In pega 7.4 version , 

I have set a max length of a field in a section . The properties for this field are as below :

Number instead of Text Input

Presentation tab: Auto 

                            Property Value

                            Max length

                            Editable Format : Number

                            Read only Format  Number

The max length of the field is getting set properly.

There is a drop down in the same layout . In this dopdown Actions tab , Postvalue and refresh section .

When changing the value in the drop down , max length of the above field is not working.

Please let me know how to resolve this issue.