Products > Test Equipment
please dont purchase PC controlled test equipment
alm:
--- Quote from: Wolfgang on March 05, 2023, 11:16:42 pm ---The problem is not that a piece of equipment is only controllable by a PC, the problem occurs when this control is not done in a standard way like SCPI and special, soon outdated software is used. Then I agree, never buy this.
--- End quote ---
How many commercially available instruments that rely on PC control use SCPI for communication? I doubt you'll find many. Can you name a PC-controlled oscilloscope that talks SCPI to the host PC over a standard protocol like USBTMC? Or a logic analyzer? Or a function generator? Some VXI cards maybe?
--- Quote from: Wolfgang on March 05, 2023, 11:16:42 pm ---On the other hand, a lot of stuff used in automation will never be operated by hand once the programming is done. This means you dont need a screen, a keyboard, switches, ... all that stuff. What I do is using standard lab equipment (DMMs, generators, scopes, whatnot) during the design phase, and then I make special appliances that are SCPI controlled to do the automated stuff. With an Arduino its possible to make quite smart stuff that costs only a fraction of all the fancy gear with GUIs. That works great and its fun.
--- End quote ---
HP used to offer some equipment without front panel to be used only by GPIB control. It would not surprise me if that is still possible. But in general I highly doubt that removing the front panel is going to have that much impact on the BOM costs for anything but a very basic device like a simple bench power supply. How much of your saving is because the lack of front panel, and how much is because it's designed for a single purpose, less margins, less overhead, less compliance testing, etc? Modern front panels are using fewer mechanical switches and no expensive multi-turn pots, so if anything front panels are getting cheaper.
If you compare say an NI offering for a USB/PXI card to a bench instrument, then I doubt you'll be much cheaper. And good luck using it when NI stops supporting the device for newer OS versions or CPU architectures (x86 -> ARM). Their main advantage is density in a commercial production environment.
jasonRF:
--- Quote from: oz2cpu on March 02, 2023, 12:39:53 pm ---Headline : please don't purchase PC controlled test equipment
I mean of course ONLY controllable by pc
It is really driving me nuts, as a collector of funny old test equipment,
every time some stuff is controlled only by a pc, and a bit old,
it is impossible to get software, drivers, support
and operating systems changed 4 versions since...
this means such stuff (pc only control equipment)
come with a very short expected lifetime,
some of it is even just as expensive as real standalone equipment with remote capabilities,
this means in many years when the remote features are no more supported
you still have a working standalone unit, and not trash.
--- End quote ---
I believe everyone should buy the equipment that is best suited for their needs. For some people and some needs that will include equipment with PC-only control, while for others it will not.
Not long ago I had to be on travel and of course brought my laptop as always. But I also wanted to bring a scope and packed a USB model with PC-only control. It took virtually no space and weighed nothing. Had I instead tried to bring a bench scope, I would have had to pack it to survive commercial air travel, and since I did not have room in my carry-on bag would have had to check a bag which would have meant an extra fee. Are you really saying that someone who must travel like this often should never buy a usb scope, and instead lug around clunky bench scope and pay an extra baggage fee on many flights just so you can pick up the old bench scope in 20 years and make it work? And even if the usb scope is junk sooner than the bench scope (not clear if you are traveling with it all the time), how many usb scopes can you throw out before you have generated the same amount of trash as one bench scope?
jason
JPortici:
--- Quote from: 2N3055 on March 04, 2023, 11:52:11 am ---
--- Quote from: james_s on March 03, 2023, 11:43:39 pm ---
--- Quote from: TomKatt on March 03, 2023, 11:08:28 am ---Yes, we did. While we also have equipment using industrial pc hardware like you describe, this unit was some oddball custom 386 base pc with MS Mobile Embedded in ROM on the board. We even sent it out to a repair shop that claimed they could repair it (they have done many other repairs for us) and they couldn't resolve it either. I'm sure from a technical pov it wouldn't be too hard to replace it with some generic pc system as the actual IO is run by PLC's in the cabinet, but apparently the manufacturer did not have any generic software that would interface with the PLC system as that software was all in the ROM. So their solution was $40K+ to replace everything when the saw went for around $60K on the used market.
--- End quote ---
Well that's annoying. It illustrates the issue with equipment that should last many decades relying on computer technology that becomes obsolete after just a few years.
--- End quote ---
First of all, what manufacturer is claiming a CNC machine will last 25 years? Or a scope?.
They are very good if they provide any support more than 7 years after it was stopped being produced.
This is a good example how it would be better if they made a machine run on off the shelf DELL PC for which you could find replacement. But they used custom MB, so only course of action is that manufacturer should stock hundreds of spare motherboards for repair of machines in supported period.. Which they don't..
As I said, people can like or not PC based T&M equipment based on preferences or use case, but reparability is actually slightly better than for fully custom hardware.
--- End quote ---
It's not uncommon at all. Industrial machinery can cost tens to hundreds of thousands and is build to a certain degree of quality. Ten years ago when i dabbled in internships in that area it was no strange to find machinery with windows 3.11 PCs controlling them. The idea of scrapping a perfectly good (and costly) machine because the computer is outdated is ridiculous, but that means that you have to be able to keep the old pc running
Wolfgang:
Disagree again.
Almost all "renowned" manufacturers offer SCPI-enabled instruments.
For DMMs: Keysight/HP/Agilent, Rohde&Schwarz, Siglent, Rigol, Keithley, Tektronix, ...
For Scopes: Keysight/HP/Agilent, Rohde&Schwarz, Siglent, Rigol, Keithley, Tektronix, LeCroy, ...
For Signal Generators: Keysight/HP/Agilent, Rohde&Schwarz, Siglent, Rigol, Keithley, Tektronix, ...
list may be continued. All of them now offer remote-only instruments. The market is clearly automated testing
in a factory environment, and this market is huge. Here you need the max of test functionality in a cramped space. All this PXI stuff is just doing that.
horo:
--- Quote from: oz2cpu on March 02, 2023, 12:39:53 pm ---Headline : please don't purchase PC controlled test equipment
I mean of course ONLY controllable by pc
It is really driving me nuts, as a collector of funny old test equipment,
every time some stuff is controlled only by a pc, and a bit old,
it is impossible to get software, drivers, support
and operating systems changed 4 versions since...
this means such stuff (pc only control equipment)
come with a very short expected lifetime,
some of it is even just as expensive as real standalone equipment with remote capabilities,
this means in many years when the remote features are no more supported
you still have a working standalone unit, and not trash.
--- End quote ---
Here, open source (OS), open firmware (OF) together with open schematics (OSch) would give your devices an eternal life.
One example I maintain is the >10 year old Hantek6022 DSO -> OpenHantek6022 (OS, OF, OSch).
Other examples are tinySA (OS, OF) and NanoVNA (OS, OF, OSch).
And if you are willing to give up Windows in your lab, then you can stop the artificial software rot, Linux supports old parallel port devices as well as historical GPIB and SCSI interfaces right out of the box.
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