# AB Compact Logix Boolean Array not showing full array size in UDT **URL:** \ **Category:** Ignition\ **Tags:** vision\ **Created:** [August 8, 2025, 5:30pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544 "2025-08-08T17:30:11Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![andy.hernandez](https://avatars.discourse-cdn.com/v4/letter/a/4491bb/32.png) [@andy.hernandez](https://forum.inductiveautomation.com/u/andy.hernandez)\ **Post date:** [August 8, 2025, 5:30pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/1 "2025-08-08T17:30:11Z")
Software: Ignition Version 8.1 Module: Vision Project: CompactLogix PLC Arrays inside an Ignition UDT I have the arrays shown below inside an Ignition UDT definition that looks something like this: 1. A1\_Rack.Part\_ID\_Array[224] type STRING 2. A1\_Rack.PickTime\_Array[224] type DINT 3. A1\_Rack.PlaceTime\_Array[224] type DINT 4. A1\_Rack.Pockets\_Disabled\_Array[224] type BOOL 5. A1\_Rack.Pockets\_Array[224] type BOOL Can you please explain the issues I'm having when I instantiate these five arrays? When I browse to the tags Items 1,2,3 shows all 224 elements while 4 and 5 (of type Booleans) only shows 6 elements ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/b/1/b1d81c8b960913d599252ff4840a9d010f0df496.png) ---
**Author:** ![ryan.white](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ryan.white/32/73193_2.png) [@ryan.white](https://forum.inductiveautomation.com/u/ryan.white)\ **Post date:** [August 8, 2025, 5:39pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/2 "2025-08-08T17:39:28Z")
Bool arrays in CLX are actually DINTS behind the scenes. 7 DINTS x 32bits = 224 bits. ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [August 8, 2025, 5:39pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/3 "2025-08-08T17:39:50Z")
Logix BOOL arrays are actually packed into DWORD arrays with nothing visible to external connections to indicate they’re actually a BOOL array. > [@Problem on Allen-Bradley Logix Driver array of bit](https://forum.inductiveautomation.com/t/problem-on-allen-bradley-logix-driver-array-of-bit/73587/2): > > Logix boolean arrays are really DWORD arrays, where each dword supplies 32 of the booleans. Drill in deeper. Your original boolean address of somebooltag[B] translates to an OPC Item Path of somebooltag[J].K where J=B/32 and K=B%32. And no, this is not a bug. The logix processor really does tell a connected system that these are DWORDs. The only booleans that are actually reported as true booleans are stand-alone boolean tags (non-array). Even booleans within UDTs aren't "real" booleans, a… ---
**Author:** ![andy.hernandez](https://avatars.discourse-cdn.com/v4/letter/a/4491bb/32.png) [@andy.hernandez](https://forum.inductiveautomation.com/u/andy.hernandez)\ **Post date:** [August 8, 2025, 5:41pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/4 "2025-08-08T17:41:59Z")
How do I access Individual elements? ---
**Author:** ![ryan.white](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ryan.white/32/73193_2.png) [@ryan.white](https://forum.inductiveautomation.com/u/ryan.white)\ **Post date:** [August 8, 2025, 5:43pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/5 "2025-08-08T17:43:21Z")
You can access bits by adding `.#` to the tag path where `#` is the index of the bit in that DWORD, so anything from 0-31. For example, item `A1_Rack.Pockets_Array[122]` in CLX would be `ns=1;s=[PLC]Program:Mazak_Racks.A1_Rack.Pockets_Array[3].26` ---
**Author:** ![robertm](https://avatars.discourse-cdn.com/v4/letter/r/ea5d25/32.png) [@robertm](https://forum.inductiveautomation.com/u/robertm)\ **Post date:** [August 8, 2025, 5:58pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/6 "2025-08-08T17:58:27Z")
You can also create an Ignition UDT to individualize the bits into individual tags…that's what I do with 32 bit DiNTs for alarm bits. Just create a UDT type with a string root parameter, then individual bits that are {root}.0 to {root}.31. Makes it easier to define alarms, bindings, etc ---
**Author:** ![andy.hernandez](https://avatars.discourse-cdn.com/v4/letter/a/4491bb/32.png) [@andy.hernandez](https://forum.inductiveautomation.com/u/andy.hernandez)\ **Post date:** [August 8, 2025, 6:01pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/7 "2025-08-08T18:01:53Z")
That sounds very interesting Robert. Are you able to show a screenshot showing the steps involved? ---
**Author:** ![robertm](https://avatars.discourse-cdn.com/v4/letter/r/ea5d25/32.png) [@robertm](https://forum.inductiveautomation.com/u/robertm)\ **Post date:** [August 8, 2025, 6:05pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/8 "2025-08-08T18:05:29Z")
Unfortunately, traveling at the moment. There should be some examples if you search the forums. Otherwise, I can probably get you something tomorrow. ---
**Author:** ![robertm](https://avatars.discourse-cdn.com/v4/letter/r/ea5d25/32.png) [@robertm](https://forum.inductiveautomation.com/u/robertm)\ **Post date:** [August 9, 2025, 3:44pm UTC](https://forum.inductiveautomation.com/t/ab-compact-logix-boolean-array-not-showing-full-array-size-in-udt/109544/9 "2025-08-09T15:44:26Z")
[tags.json](https://forum.inductiveautomation.com/uploads/short-url/kDCHR2TUbTec1tI5Us5GQeGzvBB.json) (2.2 KB) [UDT tags.json](https://forum.inductiveautomation.com/uploads/short-url/sbkGN8VYQkEk5xLy67rC35EhgBq.json) (9.5 KB) Attached is an UDT example and a tag example using that UDT. For your case, if you want specific array.y tags, expand the UDT to add an INDEX parameter, and change the elements to include the [INDEX] to your CLX tag.