General Warnings - c.a.p.t. AT Serie Manual Del Instrucciones

GENERAL WARNINGS

MAIN CHARATERISTIC
this is an off-circuit tap changers. It means all switching manoeuvre must be performed after disconnecting
transformer by the electrical net opening the sectionalising switches, both HV and LV side, so transformer
becomes off-circuit.
DIMENSION
All dimension reported in case of drawings attached are in millimetres (mm)
TRANSFORMER OIL
All our tap changers are suitable to work in oil immersed transformers according to standard IEC 60296.
In case user need to use specific oil (silicon, synthetic or vegetal) it is necessary consulted CAPT technical
office who verify the functionality of tap in all the mechanicals, electrical and chemical characteristics.
INSULATION MATERIAL
The insulating materials used are bakelite (paper laminates and phenoplastic resin) of "E" thermal class.
GASKET
Gasket supply in our tap changers and in our transmission drive handles are type NBR and they are suitable
for oil transformer, indicate for temperature in oil between -25°C and +100°C and for temperature on air
between -25°C and +40°C, according to IEC 60214-1/2.
On request, we can supply tap changer with special rubber for low temperature till -60°C and for high
temperature till +200°. These gaskets are suitable for oil transformer and they can be in HNBR, VITON, in
Silicon rubber. They can be used in arctic or tropical conditions.
DRYING TREATMENT
Different drying treatment can be process by customer: oven, in a vacuum autoclave, vapour-phase or
other. In this process is normally included tap changer too. The maximum temperature suggested by CAPT
for our tap changers is 100°C-120°C for a time or 24÷36h.
DRYING TREATMENT IN CASE OF BEVEL GEAR AND DRIVE HANDLE
It is better to leave out from drying treatment the drive handle and bevel gear.
In case it is impossible to leave them out, we suggest to strictly respect the temperature recommended
when you need drive handle with micro switch for electrical lock or electrical position transmitter.
WHEN CONTACT CAPT
In the following cases please contact CAPT:
• For temperature condition higher/lower then suggest
• For temperature condition higher/lower then suggest
• For hard temperature conditions, with possibility of snow or sand storming, or in potential seismic area.
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