Adding a 1747-SN module

[Pulsar2003 0]

Another project another headache!!! I have read some documents on AB's website concerning 1747 SN and ASB modules. In all the examples shown in the publications the SN module is on the Master rack just beside the CPU. Does the SN module has to be directly beside the CPU? Eventually I will most certainly need to add another rack to an existing system that uses a 552 cpu with a P4 power supply on a A13 rack. This is just added information should it be useful. Thank you again.

[fuzzy logic 0]

Absolutely not. You may have it inside any slot of the Processor's chassis. - fuzzy logic Edited 24 Jun 2011 by fuzzy logic

[Pulsar2003 0]

Great I was worried. This will definitely make is easier for me. I was worried that I would have to modify the inputs (as the IA16 are in the first 5 slots) physically and in the program. There is always a possibility of mistakes doing so!!! Thank you Fuzzy Logic.

[OkiePC 14]

Using search and replace with Move descriptions selected has been pretty foolproof for me when I have to relocate I/O in a program. You do this offline, then download. BUT, before you start, do a search for "[" without the quotes, and ensure that the affected addresses are not used in indirection. Then make sure cross referencing is enabled, open the data table and turn on the Usage monitor. Leave these movable windows on the screen while you perform the editing. Have two copies of the data table if they are in the same file (right click new window). Then you can visually see the descriptions moving from one data view to the other (highlight each one as you go). If you have to do this to a running system while moving one wire at a time, you can still use search and replace manually along with test edits and sometimes forces to prevent downtime, but if you use the windows clipboard, the F3 key (repeat search) it is much easier to avoid mistakes.Then it's F3, double click, CITRL+V, enter, repeat. You can accept each rung as you go around or make a second pass to turn ram rung edits into accepted edits. I leave my mouse pointer on the icons for accept rung, and use the HOME and CTRL+HOME keys extensively to control which programs I am searching/replacing online. For example, If you change the address of an OTE, you can't accept the rung until you highlight the rung, so press HOME to jump there, then left click the mouse. Then you rarely have to move the mouse, just click in rhythm with the lefthand on keyboard. Then make a final search by looking for "^a" (again, without the quotes) So, it's CTRL+F, ^a <enter> F3, repeat F3 until you have been through the entire program to see everything that will change when you press test. Putting block transfer modules adjacent to the CPU is probably a practice some prefer. I am not certain it makes any performance difference, but why send all that data 6 or 30 slots away to the SN module past foreign voltages if you don't have to? Plus, anyone who views the processor will see the scanner and immediately know that remote I/O exists. I like comm cards right next the modular SLC, followed by analogs, then DC, relays, then AC out at the ends...but that's just me. Edited 24 Jun 2011 by OkiePC

[Pulsar2003 0]

The main reason why I'd rather not change the way the inputs (from slot 1 to 6) are set is simply because of a pattern in which they were created. There is some logic there (for once on that machine). Not only would I have to move them physically there is the wiring (all is properly tied and also place in the grey plastic holders (how ever you call that)). On the two extra rack I plan to install further away there will only be two modules on each, 1746-INT4 and 1746-HSCE. This is to avoid having to have all the wires travelling the distance back to the main panel. Wires for the thermocouple J, 8 of them in all, are a bit expensive. I have started to read the configuration details for setting up the 1746-ASB modules. At this point in time I only have bits and pieces as I went through the document rapidly. I'm overwhelmed though by how to set it up for the dip switches. As we say in French: We will cross the river once at the bridge! or We will cross the bridge once at the river! I have also checked things on encoders and their modules, I will surely will have to start a topic again. Thanks

[Ken Roach 194]

The HSCE and HSCE2 modules are tricky even in the local chassis; read up on them using both the User Manuals and the Knowledgebase.

[Pulsar2003 0]

Thanks Edited 26 Jul 2011 by Pulsar2003

[Pulsar2003 0]

Over the past weeks I had time to read the manuals: 1746-SN; 1746-ASB; 1746-HSCE. I add this information to the project: there are two stations where the oven can be activated and some of it's functions while in cycle or not. I would like to relocate them as they are often in the way and one has had the wires damaged. It seems to be simple to install in the box a 1794-ASB with a 16 input module and 8 output module. Because how the machine is made this is how I would like to make the installation: 1746-A4 (left side)(resistor at this end); 1794-ASB (left side); 1746-SN (middle or main electrical panel); 1794-ASB (right side); 1746-A4 (right side)(resistor at this end). I will exaggerate: this would demand about 500 feet of wire. In AB's literature for both the SN and ASB module the SN is always located first and then it daisy chains to the other modules that can use the RIO. Can this sequence be altered? In the 1746-A4, slot 0 would have the ASB module; in either slot 1 or 3 a 1746-NT4 and 1746-HSCE. In the 1746-HSCE literature I noticed this: "The High-Speed Counter Module, catalog number 1746-HSCE is an SLC 500 family compatible device except with the 1747-ASB Remote I/O Adapter Module. The high-speed module can be used with SLC 5/02 (and above) processors" (page 1-1 of the 1746-UM006B-EN-P). Is-it possible that this has changed over the years as the modules have evolved? Or is it the 1746-HSCE 2? I had planned to use the rack simply to avoid having too many wires to go about from the encoder to the main panel, this also seemed to be the logical solution. For the thermocouples I don't have the choice because this is a part that is constantly in movement and the wires would get damaged (120 volts supply with the Belden). There is still the signal conditioners! The NT4 module uses 8 input words and 8 output words (pade 1-2 of the 1746-UM007C-EN-P). If I understand the literature well for the ASB and SN modules this means that I can choose any of the 2, 1 or 1/2 slot addressing? In this project I'm certainly not going to use the entire potential of the four remote rack. I leave it here and see what the experts thin of it. I don't know if I'm staring at the bark of a tree or at an entire forest! By the way, if I don't use the whole potential of the racks; can there be more than four? Are there other options like the Device net? Thanks Edited 26 Jul 2011 by Pulsar2003

[Ken Roach 194]

:facepalm: I made an incorrect assumption that you caught: The 1747-HSCE module cannot be used in a remote rack with a 1747-ASB. The slightly-more-modern 1747-HSCE2 module can. With regard to the daisy-chaining of RIO devices: the Scanner is depicted at the physical end of the link only by convention. It is perfectly legitimate to have it in the middle or anywhere else along the parallel wire path. The termination resistors are required to be at the physical ends of the links, but the Scanner can be anywhere. You can only transfer 4 words of I/O in Discrete Mode using 1/2 Slot addressing, so that precludes the use of the 1746-NT4 (8 words) with discrete mode. You can use Block Transfers to get that data, so leave the racks at ordinary "1-Slot" mode and conserve your data memory. If I were doing this system I would get an encoder line booster and place the HSCE in the main chassis. Those single-ended signals from the encoder are just asking for trouble if you attempt to run them more than 20 feet or so. The Encoder Products Company "RX/TX Converter" is the gold standard for retransmission of encoder signals. http://www.encoder.com/literature/datasheet-rxtxconverter.pdf

[Pulsar2003 0]