Dual Algorithm Ltc Condition Monitoring - Advanced Power technologies TTC-1000 Instruction & Operation Manual

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Dual Algorithm LTC Condition Monitoring

The TTC-1000 several set points that the user can employ for LTC conditioning
monitoring. The LTC differential is the mathematical difference between the
probe named LTCDIFF, LTCDIFF1, LTCDIFF2, LTCTANK, SELTANK or
DIVTANK and top oil temperature and therefore is only available in units with
more than one temperature probe. For instance, if P1 is used for Top Oil, P2 for
Ambient, a third probe would need to be available for LTC monitoring of one tap
changer tank. Should the transformer have two tap changer tanks, only one
probe would be available for other functions such as Top Oil.
There are two heating events that can be detected with the TTC-1000:
 Slowly evolving Problems normally associated with coking of the tap
changer contacts.
 Quickly evolving problems associated with a malfunction of the tap
changer mechanism which leads to rapid temperature increases which if
not caught quickly can lead to catastrophic failure of the transformer.
The range of the calculation is from –20 to +20 ºC.
NOTES:
1. When using LTC condition monitoring, it is important to remember to
name one of the probes LTCDIFF, LTCDIF1, LTCDIF2, LTCTANK, SELTANK
or DIVTANK. Evaluation of the LTC set point is not done unless one of the
probes is named for that function (LTCDIFF, LTCDIFF1, LTCDIFF2,
LTCTANK, SELTANK or DIVTANK).
2. LTC differential functions use the first probe named TOP OIL, TOP OIL 1,
TOP OIL 2, or TOP OIL 3.
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