a-eberle REG-DA - Operating Hours (2) Details; Loss of Life Calculation

Page 11
Basic description of the Transformer Monitor
LEREF "Verzeichnis Ueberschrift" \* MERGEFORMAT Index
Fehler! Verwenden Sie die Registerkarte 'Start', um Verzeichnis Ueberschrift
dem Text zuzuweisen, der hier angezeigt werden soll.Inhaltsverz
Block diagram of the hot-spot calculation and the cooling stage control
Figure 3: Block diagram
K
:
Load factor = I / IN
Θ
h
:
Hot-spot temperature
Θ
0
:
Oil temperature (measured)
Θ
hp
:
Expected hot-spot temperature
H
gr
:
Hot-spot to top-oil gradient
Y
:
Winding exponent
∆Θ
h
:
Hot-spot temperature increase
Figure 4: Oil temperature measurement diagram
If a temperature transducer has already been allocated to measure the oil temperature, the
oil temperature can be fed into the controller as mA input. If necessary, the PT100 temper-
ature sensors can also be connected directly in a three-wire circuit.