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I suspect that this was a small leak that developed into a bigger leak over time. If you want to find the small leaks so that you can fix or replace the seals/equipment, you can hunt for hydrogen leaks with a portable probe on a thermal conductivity gas detector/sniffer. The technology is...

If your 3610J pneumatic positioner has the bypass selector and you need to maintain bypass functionality, you might have to keep the I/P in service and add some valving, because smart positioners don't have a bypass selector switch. Sorry, I don't have cross-over data.

See my post, the last one, here: http://control.com/thread/1411750426#1411826356 Ignore the first sentence and start at "Modbus is a project. Congratulations, you're the project engineer!" The ABB flame sensor is a Modbus slave, substitute it for the word 'drive'. The HIMA must be a...

> any "tricks" for maximizing your sensitivity. Connect the low side to suction side of the blower and the high side to the pressure side of the blower. DP goes up substantially. You might have to test with an indicating DP transmitter (could be water tube manometer) to measure the DP...

As I understand it, the ultrasonic technology picks up 'scrapping' noise from solid material rubbing against metallic piping. Whether styrofoam generates that kind of noise, who knows? Doesn't the distributor/rep have a demo unit you can connect and see if there's sufficient signal to...

That isn't a very stiff 15V, is it? Use an externally powered repeater/isolator (4-20mA in/4-20mA out) that can drive the load, something like this: http://api-usa.com/pdf/api/apd4300.pdf Power that APD 4300D with 24Vdc and it'll drive a 1000 ohm load.

You need to know the minimum voltage the coil requires and its current load to calculate the voltage drop over that distance for your specific solenoid valve. On-line voltage drop calculator here (scroll down): http://www.electrician2.com/calculators/vd_calculatoradv.htm...

No, I don't have a Web300 so I have never connected one to a Modbus RTU slave. But the product line has been out there for some time and the 70 page "NiagaraAX-3.x Modbus Guide" (the one I downloaded is dated 2007) is a hefty read. Given the depth of its documentation, I have to believe that...

Are the two compartments are open across the top where the ultrasonic energy from one transducer could affect the other? If they are totally separate compartments walled off from each other, then that can't be a problem. Milltronics/Siemens ultrasonics uses a 'synch' connection between multiple...

> Whats the max length for Modbus over Smoke-Signal then please Depends on weather conditions, atmospheric conditions and time of day as do most proprietary protocols when they cease to operate reliably (who hasn't wanted to consult a medium when what used to work doesn't?) My comments...

I don't know what the ; means. Is that one byte at a time, each byte sent separately with some indeterminate pause in between? The message has to be one continuous stream of bits. Assuming the change in start address, the change in number of bytes, and change in CRC (from your earlier...

One would assume that a modern DCS would handle all four common formats, boolean, integer (signed or unsigned), 32 bit long integer, and the two common floating point formats and would do it without the need for conversion. Things are what they are, but it sounds like ABB covers those bases...

Although the Modbus standard does not define data formats, it is very, very common for Modbus to deal with 32 bit 'real' or 'floating point (FP)' values. The caveat is that the master needs to be able to interpret the 32 bit real or floating point values. Does yours? To my knowledge, the...

> carbon particles just settled and blocking the actual path between the sensor and flaming area. Dirt, oil or soot on the quartz (or special glass for UV transmission) lens of the UV sensor will attenuate (decrease, block) the UV passing through the lens. From the Honeywell text book...

GMI does not publicly post documentation, so it's an unknown. The ZXenta 511 claims Modbus master functionality, so it's probably capable. But, are these hazardous gas detectors? Logging historical data from a gas detector via Modbus is probably acceptable, but doing a hazardous gas alarm...

1) They are all "unsigned long integers": two Modbus registers or 4 bytes or 32 bits. You're sure you're looking at all 32 bits? 2) If your addressing is off by one, then you might be reading one register from long integer at 103Ch and one register from the long integer at 103Eh, which won't...

Hydrostatic level measurement by DP is only valid for a known density. Changes in density will be reflected as variations in head pressure with a resulting variation in level indication. In fact, DP can be used to indicate density when both the upper and lower ports/seals are entirely...

Modscan is a widely used 'test' master used to establish communication with a Modbus slave. My advice is that you really need to use Modscan or the other test master to establish communication with the drive from the PC so that you can see and understand what 'makes' a connection and even...

1) Profibus cable Profibus PA is not RS-485. Profibus DP is RS-485. I don't know whether Profi DP is full duplex or half duplex or whether a Profibus DP connector match your RS-232/485 converter is an unknown. You'll have to research the details. It could work, or might require a wiring...

No question that environmental protection is a major reason for hermetic sealing in general purpose switches. But hermetically sealed switches are used in Class 1, Div 2 (zone 2) because the hermetic sealing seals in any microswitch contact arcing/sparking is used to qualify for the...