5–92 745 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
S4 ELEMENTS CHAPTER 5: SETPOINTS
FIGURE 5–40: Hottest-spot limit scheme logic
5.6.13.3 Aging factor limit
PATH: SETPOINTS S4 ELEMENTS INSULATION AGING AGING FACTOR LIMIT
The aging factor limit element provides a means of detecting when a transformer is aging
faster than would normally be acceptable. The element operates on the computed aging
factor, which in turn is derived from the computed hottest-spot value. The aging factor
value will revert to zero if the power supply to the relay is interrupted. The necessary
settings required for this element to perform correctly are entered under:
• AGING FACTOR LIMIT PICKUP: Enter the aging factor required for operation of the
element. This setting should be above the maximum permissible aging factor under
emergency loading condition and maximum ambient temperature.
AGING FACTOR []
LIMIT
AGING FACTOR LIMIT
FUNCTION: Disabled
Range: Enabled, Disabled
MESSAGE
AGING FACTOR LIMIT
RLYS (1-8): --------
Range: 1 to 8
MESSAGE
AGING FACTOR LIMIT
TARGET: Self-Reset
Range: Self-Reset, Latched, None
MESSAGE
AGING FACTOR LIMIT
PICKUP: 2.0
Range: 1.1 to 10.0 in steps of 0.1
MESSAGE
AGING FACTOR LIMIT
DE L AY: 1 0 min
Range: 0 to 60000 min. in steps of 1
MESSAGE
AGING FACTOR LIMIT
BLOCK: Disabled
Range: Logc Inpt 1 to 16, Virt Inpt 1 to
16, Output Rly 2 to 8, SelfTest
Rly, Vir Outpt 1 to 5, Disabled
To Next Page
Loading...
