Advice or help accessing object items.

Once you get the posted value, how do you save it if you don't know the name of the dropdown element in your form?
The selected value in a dropdown belongs to the name of the <select> ... </select> stucture.
This part needs some more explanation, please also share the code of your view.

Besides that, your function translateDropDown can be a lot shorter:

PHP Code:

public function translateDropDown($type, $id){  

        $table = 'fx_categorycomponents' . $type;
        $this->db->select($type);
        $this->db->from($table);
        $this->db->where('id', $id);
        $this->db->order_by($type, 'asc');
        $query=$this->db->get();
        return $query;    
        
    }//end translateDropDown