### Author Topic: Number of I/O and HMI  (Read 1240 times)

#### PLCstar

• Newbie
• Posts: 24
• I'm a ladder logic fool!
##### Number of I/O and HMI
« on: April 22, 2006, 09:05:01 AM »
I have a T100MD888 PLC left over from a job that was cancelled. I have another job here that will require almost 50 relay outputs, just a handful of inputs, and a HMI. So I thought I would add 3 EXP1616R boards.

I just want to make sure that I have figured this out correctly. Am I exceeding some I/O limits if I add that many EXP1616Rs to that PLC along with the HMI? Also will the HMI work (be addressable) plugged into that long daisy chain of I/O?

If I recall when adding I/O to the ...888+ PlC the addressing for the additional I/O is shifted. If I recall the first expansion I/O point is not at #9, but somwhere in the 20's. Is this correct?

I have already started pasting down ladder ideas in your software. I also have added all of the I/O points I think I need in one continuous run, but I realize as I install the extra I/O I might have to shift the points. What I want to know is if I have already referenced that I/O point (name) in a ladder can I still shift that I/O name up or down the I/O point list without causing any trouble?

#### support

• Global Moderator
• Hero Member
• Posts: 3119
##### Re:Number of I/O and HMI
« Reply #1 on: April 24, 2006, 10:07:55 AM »
The default maximum number of I/O a T100MD can support is 96 inputs and 96 outputs. T100MD888+ occupy the first 16 I/Os. Then plus 3 x EXP1616R and MD-HMI, you will have used up a total of 80 inputs and 72 outputs. So you are still within the maximum I/O limit.

For applications that needs more taht 96 inputs and 96 outputs, the latest firmware version allow expansion to 128 inputs and 128 outputs but that require execution of a special SETSYSTEM command which you can email to sales@tri-plc.com to inquire.
Email: support@triplc.com
Tel: 1-877-TRI-PLCS