Shad

No idea what this is worth, Ive checked Ebay but the prices are all over the place. Just wondering if anyone here might have an idea of what this might be worth or if there is a market for it. Specifications are as follows: Allen Bradley SLC 500 7 slot rack: 1746-A7 ser A Power Supply: 1746-P2 ser A Processor 5/01: 1747-L514 ser B 4 slot rack: 1746-A4 ser A Power Supply: 1746-P1 ser A Rack Interconnect Cable: 1746-C9 ser A Input 115 VAC: 1746-IA16 ser B Input DC Sink: 1746-IB16 ser B (have 2 of these) Input DC Sink: 1746-IB32 ser A Input / Output Analog: 1746-NIO4V ser A Output DC Sink: 1746-OV32 ser A Output DC Sink: 1746-OV16 ser B Output Relay: 1746-OW16 ser B Card Slot Filler: 1746-N2 (have 2 of these) Everything appears intact and these parts have no apparent damage. Unfortunately I have no way of testing anything here at home. I got this unit several years ago while doing a rebuild on a machine and it was in working order when removed. If you have any ideas please let me know Im tired of it collecting dust at my house at any rate.

OK I did manage to solve this problem but I doubt I took the easiest route to do it. I used an MWIR command to move STW142 into C1 through C16 then I used a second MWIR command to move STW143 into C17 through C32. By isolating each bit I could assign their values to individual contacts and use series (AND Logic) circuits to get the desired result. Now as I said I doubt this is the easiest means to an end but I just couldnt figure out a way to get real time out of the status words the way they are arranged. If there is an easier way to create a real time based event trigger using status words or otherwise I would still be interested in your solutions.

Im more familiar with AB programming so this may seem like a silly question but here it is anyway. I know status words 141-144 contain the PLC date/time settings but Im not sure how to utilize this in a real world situation. For instance I want an event to trigger at 3:00 PM each day and STW142 contains the hours (tenths and units) in its least significant byte and STW143 contains the minutes (tenths and units) in its most significant byte. Im not sure how to isolate the hours and minutes information to create a compare statement that I can use to trigger my event. Can anyone help me with this??

I dont mean to sound obvious here but has he contacted the installer/manufacturer of the heating system and asked for suggestions. Sounds to me like there were some real miscalculations at the very least in the design of his heating system. I used to be a residential builder and have some experience with various heating systems and that just sounds like an awful set up in my opinion. If Im correct you are talking about a hydronic system and yes those do tend to require longer cycles to create a comfortable environment and the large windows would complicate the demands on the system but that should have been taken into consideration during the install. I know this didnt directly answer your question but it might be a useful place to start if you havent already tried this.

Yeah that was kinda my impression as well (stripped down to be competitive) but the one I got and was about the same price as the Dell Latitude D800 I priced. The D800 being very comparable size as the Inspirion I purchased only close to $1000 more on the price tag. Im not a penny pincer but come on the systems being virtually the same I wouldnt expect that much of a difference in price for stronger hinges. Just to be clear my intention is not to specifically use the Inspirion for programming, Im taking 4 PLC courses this year at college while I teach some other courses in the maintenance program. Im gonna need a portable system to keep up with what I have going on and if I can also use that for programming its a huge bonus. I will also likely try to get CAD in there as well so I could potentially have a lot of programs on this machine, I expect that being MULTI-FUNCTIONAL is gonna be the key concern for me. I expect any programming I do will be strictly in a lab type atmosphere so some of the concerns just arent going to apply to me as much as a bona fide field technician. Oh and by the way I did opt for a 4 year warranty with the Inspirion as well with the Onsite service package. I gotta agree that is a very attractive option.

Ok I stand corrected on the Dell and no serial ports issue, they in fact do offer a serial port on the Latitude D series as mentioned. However at a substantial increase in price compared to the Inspirion with similar specs. Now when I called Dell to order mine maybe I just got someone who didnt quite understand my needs as I specifically asked if they had a system available with a serial port and I was told that they did not. Perhaps because I had mentioned that I was looking at the Inspirion line when I noticed the lack of that port. At any rate Ive made my decision and Ill see how the PCMCIA cards work out and since I have more than one function to fill as well as limited resources for purchasing the system Im hoping Ive made a reasonable comprimise that will fill my needs for this system. Thanks for all the responses guys and you can bet I will return to this forum with the results and any further questions I have.

Wow very nice Ariel. That system has just about everything I was looking for to be honest. I havent heard a lot about ACER systems though and until you just jogged my memory I wouldnt have even named them as a manufacturer. So long as the warranty is good and the company is gonna be around 5+ years from now I cant see as it would make a big difference what the name on it was from my point of view though. Oh and just an FYI after talking to the folks at Dell they didnt list a single laptop with a serial port in the current line, nor was it an option. Guess thats the way of things though. Im gonna try the converter route I guess and see how that all works out. Hopefully Ill be able to successfully interface with the SLC 500 I have stored in the barn so I can experiment on my own.

Yeah its easy to dream that the PLCs will eventually go to USB but the reality is that even """"IF""" they do there will still be plenty of older units in use that will confound and frustrate. With the small niche use for the dated serial port on PCs and Laptops Im certian that this is going to be an ongoing problem due the the cost and work involved in upgrading PLCs. Lets face it industry has a track record of "If its not broke, dont fix it", basically if that old SLC 500 is still doing its job then its gonna be there until it doesnt do its job. My main concern is that with the new technology in PC/Lap tops (read lack of serial port in this case) if I did decide to pick up an older laptop just to have an onboard serial port that eventually the manufacturers will just stop supporting it. Not to mention an older model would probably not stand up to all of the uses that I have in mind for my system. Ah well I ended up ordering a Dell Inspirion 1150 today (no serial port but Im gonna try to make due). I upgraded from the basic model and still stayed within a decent price range. Specs: 2.6 gig CPU, 15" monitor, XP Home, 512 MB ram, 32 MB graphics, CDRW/DVD, 40 gig HD, Wireless network and a 4 yr warranty/in home service plan. All for just under 1500.00 USD

Hadnt really thaught about the newer types of memory to be honest guys but it makes lots of sense now that you bring it up. Guess with an 80 Gig HD I just dont have to think about saving stuff to make room on my home PC so I havent explored options for it. Definately gonna check them out now, since I have had the same problems with floppies suddenly being OUT OF ORDER when I try to use them to retrieve data. As far as the PCMCIA card serial ports I have heard mixed results on those from the people in the field that I know. Last check all the guys I "used" to talk to were horrified at the thaught of a USB to serial adaptor and would use the PCMCIA route as a last resort. Has technology finally muted some of the concerns of either of these or is it just something that programmers are gonna have to accept with the new machines? Thanks for the advice so far, Ill check back later to see if anyone else has an opinion.

Hey all found this forum and wanted to do a quick check of what you all consider must haves for a Lap top to be a good choice for programming a variety of PLCs. I just took a new job at the local college teaching part time so I could go back to school myself and the first few classes Ill be taking are all PLC programming, probably throw in some CAD classes as well when I get time. I think its time to finally break down and buy a lap top for all those reasons as well as eventually programming. My personal choices in PCs usually require heavy doses of ram and HD space and at least moderate speed (thats 1.5 gig or higher in my book). Now all the new lap tops seem to have forgotten to put in a serial port and a floppy drive and from my experience those are pretty well must haves for interfacing with most PLCs and saving the small proggies. I know there are USB to Serial converters but the last I knew most of the techs that I spoke to really werent singing the praises of the converters. I have no problem with an external Floppy drive so long as it is rugged and effective, I just dont see a point in burning a CD to save a small program when a floppy will do. Bottom line is I want to be able to load up software to program various PLCs, possibly load up CAD, be able to have room for class work (both teaching them and taking them) and have a lap top that is rugged enough to take daily abuse of the job. Any idea whats working out there now, whats absolutely needed for interfacing these days, what kind of processor speed and ram. I dont want to make an uninformed decision and regret it later and possibly waste hundreds if not thousands of dollars in the process so any help would be most appreciated.