Search results

1) The manual is clear that DTE must be held high: "For the meter to identify an RS232 connection from an outside source, and to keep the RS232 hardware active once communicating, the Data Terminal Equipment (DTE) must assert and hold high the DTR line of the DB9 connector (DSR of meter)."...

Connect the +12V to DTR.

1) would he expect the gateway/device to act as master or slave? A gateway has 2 sides. The Modbus side would be a Modbus RTU slave or a Modbus/TCP server to outside world. The other side communicates to the ventilation unit. A Modbus master/client reads or writes data to the...

Did this PLC/SCADA combination ever work properly? SCADA is reading some kind of register in the PLC to get its data. Is there a separate comm card which SCADA reads from? Could that be the problem? I have seen a Modbus slave device put spurious (random and erroneous) high numbers...

I suspect your problem is a ground loop caused by the powered digital display. If you can substitute a 'loop powered' digital display for a powered display, you might get a working circuit without an isolator, because a loop powered digital display is 'floating'. To use an isolator, your...

You're asking for a dual instrument Tri-Loop, aka Hex-Looper(?), that would have to integrate - HART master functionality - Multidrop functionality (single pair of wires to multidrop both field transmitters) - break-out analog box functionality to get data into analog form on the host...

Who knows? That kind of published data is hard to find. But I seriously doubt that a PLC CPU is injecting bogus data values when AIs are known to have problems with common mode or noise coming in from the field, or a bit or two in the AI card's A/D are failing. You need to troubleshoot...

> HART device will only respond to an incoming HART request. Correct. HART is a master/slave protocol and the field transmitters are slaves who wait for an instruction from a master. The analog input spec sheet for the 404 does not include the word HART, so the AI card is not a HART...

First time I've heard that and I don't believe the explanation. 99% of industrial analog inputs are not HART pass through inputs that are looking for the HART signal. Industrial analog inputs (as opposed to an oscilloscope test & measurement input) 'see' the DC 4-20mA signal but not the HART...

Page 6, pdf http://www2.spiraxsarco.com/pdfs/sb/s66_11.pdf

This is very likely a Eurotherm software/firmware issue. Eurotherm has its own Schneider sponsored 'community-powered support' forum where the green banner in the corner says "Eurotherm employees are here to help" which is not always the case with company hosted fora. Since there hasn't...

Possibilties: 1) Field signal has a ground loop which adds some current that the DCS analog input (AI) sees. This problem can be masked when a check of the AI is done with a battery powered, floating signal source and it shows everything is fine because a battery powered simulator...

Maybe you could clarify. If you connect the FF cable from DCS FF card to the Valve coupler and then extend the FF cable to the MOV, it infers that the MOV has a FF positioner. If the MOV has an FF positioner, what is the purpose of the coupler? What is the coupler supposed to do that an...

There is a high likelihood that the CS3000 is an OPC client which can talk to an OPC server whose 'driver' can, in turn, can talk to the SCADA via some protocol. You'll need to find out what protocol the SCADA can talk and whether the CS3000 is an OPC client. Then go shopping for an OPC...

The parameters that an analog/HART DP flow transmitter needs to know are: - the engineering units for DP: inches of H2O or mm of H2O - the DP value created at the maximum flow rate for the design conditions specified for the primary flow element the DP transmitter is to be used with. This...

Micro Motion's troubleshooting guides are typically in the converter/transmitter/electronics manual, not in the coriolis tube manuals. For instance the 1700 transmitter has 43 pages in its troubleshooting section. A cause of a change in reported density is coating in the tube. Go get...

http://tinyurl.com/n6xs292 4-20mA input runs a motorized potentiometer output.

A Samson 6109 is an I/P. An I/P converts a 4-20mA control signal to a pneumatic control signal. The pneumatic output typically becomes a control input signal to a pneumatic positioner. A Samson 4763 is an electropneumatic positioner. An electromechanical positioner uses an electronic 4-20mA...

Thank you for the follow-up report. It's rare that the forum hears about a success or a failure.

There's no single transducer I'm aware of. Any signal conditioner vendor has an isolated 'high voltage' (it's all relative') DC-to-4-20mA module. http://api-usa.com/pdf/api/api4380ghv3.pdf As far as I know, conversion from analog to Fiber Optic (FO) is a separate function. Weed...