Test information should contain all the information during an appliance test, including test metadata, sensor metadata and test data. TestMetaData contains a series of descriptive information in one test. The information is composed of input items and their contents. SensorMetaData element contains two child elements, which are SensorInfoCollection and GroupInfoCollection, respectively. In an XML instance, this branch shall contain the information of sensors that is used in household appliance test. Moreover, the information concerning that how these sensors are grouped should also be included. As illustrated in Figure 16, SensorCollectionOfKeyParameter element contains an unbounded set of SensorOfKeyParameter as its child element which contains a sensorID corresponding to a key parameter. TestDataCollection element contains the test data produced over a period of time. It is a collection that is composed of an unbounded set of TestData elements. Each TestData element contains data related to sensors in the String form and the length of the string is restricted. SensorInfoCollection comprises of a collection of SensorInfo elements. Each SensorInfo element represents a sensor used in one test GroupInfoCollection contains all the group information defined to distinguish sensors well. The detailed description of each group is shown in GroupInfo element.