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Solid Insulated Ring Main Unit

 Solid Insulated Ring Main Unit
Product overview:

The HSIS-11(24) solid insulated ring main unit was developed by HCRT according to market demands which indicated that three-phase 50Hz systems with rated voltage of 11KV(24KV) were common. This unit has the following advantages: modular, high electrical performance, high environmental protection, and easy installation. By being equipped with intelligent controllers such as an FTU and other related equipment, this ring main unit can realize different levels of control, measurement and protection functions, in order to meet the various requirements of our customers.


The inside of this solid insulated ring main unit adopts a rotary fuse structure, which makes the replacement of the fuse cubicle type and making it extremely easy. The size of this unit is the smallest of all gas insulation cabinets, covering the least area, and it is eco-friendly for the power supply and distribution of urban users and residential applications.

Type and significance of the Ring Main Unit:
Technical parameters:
Parameters HSIS Solid insulated ring main cabinet HSIS(C) load-break switch HSIS(V) circuit breaker composite apparatus HSIS disconnecting, grounding switch
Rated voltage (KV) 11/24 11/24 11/24 11/24 11/24
Rated current (A) 630/1250 630/1250 630/1250 125 630/1250
Rated frequency (Hz) 50 50 50 50 50
Operation types vacuum vacuum vacuum vacuum vacuum
Arc extinguishing types Permanent magnet and spring Permanent magnet and spring Permanent magnet and spring Permanent magnet and spring spring
Power-frequency withstand voltage (KV) 42 42 42 42 42
48 48 48 48 48
Lighting impulse (KV) 75 75 75 75 75
85 85 85 85 85
Rated short-circuit breaking current (KA) 20 20
Rated short-circuit breaking current Breaking times 30 30
Rated short-circuit current (KA) 50 50 50 20
Rated short –circuit breaking current breaking times 5 5 2
Rated short-time withstand current 20 20 20 20
duration of rated short-circuit 4 4 4 4
Rated peak with stand current (KA) 50 50 50 50
rated cable-charging breaking current (A) 10 10
Take over current (A) 1750
Arc current (S) 0.5 0.5 0.5 0.5 0.5
partial discharge (pc) ≤20 ≤5 ≤5 ≤5 ≤5
Mechanical service life
(Permanent magnet mechanism and spring mechanism)
10000/30000 10000/30000 10000/30000 10000/30000 10000/30000
Switchgear dimensions 400*750*1450 400*750*1450 400*750*1450 400*750*1450 400*750*1450

-Full insulation and full enclosure.
-The ring main unit has flexible wiring schemes.
-It uses environmental friendly materials
-The unit adopts automatic control.
-It has clear operation interface: the operating sequence is linked with switch interlocks.
-The solid insulation outer surface covers the ground plane.
-The unit has excellent weather resistance
-The ring main unit has small size and compact structure.

Application environment:

-The maximum temperature: +50℃; minimum temperature: -40℃
-Humidity: daily average is no more than 95%, the monthly average is no more than 90%
-Seismic intensity: grade 8
-Altitude: ≤5000 meters

Module and operating instructions:

Circuit breaker module (V module)

-The circuit breaker module is used for the control and protection of lines and transformers, and has the following functions: overload, short circuit, fast power break, reclosing, under voltage protection and grounding protection.
Standard configuration:
-Circuit breaker switch cabinet (switch, electric / manual operating mechanism)
-Live displayer
-Grounding observation window
-Control box
-Cable plug observation window
-protective current transformer (2 pcs)
-Active (passive) overload protection device
Basic performance:
-vacuum extinction
-Permanent magnet mechanism and spring mechanism
-Mechanical interlock
-Three station isolation / grounding
Module size: 400*750*1450

Contact module

-The contact module can be matched with the related switch cabinet, to be connected with two bus lines, so that it forms a double bus connection, which improves the reliability of the power supply.
Standard configuration:
-11KV(24KV)/630A bus tie cabinet
-Live displayer

Load switch Modular (C Modular)

-The load switch modular is used for the control of inlet-outlet line cable, can break off the load current and short-circuit current.
Standard configuration:
-Load switch cabinet (switch, electric / manual operating mechanism)
-Live displayer
-Insulate ground observation window
-Control box
-Cable plug observation window
Basic performance:
-Vacuum extinction
-Rotating three station isolation / grounding, spring / permanent magnet operating mechanism
-Five mechanical interlock
Module size: 400*750*1450

Cable lifting (energizing) module (D module)

-The cable lifting module is a kind of bus bar cabinet, taking the bottom line as the busbar.
-It can also be used in metering outlet cabinets.
Standard configuration:
-Lifting cabinet
-Live displayer, insulate ground observation window
Basic performance:
-630 busbar
-Outlet line of cable box
-Cable plug observation window
Module size: 400*750*1450

High voltage metering module (M module)

-Measuring and recording the power supply.
Standard configuration:
-Metering cabinet
-11KV(24KV)/630A busbar
-Three phase PT (voltage transformer) 1 piece
-PT protection fuse
-2 sets of 630 cable plug
-CT (current transformer) 2 pcs
-Live displayer
Module size: 600*1000 *1450
Other optional configurations:
-Short circuit and ground fault indicator
-Current transformer and Meter
-Electrical operation (24/48VDC, 110/220V DC/AC)
-Auxiliary shock
-Cable accessories
-Transfer Switch
-Boundary switch control

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