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What tasks are you doing that you need a protocol analyzer for? I've connected devices to Modbus enabled recorders (both as master/clients and slave/server), but have never needed Wireshark to analyze the serial or TCP traffic to get them working, but I could have been lucky. The...

1) What is PMC? 2) What does 'detect some devices' as "healthy" mean? Does it mean that you can send a valid Modbus request and get a valid Modbus reply? Or something else?

An absolute pressure transmitter with a reference zero of 0 mbara will act as a barometer. Comparing an absolute pressure transmitter's measurement (with its pressure port open to the atmosphere) with the local weather station's barometric pressure is a way of determining whether the transmitter...

Correction: WinTech Modscan32, not WinZip.

The lack of any response indicates a likely lack of functioning communications hardware (assuming you are not testing your own Modbus master code). I would suggest following Dr. Leo Marvin's advice: Baby Steps (What About Bob, 1991) Baby Step 1 Do the slaves actually have Modbus? Modbus is...

The gauge pressure transmitter should read 4.0mA when it is open to atmosphere with the range cited: LRV = 0mbar, URV = 2000mbar. A correctly functioning absolute pressure transmitter ranged 0-2000mbarA (absolute) should read about 12mA when open to atmosphere, because 1 atmosphere is approx...

1) Make sure you can isolate the transmitter from the process. 2) Use something like the GE Druck DPI610P handheld calibrator which has ranges from plus/minus 1 to plus/minus 60" wc. I'm sure there are other brands/models. Otherwise, there's clear tubing, water and a yardstick/rule)...

Lots of reasons given in this thread on HART communications: http://control.com/thread/1458336806

The data sheet probably does not have as much detail as a manual or users guide has. Look for a users guide or manual. The main methods used to configure a Modbus slave ID on various devices are - DIP switches - rotary switches - jumpers - software access to the firmware - pushbutton...

3Km maximum. Here's a link to a table from a whitepaper, 00840-0100-4075, Rev AA, by Emerson/Rosemount. http://s32.postimg.org/vd581fz11/Emerson_HART_cable_guidelines.jpg Since they invented HART, they're probably in a good position to make the statement.

Any DCS should have a "track and hold" function, you just have to find it. Search the function block manual for the word 'track' or 'tracks' Honeywell's Process Automation Controller, the HC-900, has a function block named TAHD, Track and Hold, that "provides an output that tracks the...

If the flow computer, field transmitter and active barriers all need to be battery powered, then you need to know how much power they all consume in order to size the battery and its charging system. Putting it in a Cl 1 Div 1 area will be interesting.

The inability to navigate past the TUNING and SPRAMP groups means that a security setting for LOCKOUT is set to +VIEW or Max. http://s23.postimg.org/j8is8gl57/Lockout.png The LOCKOUT group is found by using the FUNCTION key to move through the functions in the TUNING group...

> Please give the capacity of adapter i.e. 3v ? ampere etc to run the electronic instrument. No one here knows what number that is because that number (current draw) is determined by the electronic instrument. It might be on a tag or in a spec sheet or manual. You could measure the...

At that temperature and vacuum level, there could be temperature or vacuum influence on the measurement. The transmitter vendors publish an operating conditions limit chart for vacuum level vs temperature, usually for a specific fill fluid, like the one here...

Page 39, section 6.2.2 of the Modbus specification <i>Modbus over serial line Specification and Implementation guide V1.02</i> has 5 pages with a logic flow chart for generating a CRC. Download the spec from Modbus.org

Those MoSi2 elements need softstart SCR/thyristor control that limits current when cold or mulit-tapped transformer. Check out Kanthal's power control comments...

I know that industrial pressure transmitters provide a choice of head pressure units that can include water (density) at various temperatures, like mmH2O at 4 Deg C or at 0 Deg C. I'll trust the on-line calculator at http://antoine.frostburg.edu/chem/senese/javascript/water-density.html...

I'm not a Siemens guy but I saw this post and bookmarked it. Check out the last post in this thread at the link below regarding pointers for arrays. http://www.plctalk.net/qanda/showthread.php?t=99994&highlight=MODBUS+RTU+Micrologix+S7-1200 I believe that the function block you show is a...

Historically in ultrasonic velocity measurement, a narrow beam or shear mode energy beam from the transmitting transducer relied on stable propagation conditions in order to hit its target - the receiving transducer. Changes in sonic velocity due to temperature or fluid composition could cause...