1. SF6 load break fault make switches for overhead networks
SECTOS
SF6 load break fault make switches for overhead networks

2. Distribution network
Sectos NXB + DTU

3. Definition of a Switching Device
A switch CAN A switch CAN NOT
Open a circuit
Close a circuit
Open a Load
Close a Fault
Open a Fault
A disconnector Must provide a safe isolating distance

4. Sectos Sectos switch-disconnector NXB technology NXA technology NXB
12…24 kV (BIL max. 125 kV)
24…36 kV (BIL max. 170 kV)
NXB technology
NXA technology
NXB
NXBD
NXA
Motor up
Manual
Motor up
Motor down
Manual
Conical epoxy bushings
Outdoor epoxy bushings
Conical epoxy bushings

5. Sectos
NXA
36kV, 630A
NXB
kV, 630A
NXBD

6. Sectos NXA 36kV (38kV ANSI) 2-position load break-fault make switch
single or double spring mechanism
Manual or motor operated
Manual operation by hook stick

7. Insulation level (IEC 60265-1 (1998))
Sectos NXA
Insulation level (IEC (1998))
Rated voltage 36 kV
Power frequency withstand voltage, 60 sec wet - to earth and between phases 70 kV - across isolating distance 80 kV
Lighting impulse withstand voltage - to earth and between phases 170 kV - across isolating distance 195 kV

8. Current ratings (IEC 60265-1 (1998))
Sectos NXA
Current ratings (IEC (1998))
Electrical endurance class E2 / E3
Rated normal current 630 A
Mainly active load breaking current 630 A / 400 A
Number of breaking operations CO 50 / 100
Closed loop breaking current 630 A
Line-charging breaking current 40 A
Cable-charging breaking current 40 A
Earth fault breaking current 175 A
Cable charging breaking current under earth fault conditions 87 A
No-load transformer breaking current 20 A

9. Short-circuit ratings (IEC 60265-1 (1998))
Sectos NXA
Short-circuit ratings (IEC (1998))
Electrical endurance class E2 / E3
Short-time withstand current, Ith (3 s) 12,5 kA
Peak withstand current, Idyn, peak 31,5 kA
Short-circuit making current 31,5 / 25 kA
Number of making operations 3 / 5
Mechanical endurance class M2
Number of close-open operations 5000
Ambient air temperature limits oC
Filling pressure 1.5 bar (abs)
Weight with plug-in insulators 95 kg

10. Sectos NXB
12, 17.5 and 24kv
2- or 3-position load break-fault make switch
Single or double spring mechanism
Manual or motor operated
Manual operation by hook stick

11. Insulation level (IEC 60265-1 (1998))
Sectos NXB
Insulation level (IEC (1998))
Rated voltage kV
Power frequency withstand voltage, 60 sec wet
- to earth and between phases kV across isolating distance kV
Lighting impulse withstand voltage - to earth and between phases kV across isolating distance kV

12. Current ratings (IEC 60265-1 (1998))
Sectos NXB
Current ratings (IEC (1998))
Rated normal current A
Mainly active load breaking current (100 CO) 630 A
Line-charging breaking current A
Cable-charging breaking current A
Earth fault breaking current A
Cable charging breaking current under earth fault conditions A
No-load transformer breaking current A

13. Short-circuit ratings (IEC 60265-1 (1998))
Sectos NXB
Short-circuit ratings (IEC (1998))
Short-time withstand current, Ith (3 s) 20 kA
Peak withstand current, Idyn, peak 50 kA
Short-circuit making current 50 kA
Number of making operations n
- main switch 50 kA (CL E2) 3
- main switch 31.5 kA (CL E3) 10
- earthing switch 50 kA (CL E2) 3
- earthing switch 31.5 kA (CL E3) 5

14. Mechanical endurance (IEC 60265-1 (1998))
Sectos NXB
Mechanical endurance (IEC (1998))
Number of close-open operations n
- main switch
- earthing switch
Ambient air temperature limits oC
Filling pressure (abs) bar Weight
- cast resin insulators 81 kg
- silicone insulators 82 kg
- without bushing 71 kg

15. Sectos NXBD 12, 17.5 and 24kV Two switches in same housing
two switched ways and one tapped way
2- or 3-position load break-fault make switches
single or double spring mechanism
Manual operation by hook stick

16. Sectos Rating plate Silicone rubber insulators Earthing terminal
Gas filling valve
Stainless steel
housing (sealed
pressure system,
IEC 56)
Silicone rubber insulators
Series 400 Outer Cone
bushings, M16
Hook-stick lever
Reliable position indicator
Terminal pad

17. Details Large position indicator symbols Reflective colours
The reliable indication of the device fulfills the design and testing of IEC 129 A2

18. Details Mechanical housing made of aluminium alloy
Stainless steel spring mechanism
IPX7

19. Details Manual operation, single spring mechanism
Motor operation, single spring mechanism

20. Details Temperature compensated gas density switch as standard
Optional gas density gauge

21. Details
Optional low gas locking mechanism

22. Details
Stainless steel housing
AISI 304
Laser cut, robot welded

23. Details Outer cone bushings, series 400
Flexible plug-in silicone rubber insulators

24. Details Hook-stick lever (3 position switch)
Hook-stick lever (2 position switch) + optional locking device

25. Accessories
Many different types of mounting accesories

26. Accessories
Different types of terminal pads

27. Current Transformer
Ring type transformer, installed around the bushings
Type: KOKU 072 G4
Ratio: 600/1 A
Burden/Class 3 VA / 5P10
0.5 VA / 5P20
Standards IEC 185

28. DTU (Distribution Terminal Unit)
REC 501
Digital inputs
24 VDC battery
1…2 contactor logic with local control push buttons and MCB’s
Place for communication device
Heating element
IP55 stainless steel enclosure

29. DTU (Distribution Terminal Unit)
REC 523
Digital inputs (15 pcs)
Analog inputs for measuring transformers and sensors (3…9pcs)
24 VDC battery
1…4 contactor logic with local control push buttons and MCB’s
Place for communication device
Heating element
IP55 stainless steel enclosure

30. REC 5xx
REC 501
REC 523

31. Some key signals which are desired from a remotely controlled switch
Desired Signals
Some key signals which are desired from a remotely controlled switch
Position: OPEN / CLOSE / EARTH
Operation: LOCAL / REMOTE
Gas level: Enough gas to permit safe operation
Battery status: enough to operate the switch and maintain communication
Cabinet temperature
Door alarm
Fault passage indicator
Fault passage counter
Measurements: Voltage, Current

32. REC 5xx Communication media Protocols
Network Control protocol
Network
control
system
Remote-controlled
equipment
RMU
Disconnector
DLC
Modem
Radio
REC 5xx
Optionalmodem
Public line
Leased lines
Optional
adapter
Optical cable
RS 232 A
GSM
Adapter
Radio modem
Compact switchgear
Communication media
Protocols
LON / SPA interface ( REC 501 only SPA)
RS232 interface
Fibre-optic connection
Radio modem
Modem (option) for
- conventional radio telephone
- fixed or switched cable connection
- leased or public telephone lines
- GSM
DLC
SPA
LON (for REC 501 with adapter)
ANSI X3.28
RP570 (REC 501)
IEC
DNP 3.0
MODBUS
Others...

33. Feeder Automation Ready Solutions
Ready-made, fully tested packages
Sectos
DTU
REC 523
From remotly controllable packages to automatic sectionalizer functions with current and voltage logic

34. Feeder Automation Ready Solutions
Sectos NXB switch-disconnector
Motor operating device integrated in the switch
CT’s installed around the bushings
Cable for motor control , position indication and gas density monitoring
Control box type DTU131 including REC 523
Optional VT’s for power supply and voltage measurement
Surge arresters recommended as an option

35. Vegetation, nesting birds and other animals?
The sealed enclosure eliminates risks from environmental hazards and increases the reliability of electrical distribution systems.
Solved by Sectos!
Cali, Colombia

36. Salt, sand, moisture and pollution?
The enclosure of stainless steel is hermetically sealed and corrosion resistant. The hydrophobic silicone rubber insulators are well suited even to the most extreme conditions.
Solved by Sectos!
Israel
Norway
China

37. Ice, snow and high altitudes?
The switch inside the sealed tank in an inert SF6 gas atmosphere is insensitive to outside pressure changes. Sectos is also practically maintenance-free.
Solved by Sectos!
Finland
Bolivia (3750 m)

38. Tölby station outside Vaasa, Finland
SECTOS NXBD24. Double switch-disconnectors 2pcs. All 4 motors remote controlled from same DTU131 operating box using REC523 type of RTU.
Before