USB to Serial (Good, Bad, Ugly?)

Hi All:

I've taken a new job where I need to purchase my own laptop. The company will help finanace an IBM T40 which has reviewed well but has no serial port. The tech guy asked if a USB to Serial adapter would work. That's a good question and I'm not familiar enough with the products I will be working with to know if that is a good idea or not.

The main PLC's I'll be working on are the Moeller ones. As specifications dictate, I could also be working on AB or other PLC's. Other devices will be Pacific Scientific Stepper/Servo Drives, Kollmorgen Servo Drives, Rexroth HNC servo hydraulic controller, IAI automation components.

I myself lean toward Dell (600m and 8600 Inspiron have regular serial ports built in) mostly for the complete care warranty as I have already had one laptop killed in the field and a warranty like that could have saved me! Does anyone know whether IBM has a similar warranty (basically, almost everything besides theft is covered,... even the dreaded spilled coffee in the keyboard ).

Thanks

nOrM

Look here - some info posted.
From my exprience some USB to serial adapters are not working good, some not supporting all features, some are not working at all.
All depends on your research and luck.
I found that some of these adapters are not using all handshaking lines or handshaking software is buggy.

Good thing about USB to serial that I can connect multiple devices same time and monitor them online without any problems.

I just recently completed project with Modicon Quantum and I used USB to serial adapters form www.plccables.com because my serial port used to monitor servo controller.
I also tried their USB to serial for AB and Mitsubishi FX without any problems.

Bad thing - no DOS support for USB to serial adapters - this is a major problem for controls guys.

It might be nice to make a list of what does/does not work with a USB to Serial adapter. I recently switched to a laptop with no serial port, so I got one of those cheap Belkin F5U409 USB to Serial adapters for the time being...

So far, I can confirm that it DOES work with the following:

Automation Direct (Koyo) DL06, DL205
Automation Direct EZ-Text and EZ-Touch panels
Maple Systems HMI500 Series Touchscreens
PacSci PD2400 Stepper Drives
Kollmorgen ServoStar CD Servo Drives

I can confirm that it does NOT work with the following:

A-B 1747-PIC (which we all know by now)
Mitsubishi FX1S through an SC-09 adapter (at least not for me)

Hopefully others will add to this list (including what brand adapter)

I am anxious to see if the RS-232 port on the 1747-UIC adapter from A-B will function more like an on-board serial port when used with other (brand) devices.

Now, the trick will be how to use one in a DOS environment!...

beerchug

-Eric

From my recent trials and tribulations attempting to use a new laptop designed for WinXP...PUSH hard for the Dell, attempt to get one NOT designed for XP...ie has drivers for Win2k and/or 98. Definitely attempt to get the serial port built in...a TRUE UART serial port.

Technology is definitely in a transition period, industrial automation is behind computer technology. It is catching up fast but not fast enough in many cases.

What can bite ya in the arse is the "I didnt know I would need that" factor. I am sure many will disagree with much of what I say because they now use XP and USB or PCMCIA adapters which does work with many plc's these days.
BUT
What happens when you want to connect to an older device, or run a dos based program...this is a legitimate concern.

I am not an Engineer BUT I strive to think the way I believe an Engineer is trained too. What IF should be a first thought to me, WHAT MORE can be should be right up there. You MUST weigh all the probabilities with the possibilities.

I just noticed you snuck in before me, Contr_Conn...

Since you were sucessful in FX communications, I should add that I'm using GX Developer - FX version 5.00...

beerchug

-Eric

The pacific scientific stuff is a dos program, Well, I should say that is all I have to transfer programs.

Get the serial if you can.

I just noticed you snuck in before me, Contr_Conn...

Click to expand...

Sorry, I was waithing paitiently for you to post, but my post came before yours
I am probably typing faster because I am making more mistakes...

Speaking of FX, I have GX-Developer 7.01, about 2 years old. I got it for CNC project, using since - it supports all my PLCs
Bad thing about GX - it supports ports 1-10 and COM driver can be set from 1 to 255 - just a small limitation.
I also tested FX-USB with MS-Component communication setup and test - really quick test.

Like I said before, I can connect PC to 3 FX plcs same time, using just a simple USB HUB.

BTW, I heard that PCMCIA-to-serial adapter port is a real port and may support DOS

I've used an RS232 to USB convertor from WIRETEK and found that it seems to work quite well with a nuumber of software packages. It also reasonably priced. I'm running Win 2000 and would u believe that I ran a bit of old dos software communnicating via this virtual com 2 port.

A mate of mine had problems with AB software using a PIC. He had to buy a PCMCIA RS232 adaptor to get it to work.

Well thats my 2.5cents worth

Mike Williams said:

The pacific scientific stuff is a dos program, Well, I should say that is all I have to transfer programs.

Click to expand...

I use ToolPAC for the 2400 stepper drives, which is a FREE DOWNLOAD if you're interested.

beerchug

-Eric

May be good to buy an old, cheap pentium or 486 from out of the local paper.
These are usually cheap, and you can run all your old DOS based programming software.
Just make sure everything you get with it is licenced and that you have the original disks for the operating system.

Doug

Eric,

Thanks for the link

These have been found to work or not work (as indicated) with Automation Direct PLC's. In my experience most are ok and will work with most devices depending on how strict the device is with timing.


Automation Direct USB-RS232 (Win98, WinME, Win2K, WinXP).
Belkin F5U103 USB-to-Serial adapter (Win98, WinME, WinNT, Win2K, WinXP).
Belkin F5U105 USB-to-Serial adapter.
Belkin F5U109 PDA adapter (Win98, WinME, WinNT, Win2K, WinXP).
Belkin F5U409-CU (works but incompatible with Toshiba 5005 laptop).
Keyspan USA-19QW (WinXP).
Digi AccelePort USB 2 two-port adapter (Win98, WinME).
Xircom PGSDB9 USB-to-Serial adapter (Win98, WinME).
Prolific (WinXP).
Targus (DOES NOT WORK!)
Quatech (DOES NOT WORK!)

I had the same problem when I got a new Compaq laptop which they call legacy free. I got mixed results with USB to serial adapters (and this was with moeller plc). I got a PCMIA to serial adapter at Frys for around $155.00US and have had no problems since with both drives and several plcs. Of course if I had it to do again I would make sure the laptop had a serial port.

Thanks to all who replied. The specific device references should go in a database somewhere.

I ended up ordering the Dell 8600 today. After comparing what all was included (or not included) with the IBM, it became a no brainer... especially after the talk here of people's preference for the 'real' serial port.

Now there is just the waiting and waiting and....

I have had no problems with the Wiretek device to Omron PLCs with CX-Programmer. Have had an occassional dropout with Syswin but not serious. Have also been successful with GX to a Mitsubishi A series PLC. Have also communicated OK to a Hitachi shoebox with Actwin without problems.
I am using a HP laptop with XP Home.
Have had absolutely no luck with GE Logicmaster 90 in a DOS box and a USB/serial converter. Obtained an NEC with a real serial port and Logicmaster 90 runs OK in an XP DOS box.
Have found the HPs really tough and reliable over the years. The NEC has a faster processor, more memory and is slower. Shame HP now only seem to be selling Compaq laptops. I have found them to be shockers over the years - compatability problems the lot.
beerchug