Recent content by David_2

What is a 'duty parameter' on any On-Off/PID controller?

The manual (pg 75) for the FMR67 tells you to do the mapping function: https://bdih-download.endress.com/files/DLA/005056A500261ED897EB6ACB746ADB96/BA01620FEN_0218.pdf

I've seen a circle with LT or LIT or LZT (safety) with the letters RDR or the word Radar printed next to the circle.

>In Modpoll software i select range of modbus addresses from 200 to 340 That attempts to read 140 registers which exceeds the Modbus maximum limit of registers-per-read-transaction of 125 registers (quantity of 250, 16 bit bytes). Slave/server devices can have their own more limited maximum...

So you read (4)0201 through (4)0221 with Function code 03, in one transaction and you get good data in all the registers. Then, in a separate transaction, you read (4)0271-(4)0282 and you notice that (4)0201 through (4)0221 has changed? Where did you 'put' or move the data from (4)0201...

I'll bet it's the switch behind the push button actuator that's the real problem, not the pushbutton itself. I doubt that replacement switches are available from Auma, but they're the ones to tell you that, not me. It's more likely that Auma sells the entire display unit as a spare part...

On the clamp-ons that I've used, a positive reading is forward flow and a negative reading is reverse flow. The connection of the sensor cables to the correct terminals determined the polarity of flow value, meaning that reversing the cable connections reversed the flow polarity. There's...

1. measured TEMPERATURE by Thermometer is OUTPUT of field device(SALVE), but this signal is INPUT for PLC(MASTER). Correct. A temperature transmitter's input is an RTD or thermocouple sensor. A temperature transmitter's output is a scaled 4-20mA signal proportional to temperature. A PLC's...

I stand corrected. The initial draft and versions of the User Manual had to 20/21 register addresses, but only just now did I realize that the latest version 2800 User manual that I linked to above has the standard register addresses for integers, but the user manual still lacks the floating...

Isn't this a Purchase Order/checkbook situation?

If you're going to roll your own HMI, then there are some things to be aware of: 1. You need to download the UDC 2800 vendor manuals: For the UDC 2800: User manual R200.0 rev 8 51-52-25-157 Sept 2023, not an earlier version. The Modbus maps are for Function Codes 20/21 which are rarely, if...

Reading/Changing SP, PV and OUT This is nitty gritty stuff but it's critical to understanding what all you need to make this work. Modbus is a just protocol which is a set of rules for communication. The rules cover things like who talks, who listens, how a connection is established, what...

As found: FC01 & FC03 : is to read OUTPUTs of SLAVE. (Memory area named Coil & Holding Register respectively). for example : A binary sensor when it is ON or OFF. These ON or OFF will be READ by FC01. An analogue value such as temperature or pressure value will be READ by MASTER by FC03. Should...

Yes, I can help you from the UDC2800 side, but I don't know one end of snake from the other, so you'd be on your own for Python coding. But I need to make sure that the magic of Modbus will actually move you toward your goal, because I have encountered numerous situations where invoking the...

There's an inexpensive book that covers the basics of Profibus, Catching the Process Fieldbus: An Introduction to Profibus for Process Automation. by James Powell. Profibus installations should use Profibus cabling and connectors because their designed for the hardware layer operation...