1. 1
SF6 Ring Main Unit
RMR-12/24N Type
12kV ,. Up to 24kV,……
Provided Customized manufacture
High reliable, compact, environmental protection…
2008/6
Best solution for your power!
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1.Company Introduce
Wenzhou Rockwill Electric Co., Ltd is one of the leading high technical enterprises professional
deals in medium high voltage switchgear and components develop , manufacture and sales.
Located in NO.1 Fazhan Road, Wengyang Industrial Zone, Wenzhou, used to known as Yueqing
Real Electric Works(Registered in 1986), registered in 2008.We have more than 20 years
experiences in Medium & high voltage field. We strategically cooperate with worldwide high
reputation medium & high voltage switchgear manufacturer and research institute, successfully
developed series of medium voltage mutually; filled the blank in China. We also teamed up with
province grade intelligence high voltage switch laboratory, together developed new generation
intelligence simultaneous technical vacuum switch, electronic current transformer, digital
integrated substation etc. Through the cooperation we obtain plenty achievements and build up
experience technical team. Plentiful talent backup, advanced production equipment, perfect
quality control system and reverse inspection procedure are powerful guarantee of our reliable
product quality and high reputation.
Our high reputation due to provide high quality products and service to domestic and foreign
market, besides Chinese market, our products also widely sales to Middle Europe, Southeast
Asia,Africa market, etc. Beside plenty products on optional,we also provide full design solution
and technical support,you only need to tell us what you want, our engineer will design for you,
provide whole set solution accordingly . We have always insisted the faith on grow together with
customers, and to provide a safe, simply, green and efficient medium & high voltage switchgear
and components
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2. Summary
2.1 General
The RMR series is completely insulated SF6 Ring Main Unit, This product is in conformity with
the standards the GB/IEC standard and the design of a high safety combined switch cabinets.One
of the main components of circuit breaker and load break switch, high technical level, superb
technology, stable performance, safe and reliable operation.
RMR series SF6 Ring Main Unit will take several
functional units and connecting busbar assembly in sealed
SF6 gas box, without any live parts exposed, with
advantages completely insulated , live parts maintenance
free, small volume, compact structure, convenient
operation etc. . The stainless steel plate of cabinet with
3.0mm thick , which can effectively prevent moisture,
corrosion caused by salt spray; Products passed the
breaking and making test, dynamic thermal stability test,
sealing test and mechanical test etc, the maximum
guarantee the safety of persons and equipment. The cabinet
is suitable for indoor and outdoor installation, and it is not
affected by the external environment, with high
performance of anti harsh environment
RMR series SF6 Ring Main Unit is widely used in
industrial and civil ring network distribution system and
power supply terminal, especially suitable for small
Secondary distribution substation, urban residential district,
and other places
2.2 Standards and specifications
2.2.1 Switchgear manufacture
The switchgear complies with the following specifications in accordance with relevant IEC
publications:
----IEC62271-200 ----IEC62271-100
----GB3804-2004 ----GB3906-1991
----GB16926-1997 ----GB/T11022-1999
2.3 Operating conditions
2.3.1 Normal operating conditions Design to relevant standard, with the following limit values:
a)Air temperature: ±40 ; Daily average ≤25°C℃
b)Altitude above sea level: Maximum installation altitude: 4000m
c)Wind: less than 35m/s;
d)Earthquake intensity: no more than 8 degrees;
3. Main new advantages of RMR
3.1 The SF6 gas tank feature:
RMR use SF6 – gas (Sulphur hexafluoride) as insulation and
quenching medium.
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The SF6 is contained in a welded stainless steel tank, which is sealed for life.The pressure system
is defined as a sealed for life system with an operating life time exceeding 30 years. The leakage
rate is less than 0.1% per year. In order to ensure a reliable and tight welding, all welding work is
carried out by computer controlled robots.
Electrical and mechanical bushings penetrating the tank are clamped and sealed to the tank by
high quality O-rings.
The mechanical bushing has in addition a rotating shaft
which connects the shaft of the switch to the corresponding
shaft of the mechanism. The rotating shaft is sealed by a
double set of gas seals.
All SF6-tanks have to pass a leakage test before gas fill-ing.
Leakage test and gas filling are done inside a vacuum
chamber. The first step in the leakage test is to evacuate all
air inside both SF6-tank and vacuum chamber
simultaneously. Then the SF6-tank is filled with Helium.
Due to the characteristics of Helium this test will detect all
possible leakages. If the SF6-tank passes this test, the
Helium will be evacuated and replaced by SF6.The
SF6-tank has a degree of protection of IP65 and can be
immersed into water and still maintainable functions in a
satisfactory way.
4.Primary schemas and layout sheet
4.1 Main indoor application schemas & layout application
Combination CCC Combination VVV
Note:
All above combination dimension is same: 1020×750×1345mm.
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Combination CVC/CCV/CVV/VCV Combination CCF/CFC/CFF/FCF/CCF
Note:
All above combination dimension is same: 1020×750×1345mm.
4.2 Special required indoor application schemas & layout application
Combination CFV Combination CFF/FFF
Note:
If any special required to adding additional panels like: C,F,V, or metering unit , cable connector,
please consult with us before order.
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5. Standard module function and dimension
Type Type function Width(mm)
C Load break switch 325
F Switch-fuse combination 325
V/CB 3-position switch+VCB 325
M Metering module 700
Sv Bus bar section +VCB 650
Rest unit dimension is same: 325mm
Note:
All above combination dimension is same: 1020×750×1345mm.
6. Extension type with bushing
F + Side-extension bushing V + Side-extension bushing C + Side-extension bushing
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7. Technical Parameters
No Item Unit Data
1 Rated voltage 12/24
Dry
Power Frequency withstand voltage
Wet
42/50
2
Lightning Impulse withstand Voltage (peak value)
kV
75/65
3 Rated Current A 630/1250
4 Rated short circuit breaking current (peak) kA 20
5 Rated closed-loop breaking current A 630/1250(C)
6 Rated cable charging interrupting current A 50(C)
7 Rated line cable charging interrupting current A 10(C)
8 Rated off circuit transformer breaking current A 16
9 Rated making current (peak)
10 Rated withstand current (peak)
50/2.5(main
switch/grounding)
11 Rated short time withstand current
kA
16/20
12 Rated short time withstand time S 3/4
13 Mechanical life times C/F(2000)V(10,000)
14 Main busbar A 630/1250
14 SF6 rated pressure (20℃) MPa 0.014
15 SF6 Annual leakage rate % ≤0.05
16 Secondary circuit rated power voltage kV 2
17 Secondary citcuit 1min power frequency voltage V AC220/DC48/DC24
18 Enclosure IP65
19
Protection degree
Cabinet and operation
mechanism
IP3X
Note:
If any special required please consult with us before order. For example:
1, High current 1250A. 2, Big breaking current; 3, Higher insulation. Etc.
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8. Switch Device
Wide selection of reliable quality switching products are avaiable,the load break switch,vaccum
circuit breaker.
10.1 Load break switch
The load break switch is a 3-position switch disconnector and earthing switch using SF6 gas as an
arc quenching meduim,the switch positioning is close-open-earthed. In the open position the
switch satisfies the disconnector requirements.
3-position load break switch (closed,open,and earthed)
Spring mechanism consists of single spring
action, double spring operating mechanism. Among
them, the double spring operating mechanism used in
switchgear unit, can realize the automatic tripping trip.
10.2 Vacuum circuit beaker
RMR Vacuum circuit breaker has vacuum bottles as
interrupters of the current.In series with the
circuit-breaker main circuit is connected a 3-position
disconnector/earthing switch. The operation between
vacuum circuit breaker and disconnector/earthing
switch is mechanically interlocked.
Compact, simple structures and safe operation.
10.3 Fuse
By means of tripping device it operates as a switch-fuse combination. Two earthing switches are
equipped in both sides of the fuse-links in order to ensure the personal safety of operators.
Both earthing switches are operated in one operation.
The switch-fuse and earthing switch is mechanically
interlocked to prevent unauthorized access to the
fuse-links.
The lower cover which gives access to the fuse-link is
also mechanically interlocked with the earthing switch.
The fuse holder is sealed tightly,so it is anti electirc dust
and moisture.
Note: Fuse selection for transformer protection selection refer to IEC fuse standard.
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11. The accessories
11.1Gas pressure/density meter
Density meter with Low voltage pressure alarm General density meter
Each tank of RMU is equipped with density meter to monitor the gas pressure inside. The pointer
of the meter is in the green area, that means the normal pressure in the gas tank, if the pointer is in
the red zone, it means the pressure of the tank is low.
It is required to periodically inspect the density meter, to ensure the pressure in the normal range.
Additionally, density meters with low pressure alarm is also available as an option. The meter is
provided as the customer specified.
11.2 Type C Bushing
The connection of the HV-cables is made by cable Type
C bushings. See right side pictute.
The Type C bushings are made of cast resin epoxy with
moulded-in conductors.
This C type is used together with full-screened elbow
cable connectors which is an ideal solution for areas
with humidity or condensation problems is achieved.
11.3 Voltage indicator
Each unit is equipped with voltage indicator with
phase check outlet,which feature:
Stable performance,
High brightness,
Wide viewing angle,long life.
11.4 Fault indicator
Fault indicator is provided as an option
Fault indicator for detection of a short circuit,
single phase earth fault.
Accurate detection and clear indication.
Note:
Above components of RMU is standard equipped, any special requirement pls consult us.
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11.5 CT/Zero sequence CT
CT/Zero sequence CT are provided according to the
customer’s requirement.
a.Installed on external bushings when need.
CT should be earthed reliable,and open circuit of
secondary side is not allowed,or it will lead to severe
damage to the equipment and even dangers to the
individuals.
11.6 Elbow cable connector and relevant accessories
-Frontal Elbow Cable connectors
-Copper conductors
-Press cores
-Copper lugs
-Additional back cable connector optional
-Additional elbow connector type surge arrester
11.7 Operating Handle
The operating handle has two sides,for both Load break
switch,circuitBreaker,and earthing switch manual
operation,
11.8 Protection relay
RP260 protection device is numerical protection relay
with self-powered.
-OC/EF protection
-Fault report
-UV/OV protection
-Frequency protection
-Other required is discussable
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12. Dimension of Outdoor application RMU
Note:
Above is dimension for three unit combination, all the dimension about CCC, FFF,CCV, VVV,
CVV, CFV, FFV, CCF is same.
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13. Extension way by top connection
For normal Ring main unit combined by three unit together, above picture reference is shown us.
If special required more, pls consult us.
14. Technical service
Rockwill,China. Provide with best support,
If you have any question pls consult below.
Rockwill, CHINA. Tel: 0086-577-27869968
Rockwill, CHINA. Email: Rockwell@rockwill.cn