GE L30 Instruction Manual page 424

CONTROL ELEMENTS CHAPTER 5: SETTINGS
Figure 5-128: Acknowledge mode
5
Application example
Consider an application where the selector switch is used to control setting groups 1 through 4 in the relay. The setting
groups are to be controlled from both user-programmable pushbutton 1 and from an external device via contact inputs 1
through 3. The active setting group is to be available as an encoded three-bit word to the external device and SCADA via
output contacts 1 through 3. The pre-selected setting group is to be applied automatically after five seconds of inactivity
of the control inputs. When the relay powers up, it is to synchronize the setting group to the three-bit control input.
5-246 L30 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL