Recloser THO-RC27 for the Smart Grid network

THO-RC27 automatic overhead circuit breaker Recloser consists of the switching unit of the THO-RC27 recloser and control unit SRC. Each switching unit pole has its own vacuum interrupter. All poles are mechanically coupled with a synchronizing shaft which guarantees simultaneous three-phase operation. Vacuum interrupters are opened and closed using a simple electromagnetic actuator with an effective operating lifespan of thirty thousand operations. The electromagnetic drive is actuated by the energy stored in the capacitors. It is composed of one movable part, which differentiates this electromagnetic drive from ordinary spring charged mechanisms. Vacuum interrupters and an electromagnetic drive are placed in completely sealed casing with an IP 65 protection degree.

The switching unit can be opened manually using a mechanical rod, actuating manual trip and lock out handle. After being opened manually, the circuit breaker is mechanically and electrically locked out. The circuit breaker position is mechanically indicated with a visual indicator placed at the bottom of the cubicle and electrically with the SRC control unit, which controls the position of the circuit breakers auxiliary contacts. External cover of the bushing insulators is made from water-repellent silicone rubber. Voltage measurement is performed by capacitive voltage dividers installed inside all bushing insulators. Current measurement is performed by installation of the external current transformers 1A secondary current or Rogowski coils on the bushing insulators.

The SRC control unit is designed for complex operation of Recloser THO-RC, incorporating digital protection with a function of SO-54SR- 1xx- REK bay controller and a communication module of any manufacturer, for example: Mikronika MSG- 6xx, Elkomtech EX- BRG, etc., which integrates the following functions: metering, protecting, controlling with a switching unit, telemechanics, automation and multi-channel fault recorder, as well as storing and processing information concerning network parameters and occurring events.

A detailed description of protection and communication modules is included in separate documentation depending on the type of the module used. ZUPE S.A. makes this documentation accessible after an enquiry is made.


  • possibility to install current transformers or Rogowski coils (depending on customer’s requirements), and very fast transformer or coil replacement, without the need to change the entire switching unit,
  • voltage meter from both sides using capacitive voltage dividers,
  • easy and very fast electromagnetic drive,
  • dry air solid isolation
  • possibility of manual opening and locking of the recloser without external power supply.

Recloser THO-RC27 parameters

Compliance with standards:

  • IEC 62271-111 - High Voltage Switchgear and Controlgear — Part 111: Automatic circuit  reclosers and fault interrupters for alternating current systems up to 38 kV.
  • PN-EN 62271-1 - “High Voltage Switchgear and Control gear – Part 1: Common specifications”,
  • PN-EN 62271-100 - “High Voltage Switchgear and Control gear – Part 100: Alternating current circuit breakers”
  • PN-EN 61140:2005/A1 - Protection against electric shock. Common aspects for installation and equipment
Recloser THO-RC27 parameters
Rated voltage Ur 27kV
Rated frequency – number of phases fr 50-60 Hz-3
Power insulation level withstand test frequency (underground/ interphase)
     - dry test (1 minute) 60/70 kV
     - wet test (10 s)

50/ 60kV
Rated lighting impulse withstand voltage 1,2 /50ms (underground/ interphase) 125/150kV
Rated continuous current Ir 630A
Rated short-time withstand current Ik 12,5kA
Rated peak current strength Ip 32,5kA
Rated short-circuit making current Ima 31,5kA
Rated symmetrical interrupting current Isc 12,5kA
Electrical life short-circuit interrupting at rated current 200
Mechanical durability (the process defined as closing and opening) 30000
Operation temperature - 40°C + 55°C
Self-weight 100kg
Current metering Current transformers or Rogowski coils
Voltage metering 6x voltage dividers
Control system parameters
Rated voltage of the altering current power suply 230 VAC
Rated voltage of the internal system power suply 24 VDC
Degree of protection IP 54
Ambient temperature range -40°C +55°C
Possibility to install transmission modules GPRS/TETRA/NET-MAN/TRUNKING
Unladen maxx 40 kg

Recloser standards and have a certificate of conformity from the accredited body.

View, dimensions and construction of the switching unit

Budowa zespołu łączeniowego
Budowa zespołu łączeniowego
  1. stainless-steel housing of the recloser
  2. drive housing, under which is an electromagnetic drive
  3. safety valve
  4. lifting brackets
  5. resin isolator with voltage divider installed inside, covered with silicone rubber
  6. recloser interrupter installed inside the bushing isolator
  7. main common shaft for all three poles
  8. manual open and lock handle
  9. fast electromagnetic drive
  10. RX terminal strip
  11. Rogowski coil or current transformer
  12. MV cable connection
  13. lifting bracket for recloser installation on the pole
  14. visual position indicator

Dimensions and size

Wymiary i gabaryty zespołu łączeniowego
Wymiary i gabaryty zespołu łączeniowego

Schematic diagram

Schemat ideowy

Wiew, dimensions and construction of the control unit

Budowa zespołu sterowniczego
Budowa zespołu sterowniczego
Control unit housing made from aluminum sheet, powder painted
  1. controller protection SO-54SR-111-REK
  2. capacitors
  3. batteries
  4. operating mode switch: remote, local, reclosing off
  5. circuit breaker position indication
  6. local control switches
  7. live-line operation switch
  8. automatic reclosing switch (automatic service restoration)
  9. main protection 230 VAC with an arrester B + C and damage indication
Schemat zespołu sterowniczego
Additional information