HT Panels are manufactured by many companies. Sometimes there is an existing panel of a particular make and a new panel of another make has to be installed, an Adapter Panel is used to couple the two different types. This is so because the placement of busbars is different for different panel designs. Thus Adapter Panels are used to couple the two different types. Control and Relay panels are used when a particular panel has to be operated from a different position like a separate common room, either for convenience or due to extreme weather conditions. They are thus coupled to the panels for communication facilities. These will help to monitor the changes in ratings like current/voltage etc and breaker operation from another position.