Profibus DP
device, it does not meet the Profibus DP spec, which is 2
wire RS-485.

Attempting to operate a 4 wire RS-485 device on a Profibus
DP network will only disrupt Profibus DP communications on
the network.

Carl Ellis
Measure First

what is meant by calibration

20 Answers   Exxon Mobil,

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A temperature sensor (RTD) connected via a temperature transmitter is adjusted to give an output of 4ma at 60 deg and 20 ma at 600 deg. This output (4-20ma) from the transmitter is connected to an IGBT-inverter to control a high speed (-12,000 to +12,000 RPM) DC motor. And in the inverter it is programmed as, for 4ma the motor speed will be -3,000 RPM and for 20ma the motor speed will be +10,000 RPM. The question is : If the motor speed is +5,500 (RPM), what will be the temperature? (-sign indicates that the motion is in reverse direction).

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what is buoyancy law?

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0 Answers   ADMA OPCO,

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2 Answers   BOC, Jindal Steel and Power,

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HELLO FRENDS ,, I M IN THE MIDST OF TROUBLE .. JUST LITTLE HELP ME... SUPPOSE ,, I HAVE A CLOSE VESSELE TANK ( HEXANE MEDIA ) ,, I M USING ROSEMOUNT 2051 DPT FOR LEVEL APPLICATION .. ITS CALIBRATE RANGE IS.. . 0 TO 950 MMH20 ..I DID CALIBRATED DPT WITHOUT REMOVING IMPULSE LINE OF HIGH AND LOW TAPPING.. & WITHOUT DISTURB 3 WAY MANIFOLD..!!! BUT ,,, DURING CALIBRATION I SELECT RANGE BY HART LRV IS 900 MMH20 & URV IS 1300 MMH20 ,, BUT ,TANK LEVEL SOMETIMES 100 % AT 1100 MMH20 , SOMETIMES 1300 MMH20 ..IN THIS CONDITION .. WHOLE LOOP FAILED ,, MAIN THING IS THAT ,, HOW TO CUSTOME RANGE SELECT ?? AND IF I USED RANGE OVER THE ORIGINAL CALIBRATE RANGE ,,,THEN WHAT ERROR WILL BE COME ??? HOW TO ZERO CALIBRATION OF DPT... HOW TO ZERO TRIM BY MANIFOLD ?? AND FOR TANK LEVEL PURPOSE ... WHICH UNIT I CAN USE ??? IS THERE ANY CALCULATION OR CALIBRATION .. IF YEH .. THEN PLZ JUST GIVE ME CALIBRATION STEPS FOR DPT.. THANKS YOURSSSSSSS

1 Answers   Torrent Pharma,

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what is instrumentation?

8 Answers  

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