The HART communication protocol has been firmly established as the standard means of configuring field instruments for some years. But talking to a field instrument needs a communicator.
There are the handheld communicators, Rosemount’s x75s and the “budget-priced” Meriam MFC 4150, but at a cost that’s more a capital appropriation than an MRO expense. Even the Meriam, with a 3-year field device description subscription starts at more than $4000.
People continue to ask me if there isn’t a more budget conscious approach to HART configuration.
If you’re using ST3000 100 series transmitters, you’ll be looking at the ST800 for future units. If you’re using the ST3000 900 series, the ST700 will be your better fit.
When you’re making programming changes to a field device, you don’t always have time to wait. Here’s a hidden feature that helps you speed up the process between Siemens SIMATIC PDM and HART field instruments.
Normally, when you’re using PDM software, it takes a minute or so to upload or download changes to and from your HART devices. Seems like an eternity when all you need to do is change a range.
So, I’m going to let you in on a feature you might not have seen before.
RTDs are great temperature sensors – accurate and easy to install. But they are not friendly when it comes to trying to get a single RTD to go to two places, like when an RTD temperature measurement has to go to both a controller and a recorder. People call and ask, “How do I split an RTD signal?” The short answer is, “You can’t.”
An RTD cannot be wired in parallel or in series to a second device. Any RTD input supplies a known, regulated ‘excitation’ current to the RTD. Mixing RTD inputs would mix currents and that’s a Big No-No.
There’s also a lead wire compensation circuit for 3- or 4-wire RTDs that would create problems if a single RTD were connected to two different RTD inputs. There’s just no feasible means of making two RTD analog inputs play nice together.
But all is not lost. There are several ways to achieve your goal.
Part of my job as the technical specialist at Lesman is to make sense of new products and upgrades, and figure out what’s really going to matter most to our customers.
Sometimes it’s just a matter of a much-needed new functionality, or better configuration tools, easier mounting, or switching to the most current form of data storage.
In the case of Siemens’ latest ultrasonic controller, it’s all that and more.
Siemens (and Milltronics) ultrasonic controllers and transceivers, like the HydroRanger, MultiRanger, and OCM-III have been around for years with no significant improvements. Instead of updating these devices, Siemens has done a complete redesign, and introduces the SITRANS LUT400 as the first device in the new ultrasonic controller family.
Here are my initial thoughts on this new player in the ultrasonic game.
A customer who had had lots of experience with Milltronics and Siemens ultrasonics was installing his first SITRANS LR560 radar level transmitter. They had worked with it in the shop beforehand, going through most of the settings. They even tested it by setting it up to shoot against a file cabinet and used a tape measure the check the indicated distance value.
Everything checked out OK in the shop.
When they installed the transmitter on the top of the bin, they changed the transmitter’s sensor mode parameter from the distance mode they used in the shop for testing to level mode. After aiming, the level value shown in the local display was dead nuts on, but the 4-20mA signal going back to the control room was way off.
The bin was a third full. The 4-20mA showed it about double that. Not only that, the 4-20 was going in the wrong direction. The bin was emptying and the HMI reported an increasing level value. Someone realized that an inverse-acting output was typical of a distance value, so they reconfigured the sensor mode to distance. That got the 4-20mA much closer to a distance value, but it was still not exactly what it should be, and besides, the goal was to read level, not distance, in the control room. What was going on?
One of the strengths of Honeywell’s X-series paperless recorders is password security. You can configure it to keep operators from making configuration changes, and it’s a necessary part of being able to view a recorder’s data using a web browser.
One of the weaknesses of Honeywell’s X-series paperless recorders is password security. And by that, I don’t mean it’s bad. I just mean it can cause problems if a user fails to enter their username and password right, and ends up locked out of the recorder.
So I’m guessing if you searched for the backdoor password, you’re in that situation. You’re locked out of your recorder and can’t figure out how to get back in.
First, I apologize for luring you into reading this. There is NO backdoor password for an X-series recorder. But don’t give up hope: There is an answer.
(What’s a back door? Watch and learn.)
Hopefully, there’s a user at your location with administrator level access, who can reset a locked-out user. But if that’s not the case, what do you do when everyone is locked out of an X-series recorder?