iSFG Switch Disconnector

Switch Disconnector

UN-SFD Switch Disconnector

Gas-insulated indoor switch disconnector

Range from 12 kV to 24 kV and from 630 A to 800 A.

Product Description

Switch Disconnector

Gas-insulated indoor switch disconnector

The UN-SFD is a gas-insulated switch disconnector for medium voltage switchgear within secondary distribution networks. There are several advantages that make the UN-SFD concept suitable for many different applications. For instance the compact size and the lightweight construction of the switch disconnector are significant features for smart integration.

There are two types of operating mechanisms: the single spring device and the double spring device. Motor operation can be added to both types of operating mechanisms.

Feature

Safety

  • Integrated voltage indicator
  • Interlocking device
  • Gas gauge, pressure indicator
  • Inspection windows
  • Non-corrosive leak-proof enclosure
  • Pressure relief channel

Economy

  • Long lifecycle
  • High mechanical endurance
  • Low maintenance costs
  • Low environmental impact

Reliability

  • Each unit is stringently tested
  • Used worldwide in the Uniswitch
  • Extremely durable and reliable operating mechanism

Smart integration

  • Compact size
  • One switch – many applications
  • Easy installation
  • Part of the UNISUN solution
switch disconnector safety

switch disconnector safety

Standards

Compliance with IEC standards: IEC 60694; IEC 60265-1; IEC 60129; IEC 60420; IEC 60282-1; IEC 62271-102; IEC 62271-105; IEC 60265-1, Class E3; IEC 60420

Technical data

Ratings Unit Value Value
Rated voltage kV 12 24
Rated lighting impulse withstand voltage Common value kV 75 125
Across the isolating distance kV 85 145
Rated short duration power frequency withstand voltage Common value kV 28 1) 50
Across the isolating distance kV 32 1) 60
Rated frequency Hz 50/60 50/60
Rated current Ir A 800 630
Rated short time withstand current kA 25 20
Rated duration of short circuit s 2 3
Rated peak withstand current kA 62.5 50
Making and breaking tests (IEC 60265-1, Class E3) for the UN-SFD switch
Mainly active load current A 800 630
Closed-loop distribution circuit current A 800 630
Cable charging current A 50 and 10 50 and 10
Line charging current A 20 20
Cable and line charging current under earth faults A 87 87
Short circuit making current kA 62.5 50
Making and breaking tests (IEC 60420) for the UN-SFD switch – fuse combination
Withstanding and making the cut-off current of the fuse kA 25 20
Breaking test with long prearcing time of fuse ok ok
Breaking capacity at rated transfer current A 1530 920
Mechanical performance
Mechanical endurance of switch close/open Operations 1000 1000
Mechanical endurance of switch open/earth Operations 1000 1000
Ambient temperature
Maximum value oC 40 40
Maximum value of 24 h mean oC 35 35
Minimum value oC -5 3) -5 3)
Altitude above sea level m < 1000 2) < 1000 2)