Archive for category Troubleshooting
Written by: Dan Weise
I couldn’t communicate with a HART device. The configuration software I was using, Pactware, thought the USB HART modem was on COM 3, while Windows’ Device Manager showed it was actually on COM 6.
To change the COM port in Pactware to COM 6, I right clicked COM 3 and selected Parameter:
Written by: Dan Weise
I’ve used Pactware for a couple years now, so I was surprised when I couldn’t get the Siemens LUT400 to work with the software. The LUT400 ultrasonic level and flow controller comes with a DTM file that I installed before opening the Pactware software.
The DTM file can be downloaded from this link: http://tinyurl.com/cqk2cky
Once it had been installed, I opened Pactware and updated the device catalog, as seen in the picture below:
But when I attempted to establish a HART connection to the LUT400, I got an error message:
Written by: A.J. Piskor
One of the key pieces of any combustion system are the safety shutoff valves. Their job is important, stop the fuel from entering the system when requested or when a fault is detected. With the harsh operating environments and demanding cycling that these valves sometimes go through, internal components have been known to fail. Not only does this bring the shutoff valve down (to a safe position), but it also brings down the combustion system with it.
Maxon shutoff valves are known for their performance, reliability, and durability. In the rare case that one of their automatic reset gas valves (Series 5000/SMA11 or 5000CP/CMA11 for normally closed models, series STOA/SMA21 or STOACP/CMA21 for normally open models) fails to perform, it’s possible that one of the internal components could have gone bad. Each Maxon automatic reset shutoff valve comes with three critical electrical components (solenoid, motor, position switch) that need to work together for the valve to operate properly. By listening to the valve cycle to its energized state, you can detect if any of these critical electrical components needs to be replaced.
When their Remote View option is turned on, Trendview paperless recorders display recorder screens in Internet Explorer as shown here:
Getting a printout was not as easy as using file > print, because the technology uses Active-X components in Windows, so the result is a blank screen; something to do with Active X and printing.
Everyone agrees that it’s good practice to keep a record of configurations and setups for any field instrument. I’m constantly recommending it to our customers for their transmitters, controllers, recorders, and other complex configurable devices.
Siemens clamp-on ultrasonic flowmeters even have a system in place to make this process easy. By connecting the meter to a PC through the RS-232 serial port, you can use a terminal program and the SITE command to fetch a data file that holds all the instrument’s configuration data.
The terminal program can also be used — with a set of instructions specific to the flowmeter — for viewing real-time operational data, performing device setup, uploading logger data, or uploading configurations known as SITE setups.
Recently, I was called to visit a plant and look at a misbehaving flowmeter. From previous discussions with the operator, I knew he’d saved SITE setup files for every flowmeter installed in the plant.
I asked if the customer would e-mail me the setup file before my visit, so I could check out how the flowmeter was set up. My request was met with a chuckle and “Well, if you really think it’s worth it…”
Recently, we’ve run into a few radar level applications that had some startup challenges, mostly because the person installing the transmitter didn’t consider how radar wave transmission would affect the level transmitter’s performance.
One trick to any installation is to reduce the number of obstructions encountered by the transmitter. But you have to take into consideration that radar waves don’t transmit in a concentric circle around the transmitter. And this can create a problem of its own.
A while ago, I got a call from a customer who was having trouble with a differential pressure transmitter. He was using a draft range DP transmitter to measure the pressure in a combustion chamber, so it could be controlled with a damper. He had one port connected to the combustion chamber with impulse tubing, and the other (low side) was left open to the atmosphere.
He’d noticed that when a fork truck or other vehicle sped past the furnace – the transmitter was mounted next to a traffic lane — it cause the furnace pressure to momentarily dip downward, and cause the damper to oscillate.
He figured out that the air movement provided by the passing vehicle was creating a momentary pressure pulse on the low side port. These air movements were creating difficulty in maintaining furnace pressure.
So, he asked me, “How can we dampen the effect of the momentary pressure pulse?”