Select Power Manager under the Programs option in the Workspace menu.
If you are using CDE, you also can start up dtpower the following way:
Click the Power Manager icon in the Application manager - System-Admin folder.
For more information on the Workspace menu, refer to the Solaris Common Desktop Environment: User's Guide or the Solaris User's Guide.
Remember that you cannot modify settings in the Power Manager window unless you were superuser for the system when you started dtpower.