Hi, all. I am in need of some help. I work for a large company as a project electrician. I have been training for the past year or so with the Automation Controls Manager with this company to become is eventual replacement, five or six years down the road. He has been diagnosed with lung cancer and is no longer able to work. So, for the short term, at least, I've been put in charge of writing and maintaining the programming. I understand ladder logic and am not having a problem with writing the programs or their various functions (although PID did give me quite a headache). My problem now is that we have a major project in which we'll be demo'ing an existing Switch Gear room. The old switch gear room had 17 starters in there, which will be relocated to a brand new switch gear room. These 17 motors currently exist in the program, on a 1746-A10, being controlled by a 1747-SLC5/05. In slot one of the local base, there is a 1747-SN. That feeds three remote bases (logical base 0, 1, and 2). I will be adding another ASB to the local base, for a 1746-A7. Originally, I had planned to just series it into the existing SN card, but I have an issue with that. If I series into the existing SN, I will not be able to expand off of that rack, in the future. My line of thinking is, if I do end up needing more input/output (currently, the seven slot rack will have 10 spare discrete inputs and output points, but no spare analog), I'd have to add a SN card anyway and feed another blue hose. In my local rack, I have a blank in slot 2. I am considering placing a 1747-SN there, and letting it be the feed for this new A7. My questions are: 1- Are there any issues to look out for, when it comes to adding a second SN card to a base? 2- How would I go about mapping the G-File for this? I am using one slot addressing. I would have the first rack start at Logical Group 0, Slot 0, and take up 6 groups (I think), but what if I wanted a 13 slot rack instead? How would you configure that with the G-File? The documentation I have is only furthering my confusion. I apologize if I've made this too confusing or have rambled unnecessarily. I'm in a "crunch" mode (the changes are slotted to be in effect by the end of this month) and I wasn't expecting to have to do this program until two days ago. I've gotten the programming changes made easily enough, substituting tags. I've done my BTR and BTW for my analog inputs and outputs. I just want to make sure my memory map is correct, as that is most likely what's going to hang me up the most (other than building my bricks and changing my wonderware). Any clarification I need to make or postings I need to do, let me know, and I'll do my best. I really appreciate any help. Long time lurker, first time poster. EDIT: For reference of my experience, in case that helps, I've written around twenty programs for this company. All have been for wastewater applications, either SLC5/05 or SLC5/04 processors used, and all have been A13 racks with a connecting cable to another A13 racks. The layouts on all panels and programs have been different, due to different rendering methods at each location. This is just the first time I've ever had to mess with remote bases and addressing those.
