Corrosion Protection; Operating Conditions - Siemens GEAFOL Operating Instructions Manual

GEAFOL- / CARECO-Cast-resin Transformer/ Operating Instructions
Scope
These operating instructions apply to cast-resin
transformers in three-phase or single-phase design
including all special transformers such as converter and
starpoint transformers of the series
GEAFOL / GEAFOL Neo; Typ 4G...
CARECO / CARECO Neo; Typ 4G...
Rating plate
On the transformer and the housing (if any) is a rating
plate with the nominal values and define operating condi-
tions.
Usage
Unless otherwise agreed, the transformers are designed in
accordance with the applicable standards for the following
cooling air values:
• 40° Celsius at any given time
• 30° Celsius monthly average of the hottest month
• 20° Celsius yearly average
GEAFOL-/CARECO-transformers intended for installation at
altitudes over 1,000 m above sea level are identified as
such on the rating plate, which cites the maximum permis-
sible installation elevation.
Classification in accordance
3.1
to IEC 60076-11
GEAFOL-/CARECO transformers fulfil the classes defined in
EC 60076-11:
Environmental class
GEAFOL/CARECO: Standard E2 - Frequent condensation or
light pollution or combination of both
GEAFOL NEO /CARECO NEO: Standard E3 -
Frequent condensation or heavy soiling, even both at the
same time. (E3 for wind turbines on request.)
Fire behaviour class F1
The characteristics of the transformer limit the risk of fire.
Climatic class
The following climate classes are available for
GEAFOL/CARECO transformers:
Climatic class
and
C2*
C3**
C4
*) Standard for CARECO-transformers
**) Standard for GEAFOL-transformers
For lower ambient temperatures, external preheating
equipment must be installed on site.

Corrosion protection

Corrosion protection is available according to the custom-
er's specification in
C2H (e.g. interior, rural areas), C4H (e.g. industrial atmos-
phere. coastal) or C5H (e.g. aggressive atmosphere, off-
shore) executed. CX (extreme) in agreement with cus-
tomer.
Frequency of energization
The frequency of energization on is limited to max. 3 times
a day, max. 50 times a year, unless otherwise agreed.
Load dump conditions for machine transformers
Max. Voltage rise at load dump 140% of Unenn for max. 5
seconds.

Operating conditions

The requirements at the installation site according to IEC
60076-11, chap. 4.2 must be observed, in particular with
regard to grounding of transformers
 Protection of the transformer against overvoltages

Load current harmonic content

Symmetry of three-phase supply voltages

Environmental conditions concerning biological envi-
ronmental conditions, chemically active substances,
mechanically active substances, mechanical conditions
Regenerative mode
CAUTION!
The transformer may only be used in regenerative mode
(Step-up) with an appropriate protective device.
Temperature for
Transport and
Operation
storage
to -25°C to -25°C
to -40°C to -25°C
to -50°C to -40°C
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