how many I/O module can be placed in local bank for 1769-33ER?

[pittlei]

Hi, I am trying to understand in theory how many I/O module I can place in the local bank for the compactlogix 1769-L33ER .

the bulletin says max Local Expansion Modules Supported is 16.

the power supply must be within 4 slots of controller.
the maximum distance between the I/O module and power supply is 8.


can i place the modules like way below?

controller|IO1-3|Power supply|IO4-11|end cap

in this way, I can place 11 I/O modules in the local bank?

thanks

 

[Bullzi]

Yes that is how I have done it in the past. After that you will have to add another power supply and then IO12-16.

 

[ASF]

The limitation is in the modules themselves, each of which have a power supply distance limit. The CPU has a distance rating of 4 (i.e. 3 I/O modules between controller and power supply), which is why you can only have 3 modules to the left of your P/S. To the right, you can have as many modules as the controller can support, as long as you don't exceed any of those module's distance ratings.

Most modules have a distance rating of 8, so as you suggested, you can *usually* put 8 modules to the right of your power supply. A notable exception is the 1769-OB32 which has a distance rating of 6. Some specialty modules also have lower ratings.


Once you exceed the distance rating, you have to use a bus extension module, and make a second bus with its own power supply. As you don't have a CPU on the second bus, you can theoretically add 8 modules either side of the P/S on that bus, for a total of 16 additional modules - again, as long as you don't exceed any one module's distance rating, and as long as you keep within the total module limit of your controller.

 

[Helliana]

Also, you have to make sure you do not overload your power supply. There are two different capacity supplies and cards power consumption varies.


The easiest way to make sure everything will work is use Rockwell's free Integrated Architecture Builder software and configured the cards in it. It will tell you if a card has a different distance rating or if you overload your power supply. It will also give you the part numbers for the expansion endcaps if you need.

 

[JaxGTO]

Building a CompactLogix is a nice feature of the Integrated Architecture Builder (IAB) program. It will help with power supplies as well. You can get it from your distributor.

 

[Robobob]

You can Download IAB here. It is part of the Product Selection Toolbox.
https://www.rockwellautomation.com/...docid=01503dfdb8a20bf09c86944a6f44364bhttp://