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HART communicators

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omby

Industrial
Jun 28, 2004
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Hi,

Can anyone reccomend a basic up to date HART field communicator for an industrial environment to connect to a stand alone transmitter for set up and calibration?

Fairly happy with the now discontinued Emerson 375 & 475's but the ones I've tried lately either dont have full set-up functions, are vastly over complicated with unwanted functions. or not made for human sized hands.

Thanks

omby
 
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Have you had experience with this model danw2? I was after something fairly basic and more at the cheaper end of the market.

Thanks

omby
 
Yes, I've had experience with it and its predecessor, the 4150 and with Pactware and PDM. Both Meriams were capable of executing HART instructions via the keyboard. No complaints with those features that I recall.

DD file updates
A 4150 problem was the need to eventually add a DD file. For the 4150, Meriam converted a HART DD file to their version: a DOF file. The 4150 could not use a HART Foundation DD, it had to be a DOF file. Meriam had a free Windows software program that manages the download and supplied the DOF database file for free. The 4150 updated through a serial RS-232 interface from a DOF database file supplied by Meriam. The 4150 could not update just one or two DOF files, it had to update the entire database, at serial communication rates that meant an update took 5-6 hours of communications, start-to-finish. After much frustration of several failed updates in a row, I discovered that the internal RS-232 COM port on the laptop being used just couldn't handle the stress and failed after 2 or 3 hours of continuous use (not Meriam's fault). Changing laptops fixed the problem and the update was completed.

The 5150 used Ethernet, I believe (the update I did was 4-5 years ago and it could have been Ethernet or USB, I'm foggy). It turns out that the Ethernet is generally more convenient, just plug in a CAT 5 cable, However, the database file transfer operates at serial comm rates. So, yeah it was an Ethernet cable, but it still took forever and a day to update the handheld.

The 2nd time I needed a DD file update on the 5150, I bought a programmed SD card from Meriam that had the entire DD database on it for something like $200 and spent all of 10 minutes plugging the SD card into the unit. Although Meriam doesn't advertise that approach as a standard upgrade path, I'd buy the SD card again if I needed an update and be done with it.

Batteries
The 4150 used disposable AA batteries. I liked disposables, the other guys liked disposables. Took all of 4 minutes to unscrew the battery cover, replace the batteries and you're up and running.

The 5150 uses a rechargeable lithium battery. Decent battery life, but you're back to putting the unit in the charger stand and if the job is off-site, dragging the charger around, just-in-case.

I have a vague recollection of needing to add a single DD file, but I can't recall whether it was to the Meriam 5150 or to Pactware, so I'm unsure of whether the 5150 takes a single DD file upgrade.

Pactware
Pactware is Windows software that uses DTM files and uses a USB/HART modem to communicate with HART devices. Pactware will definitely take a single DTM file update. Pactware worked OK for my tasks, none of which involved hazardous areas (Windows laptops are not suitable for hazardous areas). I ran the Krohne version of Pactware. Just be aware that not every manufacturer supplies a DTM file for their HART device. There's little support for Pactware unless you're a customer of one of the Pactware providers. But it works and its cheap, no license for Pactware and the cost of a USB HART modem.

USB HART converters
The price on USB HART modems has dropped over time, but I'm still leery of anything cheap from China. The company used quality Mactek USB HART converters. I suspect Procomsol makes a quality modem. Mactek supplied a Windows utility app that would check the HART connection by polling for the primary variable at one second intervals and displaying the value. That was really valuable, confirming that the modem had a connection to the field device.

Siemens PDM software
What a monstrosity. Installation took 4-5 hours with 2 or 3 CD ROMs. It needed a crippled version of Step 7 software to operate so installation included Step 7. What a memory hog.

The best feature was (past tense) called "Life list", which with a single click would find and report a connection to single field instrument connected point-to-point on HART address 0 and display its tag name. As opposed to a 15 click task of opening and building a project to get a HART connection. Life List appeared in, say, Version 5. The convenience factor was too great for ordinary mortals so the Siemens gods stripped it out of the subsequent versions. Very Teutonic. If you can't do it the hard way, you can't do it at all with Siemens. I hate PDM. Numerous times getting the connection to the field device was more magic than science. Cryptic error messages, screen after screen. I suspect that HART had some published spec on timing that Siemens interpreted to the nanosecond, whereas everyone else would allow for a little tolerance, because I didn't see those connection problems with Pactware or the Meriam. Single license version had to turned off and then back on to use it for a 2nd connection to a different device. Single point license version cost less $100 when I was using it (4-5 years ago) but if your PC crashed you lost that license. Siemens would never replace single point license, you had to repurchase. I was told Siemens would replace multipoint licenses, but I only ever used the single point license version. PDM is good choice for the masochist who needs a HART master.
 
Cheers for that danw2. I'll look into the Meriams...
Agree with disposable batteries, it makes life easier, and have had minimal experience of Pactware which seemed - as you state - a lot of effort to interrogate transmitters not previously saved.
 
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