<div class="form-group row">
     <label class="col-sm-3 col-form-label text-right"><b>ANGKA KREDIT BARU</b></label>
            <div class="col-sm-3  ">
                  <?php echo $form->textField($model,'kredit_baru',array('size'=>50,'type'=>'number','maxlength'=>7,
                   'data-validation'=>'number', 'data-validation-allowing'=>'float', 'data-validation-decimal-separator'=>'.',
                   'data-validation-error-msg-number'=>'Harap Diperbaiki','data-validation-optional'=>'true','data-validation- 
                    allowing'=>'range[0.000;999.999],float',
                   'class'=>'form-control')); ?>
           </div>
</div>

Replace coma with dot       
<script>
         jQuery(function($){
           $("input").keypress(function(event) {
             $(this).val($(this).val().replace(',', '.'));
           })
         });  
         </script>