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You need to post a URL link here to the English language manual that covers MODBUS for the energy meter.

Thank you, Dick, for your detailed explanation. Well done. I'm delighted to hear that the question has been abandoned for the exam. It's too bad that the web page isn't clear that it's an abandoned question, because it sure looks like the example of study question.

I say, either, or both. HART is definitely digital capable, but in practice HART is primarily used for configuration, troubleshooting, calibration and diagnostics. Its use in or for control is limited by - I/O availability - only DCS and high level PLCs have HART enabled I/O at a...

My crystal ball is too hazy today and I failed clairvoyance 101 so I'll have to provide conventional reference material links. The higher than 20mA output is the classic fail-safe mode, which indicates a critical fault. The critical faults are listed in table 49 in the ST3000 HART users...

You'll need a PLC, software to program it, a cable over which the software talks to the PC, a PC, and presumably some lights and switches to simulate intersection traffic lights. I doubt you need actual vehicle sensors (due to cost); ordinary switches can simulate the function. On the extreme...

Clearly, the difficulty you're seeing is associated with the upgrade. Something changed. Problem is, there's no response 3 days later because you've isolated most of the forum readership, who, like me, don't have a clue what is involved in a MkV to MkVIe upgrade. I can see a peaker plant...

What happened to me recently is not an answer for what is wrong in your situation, but it shows how what appears to be a bad thermocouple or a bad thermocouple card is neither and the situation requires more effort to figure out what's wrong. I had a thermocouple problem last week on an 8...

The atmosphere outside the vessel is pressing in at a pressure of 1 bar. If the liquid head pressure and the vacuum combine to be less than 1 bar pressure inside the vessel at the lower port, then air could leak into the vessel. Is the liquid level times its specific gravity plus the...

How in the world do you observe 'air' being sucked from the Low side impulse line? How is it possible that you observe it? Why would there be 'air' in the low side impulse line in the first place? Do you make an effort to make sure there is liquid fill fluid in the lower impulse line...

That IMT has a removable cover on the front, "for connecting external devices such as a PC-based configurator or a HART communicator." Hmmmm. What happens behind the scenes is frequently not supposed to be revealed to the public. ("Who is that man behind the curtain? asked Dorothy)...

> Vent the transmitter Low side to atmosphere Well, this all went down 3.5 years ago, so it's now a moot point, but this application is not a 'vent-low-side-to-atmosphere application. He was properly using a DP transmitter with the low side connected to the nitrogen atmosphere blanket...

Roy, Just so you know, my comment about not paralleling 4-20mA was a reply to the original poster, Mr. Nguyen. Your comment wasn't posted when I replied, and my post only shows up after yours sequentially because of the date stamp for when it was submitted. I was saying the that...

I can imagine a couple approaches. 1) A repetitive, frequently used message, like a command to the field device, is configured in the gateway. Your Modbus master triggers it to be sent as an ASCII command from the device side of the gateway, for instance write a value 1 to coil address...

Paralleling the 4-20mA will not work. You can try running the 4-20mA through both AI's in series. Sometimes it works OK, other times it doesn't because of the ground loop caused by the different ground reference of the devices. Every commercial 'splitter' that I've seen isolates the input...

That might be a serial connection limitation. RS-232 is point-to-point and supports only one device talking to another device. There used to be A-B switches for 9 pin D connectors that switched RS-232 from port to port. RS-485 is multi-drop. Sometimes a work-around for...

> Can I purchase a device which will allow me to use one Master to two (2) slaves devices? You shouldn't have to. A Modbus RTU master can read/write to any one of multiple RTU slaves on an RS-485 multidrop network. That's conventional Modbus. But I suspect that - the boiler module is...

It doesn't take much to determine the DP. Do a Google images search for orifice plate with water tube manometer to see a number of images on a how a length of vinyl/tygon tubing with some water in it which is connected to a couple taps/ports. The DP is the difference in water column...

I'm sure there are dozens, but here's two that have 3rd party certification: Honeywell STT850: http://tinyurl.com/ndn8dge Siemens TF: http://tinyurl.com/q447zh2 Input devices by themselves do not constitute a Safety Instrumented System at any level, regardless of their certification.

> the article recommends piping the low side of the AFS to the inlet side of the filters and facing the tube end into the flow of air. <snip> > It seems to me that if a blower is blowing air through a filter, the filter would create resistance to the air flow and that this would cause...