Point I/O Basics

Get the 1734-SG001 Selection Guide for the POINT I/O family. It addresses a lot of the higher-level questions about how POINT I/O is selected and installed.

Your friendly neighborhood A-B distributor may be able to help you get introduced to these technologies too.

But I'll take a shot at some of your questions.

1. Yes, you'll need a repeater or switch if your Ethernet cable is more than 100 meters long. Fiber optics is really great for long distances, too.

2. Managed switches are great for telling you when you're getting bad signal on the device, and they're great for constraining multicast traffic. Multicast isn't required in a single-controller network so the need for managed switches is less than it used to be. I still like to get them when I can, because nothing's more frustrating than troubleshooting a network that has no diagnostic features.

3. RA simplified the "CIP connections and TCP connections" when they rolled out the new CompactLogix 5370 family. Instead they just say "node", and provide enough CIP capacity to handle anything you can connect.

4. A 1734-AENT is a Node, and a C-More is a Node, and your laptop PC is a Node.

5. The "Chassis Size" set in the 1734-AENT and the Chassis Size value in RSLogix 5000 have to match. If you create a 10-slot "Chassis" but have 2 modules installed the connection won't run.

Oh, and when you're setting up, use the 1734-AENT/B. It's not easy to switch between Series letters once it's already configured, and all new stock has been Series B for a couple of years.

6. For the 1734-IE2C, Analog data is in 16-bit Words, so you won't be addressing the individual bits.

For the 1734-IE2C module, the two analog channels will have their input data in RCOM:1:I.Ch0Data and RCOM:1:I.Ch1Data.

The CompactLogix uses a SINT as the data container for all the 2 and 4 and 8 bit discrete modules. The unused bits are just unused.

Narlin said:

[FONT=&quot]1. [/FONT][FONT=&quot]My remote location is 200’ from the 1769-L30ER PLC, before any up/down wire routes. If it happens that the cable exceeds 300’, will a powered unmanaged switch placed halfway along the route amplify the signal adequately?[/FONT]​

Click to expand...

I would never use a switch to extend distance. You now have to get power to a third location between your cabinets and now your switch is not located with any other equipment. If you need to go more than 100m use fiber media. It's the right thing to do.

Narlin said:

[FONT=&quot]2. [/FONT][FONT=&quot]If the PLC is connected to an internet accessible router (if, if, if), is it needed to use a managed switch? If so, what does that do that is so wonderful?[/FONT]​

Click to expand...

I wouldn't bother with an unmanaged switches, ever. The big three reasons: no security, no network segmentation, no diagnostics.

My RSLogix 5000 is V20.03.00(CPR 9 SR 5). When i add the 1734-AENT, only series A is available inthe drop down. how do you get B?

I'm surprised V20 doesn't include the 1734-AENT/B module in the I/O list.

But no matter; you need to download and install the 1734-AENT/B "Add On Profile".

Start here:

http://www.rockwellautomation.com/rockwellautomation/support/downloads.page

Cool. thanks for the advice.

Ken Roach said:

3. RA simplified the "CIP connections and TCP connections" when they rolled out the new CompactLogix 5370 family. Instead they just say "node", and provide enough CIP capacity to handle anything you can connect.

4. A 1734-AENT is a Node, and a C-More is a Node, and your laptop PC is a Node.

Click to expand...

I agree with most that you have put down except the evaluation of Nodes.

1734-AENT is a Node

C-More Might be a Node (Only if it is in the I/O configuration section. I know I never put Panelviews there so they would NOT be considered a Node)

Laptop is NOT a Node

Check out 474754 on the knowledgebase

I have attached it for those without access

The Cmore OIT does not have to be listed in the tree. It works very similarly to a PanelView (but in my opinion - easier). I never really thought my laptop was node. It would be interesting to load up the L30ER or a lesser model and see if when all nodes were full you could still connect with the laptop.

There is 1 glaring error in the original post. I mistakenly named an analog module IE2C, whenever I intended to have put in a digital module. When the correct digital module was put into the tree, everything made sense.

Narlin said:

The Cmore OIT does not have to be listed in the tree. It works very similarly to a PanelView (but in my opinion - easier). I never really thought my laptop was node. It would be interesting to load up the L30ER or a lesser model and see if when all nodes were full you could still connect with the laptop.

Click to expand...

I have already tested the "Node" theory. You will get an error (once you compile) if you add too many nodes.