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Electrical characteristics of medium voltage
capacitors (continued)
PROTECTION DEVICES FOR "ALL-FILM" MV CAPACITORS (continued)
MEDIUM VOLTAGE RANGE
There are four protection options for "all-film"
MV capacitors:
Without internal fuses and external protection by
unbalance monitoring
With internal fuses and external protection by
unbalance monitoring
Without pressure monitoring device and external
protection by HRC fuses
With pressure monitoring device and external
protection by HRC fuses
Capacitor power and voltage
Capacitor
connection
Capacitor protection
The choice between these four options is dependent on
the following criteria:
Electrical characteristics of the capacitor (power,
voltage, connection)
Customer's requirements concerning the sensitivity
of the protection device
The following table gives the possible type of protection for the capacitor and its advantages, according to the
above criteria.
Associated external
protection
Advantages
All powers and all voltages Single phase Without internal fuse Unbalance
P ≥ 200 kVAr and U ≤ 13 kV Single phase With internal fuses Unbalance
All powers and U ≤ 12 kV
Three-phase
Without pressure
monitoring device
HRC fuses
All powers and U ≤ 12 kV
Three-phase
With pressure monitoring
device
HRC fuses
INSTALLATION CONDITIONS FOR "ALL-FILM" MV CAPACITORS
Temperature class
Standard: - 25/+ 45°C:
- 45°C average over 1 hour
- 40°C average over 24 hours
- 30°C average over 1 year
Protection against corrosion
Installation possible: indoor or outdoor
Stainless steel case, with one coat of primer and
several top coats (RAL 7033)
Compatibility with the environment
"All-film" capacitors are impregnated with a
(PCB-free) biodegradable liquid dielectric. Their
installation does not require any particular precautions
with regard to the environment.
Other temperature classes on request,
please consult us
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