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Modbus is a protocol, a set of rules for transferring/exchanging data words between a Modbus master/client and Modbus slave/server. Modbus is not responsbile for data conversion. Although some Modbus slaves offer identical data values in multiple formats, for instance, integer, 32 bit long...

There is a good collection of packaged instrumentation amplifiers sold by Omega here http://www.omega.com/subsection/signal-conditioners-all.html This article discusses user design of an op amp or instrumentation amplifier...

1) Are you sure it's a PM9C? The C means ModbusRTU over RS-485. Models without the C do not have Modbus. No hardware/firmware, no Modbus. 2) Have you swapped A and B data lines? First thing you do when there's no comm - swap A and B data lines. 3) The PM9C has a signal common. Does...

It's a project. Modbus master/clients talk to Modbus slave/servers. The power meter is slave/server. The PLC needs to be a master/client. Check out the thread at the link below and substitute - Schneider PLC for the DCS master/client in the thread - your brand/model power meter for the...

One reason Modbus is so widespread is that is a protocol that is not vendor-specific; that is, products from different vendors can communicate using the Modbus protocol. Both devices need to be capable of using Modbus, which sometimes is an option, firmware and/or hardware. Both devices...

The first couple hits for Xenta 911 manual are documents that do not have the term Modbus. Lots of other communications options, though. What's the link to the Xenta 911 Modbus manual?

If the client/master is requesting data from Holding registers, then Function Code 03 appears in both the request message and the response message. If your examples are hex queries or responses The reqquest values =00 00 00 00 00 06 00 04 9c 40 00 00 --- Message: Line:42 success ---...

Maybe, but . . . . The Modbus standard lists a couple of Function Codes, FC20 and FC21 (decimal) (14 and 15 (hex)) named Read File Record and Write File Record, respectively. The Modbus Application Protocol V1.1b has the specs http://www.modbus.org/specs.php See Lynn Linse's and...

I'd start by looking for a MCR, a Master Control Relay, and whatever drives its coil.

Sounds like a pressure regulator. From this page, http://www.lesman.com/unleashd/catalog/valves/Jordan-Mark-66-pressure-regulator.html Click on the link to the <b> <i>Process Regulators Application Data Sheet</i> </b> for a fill-in-the-blanks sheet with selection criteria for a pressure...

You understand the situation properly. A 100 Deg C value will 'fit' into a scale 0-500 Deg C, but will not fit into a scale of 0-50 Deg C. If the value is outside the range of the scale for that point, it is handled however the HMI/DCS/SCADA handles out-of-range range data.

What sort of data acquisition/historian/HMI/SCADA/DCS is that? I'll bet it's a DCS, the graph is so bad. The X axis is supposed to be time. What kind of 'hour' is 3700, 3750, 3800, 3850, 3900? My day only has 24 hours in it. The time resolution on the lower graph is horrible. One can...

I assume that one group of sensors is manufacturer/model X and that the other group of sensors is manufacturer/model Y. There is no 'standard' for labeling the data lines. Every manufacturer picks their own labels. I've had an RS-485 Modbus product from one division within a company...

Honeywell's ST700 series is a smart transmitter, and like all smart transmitters does not have analog zero or span screws. You face an incompatibility of the Meriam 4150 HART handheld and the Honeywell. The Meriam 4150 uses model specific DOF files to communicate via HART to a smart...

The remote seal's diaphragm is large, thin and vulnerable. It is not designed for mechanical protection, like you say, it's for isolating a corrosive medium from the transmitter, as you mentioned. It is conventional practice to connect a pressure transmitter to the 'process' pipe with an...

How embarrassing, another correction: As far as I know, span is URL minus LRL. should be: As far as I know, span is URV minus LRV.

Interesting question because I actually did some arithmetic and the results don't match the spec, but hey, it's gamesmanship. As far as I know, span is URL minus LRL. Turndown is URL/(URV-LRV) or URL/span. For 0-2500mbar, the span is 2500. For 0-100", the span is 100. So 0.075% of span...

Correction: > The larger diameter capillary slows response considerably. Should be: The smaller diameter capillary slows response considerably. I need an editor looking over my shoulder.

> I think you can find the article on Bedrock's website. Walt Boyes To spare others the search: https://www.bedrockautomation.com/wp-content/uploads/2015/08/Insider-July-2015.pdf or http://tinyurl.com/j4yo4u3

Rosemount's remote seal guide, 00809-0100-4002, has a table comparing response times for balanced (equal length capillaries) with a tuned system (intended for level, direct mount xmtr on lower tap, single capillary to upper tap). The table is here...