Вы можете использовать атрибут k-value и установить значение по умолчанию
DEMO
angular.module("KendoDemos", [ "kendo.directives" ])
.controller("MyCtrl", function($scope){
$scope.getType = function(x) {
return typeof x;
};
$scope.isDate = function(x) {
return x instanceof Date;
};
$scope.value = '08:00 AM';
})
<!DOCTYPE html>
<html>
<head>
<base href="http://demos.telerik.com/kendo-ui/datetimepicker/angular">
<style>html { font-size: 14px; font-family: Arial, Helvetica, sans-serif; }</style>
<title></title>
<link rel="stylesheet" href="//kendo.cdn.telerik.com/2016.3.1118/styles/kendo.common.min.css" />
<link rel="stylesheet" href="//kendo.cdn.telerik.com/2016.3.1118/styles/kendo.default.min.css" />
<link rel="stylesheet" href="//kendo.cdn.telerik.com/2016.3.1118/styles/kendo.default.mobile.min.css" />
<script src="//kendo.cdn.telerik.com/2016.3.1118/js/jquery.min.js"></script>
<script src="//kendo.cdn.telerik.com/2016.3.1118/js/angular.min.js"></script>
<script src="//kendo.cdn.telerik.com/2016.3.1118/js/kendo.all.min.js"></script>
</head>
<body>
<div id="example" ng-app="KendoDemos">
<div class="demo-section k-content" ng-controller="MyCtrl">
<h4>Select time:</h4>
<input kendo-time-picker="dtp"
k-value="'08:00 AM'"
ng-model="value"
style="width: 100%;" />
{{value}}
</div>
</div>