Start Supervision - GE 869 Instruction Manual

CHAPTER 4: SETPOINTS

Start Supervision

NOTE:
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
Start Supervision consists of four elements that guard against excessive starting duty. All
Start Supervision elements operate the FlexLogic operand Output Relay 3 ("Start Inhibit"). In
addition to Start Supervision elements, the Start Inhibit operand relay also operates when
the Phase Reversal element or Any Trip operates, as shown in the following figure: Start
Inhibit FlexLogic operand. If the condition that has caused the trip is still present (e.g. hot
RTD), the Start Inhibit operand relay will not reset until the condition is no longer present or
the lockout time has expired. Auxiliary Output Relay, energized by the Start Inhibit
operand, changes state only when the motor is stopped to accommodate control circuits
that must be continuously energized, such as a contactor.
The Start Inhibit operand is programmed as factory default to energize the auxiliary
Output Relay 3, therefore, it is recommended to use the auxiliary Output Relay 3 to inhibit
the closing of the motor switching device, as illustrated by the figure: Typical Wiring
Diagram in chapter 2.
Figure 4-142: Start Inhibit FlexLogic operand
The four elements of Start Supervision are: Thermal Start Inhibit, Maximum Starting Rate,
Time Between Starts, and Restart Delay.
CONTROL
4–335