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Partial or full stroke testing is part of the SIS protocol. Check out a valve stroke testing paper here: https://tinyurl.com/y2x7jg2b

Yes, you can read the bit coded status of the interlocks wired to the S7830A annunciator from register (4)0015 and the first out from register (4)0014, reading from the RM7810M module on the RM7800L.

The RM7800L's is a flame safety 'programmer/controller' that sequences through the ignition process. The Modbus register (4)0003 is the Sequence State. A programmer/sequencer has only one state at a time. Table 22 shows the overview of the states: initiate, standby, purge, Pilot Ignition...

It is the change in dielectric constant that produces the signal change in radar devices. The simple app, shooting water, is the change in the dielectric of air (low) versus the dielectric of water (high). What your particular device does with a setting for dielectric constant is an...

The manual here http://www.kael.com.tr/eng/pdfler/MULTIMET-01-PC%20eng.pdf states on page 9 that the device can only reply with one variable per Modbus message/transaction using Function Code 03 (read Holding Register). The RS-485 wiring has Sg (signal ground) driver lines A and B, and a...

The pipe-fitters always seem to take care of supports without a lot coaching. Sometimes close coupled to a root valve. I have seen pipe, as opposed to tubing, used on occasion for support. Slide 24 at Slideshare has AS-Schneider (Germany) supports for valves and measuring instruments...

The issue is probably "some slaves are not responding". Although I've seen networks overloaded with Ethernet/IP traffic where the slow Modbus/TCP comm was due to an overload of Ethernet/IP broadcasts. A managed switch helps the Ethernet/IP traffic situation; but will not help a 'slave not...

Any chance this question is for the same location discussed earlier this year, in May? https://control.com/thread/1556635757 This is a classic case of unequal heating of the DP capillaries and seal fill fluids inside the capillary. A filled capillary is a 'closed system'. Either Charles...

Not really my field, but I read this paper once and it covers issues with ESV MAST calcs and might provide a direction for you: http://www.iceweb.com.au/Valve/SDV_BDV_ESD_Valves/NeedIndustry%20std.pdf

I assume you're not running at baud rate that exceeds the RS-485 spec. What are segment lengths and baud rates? For what it's worth, Profibus DP is an engineered RS-485 network. I find Profi's DP segment cable length maximums more conservative than the standard RS-485 baud-vs-cable length...

I assume your question is mapping a slave device's variables to a register map. Technically, yes, you can map whatever you want where ever you want, but you have take into account that for a commercial product, how useable is it? For discrete/binary values, bit packing is already...

Does the Modbus-read value actually go to zero? Usually comm failure (over a serial link) results in stale (last valid point, never updated) data in the master that 'straight-lines' when charted or graphed. Data values that are Zero is typically the result of initialization or...

It sounds like you've actually had quite good service from all the other transmitters, except this one. Speculation on possible faults: - the power failure tripped a valve that created a water hammer pressure spike that damaged the pressure sensor - that particular PT is the 1 in xxx...

I'm not sure, from your description, which device reads and which device writes or whether you've gotten the network to operate normally at some point. I'm not sure what 'auto COM port reset' is, but that sounds like something that shouldn't need messing with, once things are running, at...

1. >If I move lan cable to PC, then it works on Aurora. That means your RS-232/RS-485 converter and PC serial port is working, right? This is when Aurora sofware communicates via the Trio's PC port. A PC's serial port can not be shared by two different applications (or services)...

I've got one spec sheet on my desk for a DIN rail mount temperature transmitter that has a 135mS update rate, and another spec sheet for head mount TT has a 500mS update rate. If update rate is important, then you'll have to shop for a transmitter that meets your requirements.

>In our plant thermocouple sensor are transferring mv to marshaling cabinet. Answer: Thermocouples generate a mV signal. I assume this means that the raw thermocouple mV signal is sent to the marshalling cabinet. Is this correct? >Then a transmitter barrier change it to 4-20 and goes...

The purpose of the I/S barrier is to prevent electrical faults (over voltage) in the safe area from getting to the I/S device in the hazardous, where the fault could damage the device and create an arcing-sparking ignition source. No barrier; no protection from faults on the 'safe' side.

The Yokogawa YPP6200 is a private labeled Precision Digital PD6200. There is no published pinout for the M-Link connector. The M-Link connector is a USB port, natively used for Precision Digital's MeterView Pro configuration software. The M-Link connector does NOT have RS-232 or RS-485...

You are correct on the overlap of 6 digit vs 5 digit addressing, but I think the OP is looking for code with which to write his own app that supports a full 65K memory space, not the limited, earlier version code that only actually addresses 10K registers.