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The question is about 5 bit (4xxxx) or 6 bit (4xxxxx) addressing. One earlier thread (Aug 27, 2002) discussed it: http://www.control.com/thread/1026155725 I guess an open protocol leads to 'open' terminology for discussion purposes.

Everything effects 'accuracy'. Everything like temperature, aging, line pressure, hysteresis. So, the answer is, "Don't know. It depends on the brand and the model." You need carefully read the spec sheet of the device very carefully. You'll notice that all the smart transmitters...

Oops, I stand corrected. In my earlier post, I was thinking ordinary copper wire was the extension wire, not Type T extension wire. Type T wires are copper and constantan, not plain copper. The Law of Intermediate metals would not apply to a junction to dissimilar metals. I agree...

Here's my rationale on the topic: I don't think the error is a linearity question related to thermocouple composition. The error has to do with temperature gradient. If there's no temperature gradient across the copper wire, and the connection points from T/C wire to copper extension...

A modem converts one communications medium to another, like in the old days, a PC's binary RS-232 to modulated analog tones for telephone line transmission, and then back to serial on the other end. A pair of wireless Modbus modems will convert from wired Modbus/serial/TCP to wireless and...

A zero effect error applies across the entire span of the instrument as an offset or bias value, so instruments used in applications where a zero shift can be significant are more closely examined for the effects of temperature and pressure on the device's zero. There is general consensus...

The effect of temperature, mechanical alignment issues, a dysfunctional liquid-fill vent, or mechanical damage will cause zero shift in a mechanical pressure gauge. The solution to a clogged liquid-fill vent is to fix the vent. Overpressuring a mechanical gauge to the point of permanent...

>the receiver, and the converter are the slave device. The reader is the Master. Hopefully that's the case. Only one master is allowed on a serial Modbus network. Typically field devices and output modules are slaves. >the slave devices should be connected to the Master port or to the...

Let me restate the data path from sensor in the field to the analog output, to see if I got this right: sensor > wireless xmtr > wireless receiver (Modbus/RTU/ASCII slave) > Reader (Modbus/RTU/ASCII Master with ethernet something-or-other) > converter (Modbus/RTU/ASCII slave) with 4-20mA...

A manual for the Conzerv EM3460 is at http://tinyurl.com/ajjfxlv Page 53 has whatever limited information is provided on their Modbus RTU implementation. Their table lists only 7 variables available via Modbus, starting with KW at 3003 PF at 3007 V at 3009 A at 3013 kWh at 3123...

I'm not convinced it's fluid dynamics, but who knows? 1.>A strange dynamic has occurred causing the level in the stillwell to change by as much as a foot. >is causing the water to draw down within the stillwell, giving a false level reading. If the actual level is truly changing then a...

I'm not sure which document you were reading, but other ultrasonic vendors do not do it in that fashion. > The sensors are then scanned in sequence. I would interpret that statement as multiple transducers are not fired simultaneously, but in sequence, one after another. Since the same...

Synch is for - transducers installed in the same tank/bin or - when the cables from the electronics box to the transducers run in parallel even when transducers are in separate tank/bin

Google is your friend. The manual is your friend. Page 16, FMU manual 45564377: Synchronisation line In order to avoid cross-talk between parallel routed sensor lines connect the transmitters max. 20) to a synchronisation line. The sensors are then scanned in sequence. If more devices...

What technology is the transmitter? Located where,physically? CO2 Line temperature?

I've used various ultrasonic open channel flowmeters that use ultrasonic transducers from Milltronics/Siemens over the years. Foam can throw off the level/flow readings of ultrasonics, as can dead animals, tree limbs and various storm sewer debris. But, it does work...

The question is posed as if a PLC were a printer, where one downloads a driver (for a particular PC operating system) to make a connection to the printer. But PLC's are not printers. If by "I/O driver", you mean you need software to get data from the PLCs into a PC for viewing, archiving...

HART needs a minimum of 230 ohms in the loop. An analog input (AI) supplies some resistance, but the value varies from manufacturer to manufacturer. If that A-B AI uses, say 100 ohms, then you need more resistance in series in the loop, but not across the (+)/(-) of the AI. There's a...

Interesting, I read the original post and for the life of me I couldn't think of how one would burn up an A/I input resistor because I mentally assumed correct polarity. But a power supply's voltage across a diode and a 1/4 watt input resistor? I can smell the smoke. I should know better by...

PID requires frequent 'on-off switching' of the electrical power to the heating elements. An on-off control signal from the temperature controller to an electromechanical or solid state switch is used. The more frequently the heater can be turned on or off, the closer one can get to...