SR489-P1-LO-A20-E Generator management relay in series 489
There are several classes of setpoints, each distinguished by the way their values aredisplayed and edited.
The relay’s menu is arranged in a tree structure. Each setting in the menu is referred to as asetpoint, and each setpoint in the menu may be accessed as described in the previoussection.
The settings are arranged in pages with each poge containing related settings; forexample, all the Phase Overcurrent settings are contained within the same page. Aspreviously explained, the top menu page of each setting group describes the settingscontained within that page. Pressing the MEssAGE keys allows the user to move betweenthese top menus.
All of the 489 settings fall into one of following categories: device settings, system settings.digital input settings, output relay settings, current element settings, voltage elementsettings, power element settings, RTD temperature settings, thermal model settings.monitoring settings, analog input/output settings, and testing settings.
IMPORTANT NOTE: Settings are stored and used by the relay immediately after they areentered. As such, caution must be exercised when entering settings while the relay is inservice. Modifying or storing protection settings is not recommended when the relay isin service since any incompatibility or lack of coordination with other previously savedsettings may cause unwanted operations.
Now that we have become more familiar with maneuvering through messages, we canlearn how to edit the values used by all setpoint classes.
Hardware and passcode security features are designed to provide protection againstunauthorized setpoint changes. Since we will be programming new setpoints using thefront panel keys, a hardware jumper must be installed across the setpoint access terminalsiC1 and C2 on the back of the relay case. Attempts to enter a new setpoint without thiselectrical connection will result in an error message.
The jumper does not restrict setpoint access via serial communications. The relay has aprogrammable passcode setpoint, which may be used to disallow setpoint changes fromboth the front panel and the serial communications ports. This passcode consists of up toeight (8l alphanumeric characters.
The factory default passcode is “0”. when this specific value is programmed into the relay ithas the effect of removing all setpoint modification restrictions. Therefore, only thesetpoint access jumper can be used to restrict setpoint access via the front panel andthere are no restrictions via the communications ports.
When the passcode is programmed to any other value, setpoint access is restricted for thefront panel and all communications ports. Access is not permitted until the passcode isentered via the keypad or is programmed into a specific register lvia communications).Note that enabling setpoint access on one interface does not automatically enable accessfor any of the other interfaces li.e., the passcode must be explicitly set in the relay via theinterface from which access is desiredl.