PRODUCTS:
HV Switchgear
  Air Insulated Switchgear
(Up to rated voltage 15 kV)
 
  Single Busbar
(Horizontal drawout) / Horizontal isolation AH12
 
  Double Busbar
(Horizontal drawout) / Horizontal isolation AH12
  Compact Switchgear for compact Substation AH12/C
  Gas Insulated Switchgear (Up to rated voltage 36 kV)
 
  36 kV Gas insulated Switchgear
  15 kV Ring Main Unit
 
  15 kV Ring Main Unit with Switch fuse unit / VCB
  Change-Over Switch Cabinet
  RC snubbers
   
LV Switchgear
 
Transformers
Unit Distribution Substations
Substation Automations
Busduct
 
Projects & Services
 
 

RING MAIN UNIT (RMU)

Type AR12 with ring switches and Switch-Fuse/circuit breaker in SF6 insulated chamber.

 
 

Salient Features :

  • Free standing or Transformer mounted.
  • Indoor and outdoor use.
  • Built-in Earthing Switches for ring cables and Transformer.
  • Built-in cable testing facility.
  • High degree of operator safety.
  • Full Protection from external environment.
  • Single operating handle for all Switches.
  • Reduced maintenance.

TECHNICAL DATA
Ratings Unit

Ring Switch (Load Break Switch) Type: ARRS-12

Transformer Switch-Fuse (Load Break Switch) Type: ARTS 12

Vacuum Circuit Breaker

Type: AH12
Rated Voltage kV 12/15 12/15 12/15
Rated Current (IEC Rating) A 630 200 630
P.F. Withstand Voltage kV 28/38 28/38 28/38
Impulse Withstand Voltage kVp 75/95 75/95 75/95
Frequency Hz 50/60 50/60 50/60
Breaking Current kA - 20/25 ** 20/25
Mainly Active Load A 630 200 -
Closed Loop Current as per IEC 62271 - 103 A 630 - -
Cable Charging Current as per IEC 62271 - 103 A 25 25 -
Short-time Withstand Current for 3 sec kA 20 2.5 21
Short-time Withstand Current for 1 sec kA 25 3.15 25
Rated Peak Withstand Current kAp 62.5 8.2 62.5
Rated Peak Making Current kAp 62.5 50/65 ** 62.5
Fuse Rating A - Up to 160 -
Rated Busbar Current (IEC Rating) A Up to 1250
Minimum operating SF6 Gas Pressure Bar g 0.05

** Prospective value, the actual current being limited by fuse