GE Power Management
745 Transformer Management Relay
5-75
5 SETPOINTS
5.6 S4 ELEMENTS
5
5.6.16 LOSS OF LIFE LIMIT
The Loss of Life Limit element computes the total expended life of the transformer, based on the aging factor
and the actual in-service time of the transformer. For example, if the aging factor is a steady 1.5 over a time
period of 10 hours, the transformer will have aged for an equivalent 1.5
×
10 = 15 hours. The cumulative total
number of hours expended is retained in the relay even when control power is lost. The initial Loss of Life
value, when a relay is first placed in service, can be programmed under the transformer settings. The element
operates on the cumulative total value, with no time delay. The output of this element should be used as an
alarm only, as users may wish to leave the transformer in service beyond the theoretical expended life. The
necessary settings required for this element to perform correctly are entered under:
SETPOINTS/S4 ELEMENTS/INSULATION AGING/LOSS OF LIFE LIMIT
The actual values are only displayed if the Loss of Life option is installed and the ambient
temperature is enabled.
y
LOSS OF LIFE LIMIT
y
[ENTER] for more
This message indicates the start of the
LOSS OF LIFE LIMIT
section. To
continue these setpoints press
or press
for the next section.
LOSS OF LIFE LIMIT
FUNCTION: Disabled
Range: Disabled / Enabled
LOSS OF LIFE LIMIT
TARGET: Self-Reset
Range: Self-reset / Latched / None
Select
None
to inhibit the display of the target message when the element
operates. An element whose “target type” is
None
never disables the LED
self-test feature because it cannot generate a displayable target message.
LOSS OF LIFE LIMIT
PICKUP: 16000 x 10h
Range 0 to 20,000 (steps of 1), providing for a maximum of 200,000 hrs.
Enter the expended life, in hours, required for operation of the element. This
setting should be above the total life of the transformer, in hours. As an
example, for a 15-year transformer, the total number of hours would be
13140
×
10 = 131400.
LOSS OF LIFE LIMIT
BLOCK: Disabled
Range: Disabled / Logc Inpt 1 (2-16) /Virt Inpt 1 (2-16) / Output Rly 1 (2-8) /
SelfTest Rly / Virt Outpt 1 (2-5)
E N T E R
M E SSA G E
NOTE
Summary of Contents for 745 TRANSFORMER MANAGEMENT RELAY
Page 30: ...2 8 745 Transformer Management Relay GE Power Management 2 3 SECURITY 2 GETTING STARTED 2 ...
Page 210: ...7 36 745 Transformer Management Relay GE Power Management 7 2 BLOCK DIAGRAMS 7 SCHEME LOGIC 7 ...
Page 322: ...9 12 745 Transformer Management Relay GE Power Management 9 3 USING 745PC 9 745 PC SOFTWARE 9 ...
Page 396: ...A 4 745 Transformer Management Relay GE Power Management A 1 FIGURES AND TABLES APPENDIXA A ...
Page 400: ...C 2 745 Transformer Management Relay GE Power Management C 1 WARRANTY INFORMATION APPENDIXC C ...
Page 406: ...vi 745 Transformer Management Relay GE Power Management ...
Page 407: ...GE Power Management 745 Transformer Management Relay NOTES ...