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RTD's can drift. That's why people do loop calibration with a dry block or oil bath because a loop calibration takes into account all the elements of the loop - sensor, wiring, analog input, receiver configuration and display, as you recognized in your post. Another approach is have a second...

Heat?

1. Offset of 1 Usually 'offset of one' is used to explain the difference between counting starting at numeral zero and counting starting at numeral one. A one-based decimal address is one higher than its equivalent decimal zero based address. Problem is, your map is zero-based, starting at...

There is no manual override, despite the government boondoggle financed dreams of the climate controllers. We can't control the sun or the earth's volcanic activity.

https://www.electricalclassroom.com/proximity-sensors-types-applications/

Modbus Rule: Modbus slaves are silent unless spoken to. Modbus Rule: The Modbus master sends a command that either requests data or writes data to a slave. Modbus Rule: The slave responds with either the data requested or an acknowledgement that the data was received and written...

Ironically, I just ran into a GWR unit rated only for atmostpheric or positive process pressure, so apparently it becomes important to know whether the GWR in question is rated for vacuum service or not.

Did the network ever work properly for long periods of time or is this a commissioning issue? What makes you think the read and write values should not be different? Is there one write command for every read request? Is there not an actual error log with a good vs bad number of transactions...

Every GWR spec sheet I've seen has a process pressure rating of -1 bar, about as vacuum as you can get. What does your spec sheet say?

Lots of things can cause a comm card failure, nothing specific to Yokogawa or its protocol/network Electrical It only takes one transistor of the hundreds of thousands/millions to fail and the logic or memory is bad. Non-Volatile memory can fail after X thousands of write cycles It only takes...

Would this cause issues with reading the temp? No, that is not a problem; using 3 of 4 wires is a conventional 3-wire RTD circuit. Is this a common practice for installations? No, it is not common because most vendors charge something additional for a 4-wire RTD and if the 4th wire is not...

In answer to your question, should these 10K Type 2 thermistors read 77°F at 77°F, the answer is yes. Here's a chart and statement the differences between Type 2 and Type 3 thermistors as the temperature moves away from 77°F: and a table of resistances: The go-to overview of RTDs vs...

You missed some critical information on flow meters. What is the flowing medium, at what pressure and temperature? How much pressure drop can the system tolerate? How viscous is the medium? Is it conductive or not? Is it a corrosive medium? What minimum level of accuracy is acceptable? As...

You are right, wire is not an issue. 18g copper wire has a resistance of 6.5 Ohms/1000 feet. A 100' run out and back is 200' total with a resistance of 2.1 Ohms 2 Ohms is only 0.02% of the nominal 10K Ohm input, insignificant. And a 'increased resistance due to wire resistance' issue would...

As others have pointed out, the sensor is a thermsistor, not an RTD. 77°F = 25°C, reference sheets are frequently in °C. Yes, 10,000 ohms should read 77°F, if your ID statement is correct. I suspect that your 5% 10k Resistor is not a very good means of checking the controller's input...

which network? Profibus PA is different than an office LAN.

Reading your post made me yearn for the days when manuals had a 'theory of operation' that described what you're looking for: a description of how the fault alarm is generated. I have zero knowledge of Triconex, but I do know that some SIL 2 controllers monitor an AO to determine - if the AO'...

Early 20th century advertisements for LEA coal flow meters

You might want to read post #15 for an overview approach to executing control projects http://www.plctalk.net/qanda/showthread.php?t=128184

Back in 2014, I looked at Quadax who had recently introduced a four offset valve that could allow for a replaceable PTFE o-ring seat. At that time, all triple offset valves were stellite seats, due to the wear factor inherent in the design. I haven't tracked that market/application since, but...