ABB RELION REX640 Technical Manual page 1390

Condition monitoring functions
methods of calculation. If
is calculated as shown in
V
IEC
If the setting
shown in
V
IEEE
Where
V
IEC
V
IEEE
θ
h
The calculated value of the relative ageing rate, AGEING_RATE is given as an output
in the Monitored data view.
The module also calculates the average ageing rate, AVG_AGE_RATE, over a specified
time period given by the
period can be set to "DAY", "WEEK", "MONTH" or "YEAR".
For example, if the
AVG_AGE_RATE is updated every day with the average ageing rate since the day
the calculation started. Once a month is completed, the AVG_AGE_RATE is calculated
over the previous 30 days. That is, after the 31st day, the average ageing rate is
calculated from day 2 to day 31 and so on.
If the
AVG_AGE_RATE is refreshed every day at 12:00 hours, but if it is set to "YEAR", the
AVG_AGE_RATE is refreshed once in 30 days.
The calculated AVG_AGE_RATE is given as an output in the Monitored data view.
Loss of life calculation
The momentary loss of life can be calculated as the product of the momentary
ageing rate and the time step over which the momentary ageing is calculated.
DL
n
1390
Equation 334
( )
θ − 98
h
2 6
=
Ageing rate method is set to "IEEE", the ageing rate is calculated as
Equation 335
.
15000 15000
−
110 273 θ 273
+ +
e
h
=
Momentary ageing rate as per IEC method
Momentary ageing rate as per IEEE method
The calculated hot-spot temperature
Insul paper type is set to "Upgraded", the IEEE method is
If the setting
used for calculating the ageing rate irrespective of the value of
rate method setting.
Avg Age rate period setting. The setting Avg Age rate
Avg Age rate period is set to "MONTH", the output
Avg Age rate period is set to "DAY", "WEEK" or "MONTH", the calculated
The function considers month as 30 days and correspondingly a year as
12 months or 360 days.
V Dt
= ⋅
n
Ageing rate method is set to "IEC", the relative ageing rate
.
1MRS759142 F
(Equation 334)
(Equation 335)
Ageing
(Equation 336)
REX640
Technical Manual