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lonegator

Cables Needed When There's NO 8 Pin Serial Port

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Hello All. I'm the IT Manager here and need to purchase some new laptops for our Service/Engineering department. I'm trying to convince our guys that they can do what they need to do without the serial port but am receiving a lot of flack. Can someone list out all the cables needed when connecting thru a USB port? We deal mostly with MicroLogix and ControlLogix. Also, though I'm in the A-B forum, I haven't investigated this too heavily yet but assume that USB conversion cables are available for the other brand name PLCs and drives. Is that correct? I purchased a USB 1747-CP3 and a 1761-CBL-PM02 and tried to connect to a ML 1200 but didn't have any success. Could someone also list out the steps to successfully connect using these cables? Thanks for your assistance. Doug

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I have a Keyspan usb to serial adapter that works with my micrologix family of PLC's. I also have a usb (1747-UIC )adapter that lets you hook up RS-232 or DH-485.

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As he said, a USB to Serial adapter should suffice, but some older programs I've seen don't work well with them.

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I apologize up front. I am on the service guys side. Our company just changed the standard laptop to a Dell Latitude D630. It has a serial port. I immediately requested an upgrade from our old HPs without a serial port. Some of the software requires the port number to be comm 4 or less, some will only work with comm 1. The USB to serial converters usually pick an random comm # between 5 -8. Some software wants the same comm number each time. Not all USB to serial converters are equal. In other words, life is so much easier when you don't have to worry if your comm port is working? I will always prefer a comm port over a USB to comm port converter.

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I've had a video out for awhile, I just tried to edit or add a commentary not long ago, trying something new, but this is the same step by step on how you would connect to a ML1200 with a PM02 cable: http://www.mrplc.com/kb/index.php?article=83

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This is just my 2 cents worth, but I've yet to find a USB to serial cable that would allow you to connect to a PIC module. If you can get them one, get the serial port. It saves SO much time...

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Welcomw to the forum lonegator Not trying to give you any flack. Just want to make sure you realize what it MAY cost you or your company by NOT having a true serial port. I have most of the USB adapters that I need to talk to the the AB Family of PLCs. I have over $250 easy 1747-UIC just to talk to DH-485 , I bough the AB serial adapter another $100. That probably pays for the cost of a real port on a laptop. That does not even touch the old school devices that need power from the port to function. Since then I have replaced my laptop with a DELL Latitude D830 with a real port. Just my half a cent worth of advice. PS do your guys us a PCMK card for DH+ or Flash cards? PSS I just noticed that it said NO 8 pin. What connector are you using? A PC has a 9-pin D-shell Edited by JAK

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I use a Belkin USB to serial converter for our micrologix and SLCs it also has worked fine for the ultra drives

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I meant 9 pin... My dilemma is that our general manager doesn't see the need to fork out an additional $1,000 just to get a laptop with a serial port (when I've read on here that most of you never have any problems connection to MicroLogix processors which is mostly what we deal with). From what I can find, I'm going to pay at least $1,500 for a decent, new laptop with a serial port and on NewEgg right now, I can get a decent laptop w/o a serial port for $500. As hard as our service guys are on laptops here, that's much more cost effective and if the USB to serial adapters work sufficiently, we're going to have to go with the cheaper laptops. We have 4 older laptops that still work and have serial ports. If any of our service guys need to connect to something else and don't feel the USB to serial adapter will work, they can take one of the older laptops along as a backup.

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I have two laptops and I use the converters from Quatech. They are rock solid and I have not found anything that I cannot connect too serially. PCMCIA version http://www.quatech.com/catalog/rs232_pcmcia.php Express Card version (had to buy this when I found that my new laptop did not have a PCMCIA card) http://www.quatech.com/catalog/expresscard_performance.php I also have a devicenet PCMCIA card that I need to use occasionally. I bought a PCMCIA to express card converter by Duel Systems http://www.duel-systems.com/products/adapters.aspx what works well with my AB card. I wished manufactures of new equipment would put USB or ethernet ports on their equipment instead of serial ports. I still see this on recently released equipment on a regular basis. Giz

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We use the cards from quatech for all serial if the laptop did not have a serial port . They are not that expensive ,a hundred or so dollars. We went this direction six years ago because usb to serial was so hit or miss.Never could find one that worked everytime,as a field service person I need equiptment that works on the customers floor 400 miles away from the office.The cards work all the time .

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This is my opinion. I design and install/service equipment/machines and i have found that having the serial is a must. I don't know if your service guys use a varienty of different manufactures for plc, but you might want to consider that for future use. Other manufactures have to have a serial port. So you might want to think about other plc's, hmi's than just AB. If it were me i would pay the extra money to get the serial because that is what they are used to and they(service guys) know it is going to work. There is nothing more frustrating than using something new that says will work and you are sitting there pulling out your hair trying to make it work.

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Greetings lonegator You have said that you deal with mostly Micrologix and ControlLogix. You won't have any issues connecting to these with a USB/serial adaptor (Ethernet would be better and MLX and CLX are both available with ethernet). But, and its a big but, you used the word "mostly." With mostly correct info you will get a mostly correct answer, but that means that part of the answer could be flat wrong. All it takes is just one PLC that you can't connect to through the USB to serial adaptor and you could rapidly accrue expenses that will make the few hundred you saved on the laptop mere tears in the ocean. USB - serial adaptors cannot provide the rigid adherence to the IEEE RS232 standard that some devices require. So hopefully you will understand my concern over "mostly." To get the best advice, we need to know all the models they will be needing to communicate with.

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Greetings lonegator; Alaric makes an excellent point. I still have PC's running windows 3.11 in a couple of our machines. The strict adherence to IEEE RS232 Standards are necessary for certain old devices. Baring that I'd prefer PCMCIA Serial to USB. {and I don't mean the new express/compact pcmcia} Just an old dogs opinion.

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Hi, I would have to agree with most of the other guys. We had to get a new laptop in work recently because the old one's comm port was shot. I insisted that we get one with a comm port. My boss wasn't impressed, but we got the new one with a comm port. The following week we had a problem with a device and the only way to connect was via the comm port. My boss knew then it was money well spent. Also, I think someone else mentioned it, but I seem to have had problems with connecting through USB to a PIC. Anyway, comm port all the way Just my 2 cent

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