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There are several classes of setpoints, each distinguished by the way their values are displayed and edited. The relay's menu is arranged in a tree structure. Each setting in the menu is referred to as a setpoint, and each setpoint in the menu may be accessed as described in the previous section. The settings are arranged in pages with each page containing related settings; for example, all the Phase Time Overcurrent 1 settings are contained within the same page. As previously explained, the top menu page of each setting group describes the settings contained within that page. Pressing the MESSAGE keys allows the user to move between these top menus. A complete editable setpoint chart is available as an Excel spreadsheet from the GE Multilin website at http://www.GEmultilin.com. All of the 750/760 settings fall into one of following categories: device settings, system settings, logic input settings, output relay settings, monitoring settings, control settings, and testing settings. Note IMPORTANT NOTE: Settings are stored and used by the relay immediately after they are entered. As such, caution must be exercised when entering settings while the relay is in service. Modifying or storing protection settings is not recommended when the relay is in service, since any incompatibility or lack of coordination with other previously saved settings may cause unwanted operations. Now that we have become more familiar with maneuvering through messages, we can learn how to edit the values used by all setpoint classes. Hardware and passcode security features are designed to provide protection against unauthorized setpoint changes. Since we will be programming new setpoints using the front panel keys, a hardware jumper must be installed across the setpoint access terminals (C10 and C11) on the back of the relay case. Attempts to enter a new setpoint without this electrical connection will result in an error message. The jumper does not restrict setpoint access via serial communications. The relay has a programmable passcode setpoint, which may be used to disallow setpoint changes from both the front panel and the serial communications ports. This passcode consists of up to eight (8) alphanumeric characters. The factory default passcode is “0”. When this specific value is programmed into the relay it has the effect of removing all setpoint modification restrictions. Therefore, only the setpoint access jumper can be used to restrict setpoint access via the front panel and there are no restrictions via the communications ports. When the passcode is programmed to any other value, setpoint access is restricted for the front panel and all communications ports. Access is not permitted until the passcode is entered via the keypad or is programmed into a specific register (via communications). Note that enabling setpoint access on one interface does not automatically enable access for any of the other interfaces (i.e., the passcode must be explicitly set in the relay via the interface from which access is desired).