HSS-CM-Y604 A4(297X210)

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OPERATION of

CIRCUIT BREAKER

HSS-CM-Y604 A4(297X210)

PAGE: CB-2

PAGE

1. GENERAL : CB-3 2. RATINGS : CB-4 3. CONSTRUCTION

3.1 BASIC CONSTRUCTION : CB-5 3.2 INTERRUTER ASSEMBLY : CB-5 3.3 CONTROL BOX ASSEMBLY : CB-5 3.4 HYDRAULIC SYSTEM : CB-8

4. OPERATING PRINCIPLE

4.1 OPERATION PRINCIPLE OF CB – CLOSING OPERATION : CB-13 4.2 OPERATION PRINCIPLE OF CB – TRIPPING OPERATION : CB-16 4.3 CIRCUIT BREAKER – MANUAL BUTTON OPERATION : CB-18 4.4 CONFIGURATION OF ARC INTERRUPTION PROCESS : CB-19

5. RECOMMENDED HYDRAULIC OIL OPERATION MECHANISM

5.1 MAKER AND TYPE OF HYDRAULIC OIL : CB-20 5.2 APPLICATIONS OF HYDRAULIC OIL : CB-20 5.3 PROPERTIES : CB-20

C O N T E N T S

HSS-CM-Y604 A4(297X210)

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1. GENERAL The circuit breaker will be designed SF6 gas insulated, which features excellent arc-extinguishing performance and high dielectric strength and will be three phase isolated tank type.

1) The control mechanism will be provided with a controller, link mechanism for controlling the interrupter and oil dashpot.

2) The circuit breaker will have ability of three and single pole operation for reclosing system and will be completed with all necessary general purpose auxiliary relays for the following operations at the specified nominal control voltage of 220 Vdc.

a) A suitable trip-free device will be included to assure that the operating mechanism make

only one closing operation with each closure of the control contact device, even though the circuit breaker trips during the closing operation while the control circuit remains closed.

b) Once the closing control switch has been operated and the first device in the control scheme has responded, the circuit breaker mechanism will make one complete closing operation, even though the control switch is released before the closing operation has been completed.

3) The control system and power circuit will protected by no fuse breaker.

4) Operating mechanism

a) The accumulators of the circuit breakers will have sufficient capacity to permit not less than two positive close-open operation, starting at normal operating pressure, without assistance from the motor operation.

The operating mechanism will be damped in order to avoid the end of stroke impacts.

b) Manually operated device for tripping the circuit breaker without the aid of control voltage will be provided.

It will be protected against accidental operation and will be conveniently located for quick manual tripping of the circuit breaker.

For maintenance purposes, a manually operated closing devices will be furnished with each circuit breaker.

c) All operating boxes will be equipped with space heater and thermostat, humidistat to prevent condensation in the air system and in the control cabinet under the environmental conditions.

5) Each circuit breaker will be capable of successfully interrupting any type of fault current from rated continuous current to 100% of the rated interrupting current within 2 cycles.

Each circuit breaker will be capable of successfully interrupting any out of phase switching currents up to 25% of the normal interrupting capability.

HSS-CM-Y604 A4(297X210)

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6) All circuit breaker will be electrically and mechanically trip free.

7) The stationary and moving contact assemblies will be designed so that loading springs, retaining pins, and parts other than the main or arcing contacts do not form an essential part of the current carrying circuit.

8) The nominal control voltage will be 220 Vdc. The circuit breaker will be capable of operating within the following ranges. - CLOSING : 187 ∼242 Volts (85%~110%) - TRIPPING : 154 ∼242 Volts (70%~110%)

9) The CB will be fitted with electrical and mechanical anti-pumping devices.

2. RATINGS

Type 420 HCB 50

First-pole-to-clear-factor 1.3

Rated short circuit breaking current 40(50) kA rms

Rated short circuit making current 130 kA peak

Rated short line fault breaking current 45 kA rms

Rated out of phase breaking current 12.5 kA rms

Cable charging switching current 500 A

Line charging switching current 500 A

Rated short time withstand current 40(50) kA rms(1 sec)

Rated breaking time 2 cycle

Operating duty cycle O – 0.3sec – CO – 3 min – CO

-Lightning impulse withstand voltage(1.2 x 50µs)

·Phase to Earth, Phase to Phase

·Across Contacts

1425 kV peak

1425(+240) kV peak

- Switching impulse withstand voltage(250 x 2500µs )

·Phase to Earth, Phase to Phase

·Across Contacts

1050 kV peak

900(+345) kV peak

HSS-CM-Y604 A4(297X210)

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- Power frequency withstand voltage

·Phase to Earth, Phase to Phase

·Across Contacts

650 kV rms, 1min

815 kV rms, 1min

Operating method Hydraulic

No load opening time Less than 18 m sec

No load closing time Less than 120 m sec

Rated of rise of recovery voltage 2.0 kV / us

Trip coil current Less than 10 A

Close coil current Less than 5 A

Rated control voltage 220 Vdc

Rated SF6 pressure 0.6 MPa. G at 20 oC

Rated operating hydraulic pressure 320~340 kg/cm2.G

3. CONSTRUCTION

3.1 Basic construction (See FIG. CB-1)

FIG.CB-1 is the outline drawing of three-pole single throw operated type SF6 Gas Circuit

Breaker with the construction diagram of this breaker.

3.2 Interrupter assembly (See FIG. CB-2)

This interrupter is one of the break puffer-type and is accommodated in a grounded tank filled

with SF6 gas at a pressure of 0.6MPa.G at 20oC.

3.3 Control box assembly (See FIG. CB-1)

This control operating mechanism is provided with control mechanism assembly, operating

cylinder assembly, Accumulator and other apparatus to drive the interrupters.

HSS-CM-Y604 A4(297X210)

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FIG. CB-1 CONSTRUCTION DIAGRAM OF GCB

HSS-CM-Y604 A4(297X210)

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FIG. CB-2 CONSTRUCTION DIAGRAM OF INTERRUPTER

HSS-CM-Y604 A4(297X210)

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3.4 Hydraulic System

1) Structure of hydraulic system (FIG.CB-3 and FIG.CB-4)

The hydraulic system has the pressure generating device which is consist of the hydraulic

pump·electric motor, pressure control device which is consist of magnetic valve·safety valve·oil

pressure switch, oil control device which is consist of operating cylinder, MAIN valve and PILOT valve,

ACCUMULATOR, OIL Tank and connecting pipe.

2) Hydraulic control, low pressure alarm and re-make locking

Hydraulic pump control, re-make locking, make locking, low pressure alarm and trip locking could be

possible through the hydraulic pressure switch which is operates according to decrease and increase

in pressure of operating oil.

HSS-CM-Y604 A4(297X210)

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NO. DESCRIPTION NO. DESCRIPTION

1 OPERATING CYLINDER 12 MOTOR

2 MAIN VALVE 13 OIL LEVEL INDICATOR

3 PILOT VALVE 14 ACCUMULATOR

4 OPENING HOOK MECHANISM 15 RELIEF VALVE

5 CLOSE HOOK MECHANISM 16 HEATER

6 AUXILIARY SWITCH 17 OIL INJECTION VALVE

7 OIL PRESSURE GAUGE 18 CHECK VALVE

8 INDICATOR 19 MECHANICAL COUNTER

9 STOP VALVE

10 DASHPOT

11 OIL TANK

FIG. CB-3 HYDRAULIC MANIPULATOR CONSTRUCTIONAL

DRAWING

HSS-CM-Y604 A4(297X210)

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NO. DESCRIPTION NO. DESCRIPTION

1 CB 13 DRAIN PIPE

2 OPERATING CYLINDER 14 OIL INJECTION VALVE

3 AUXILIARY SWITCH 15 MAGNETIC VALVE

4 PRESSURE MANOMETER 16 FILTER

5 PRESSURE SWITCH 17 HYDRAULIC PRESSURE PUMP

6 MAIN VALVE 18 OIL LEVEL SWITCH

7 PILOT VALVE 19 ACCUMULATOR

8 HIGH PRESSURE PIPE 20 FILTER

9 SAFETY VALVE 21 RETURN PIPE

10 STOP VALVE 22 OIL

11 STOP VALVE 23 OIL LEVEL INDICATOR

12 MOTOR

FIG. CB-4 HYDRAULIC SYSTEM DIAGRAM

HSS-CM-Y604 A4(297X210)

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NO. DESCRIPTION NO. DESCRIPTION

1 MANUAL OPERATION BUTTON 10 SHAFT

2 SPRING 11 CAM

3 ROD 12 LEVER

4 SPRING GUIDE ROD 13 HOOK

5 HOOK 14 FITTING

6 HOOK 15 SPRING

7 LEVER 16 ARMATURE

8 MAKING HOOK SPOOL 17 MAKING COIL

9 SPRING 18 CORE

FIG. CB-5 MAKING HOOK CONSTRUCTIONAL DRAWING

HSS-CM-Y604 A4(297X210)

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NO. DESCRIPTION NO. DESCRIPTION

1 MANUAL OPERATION BUTTPN 10 BRACKET

2 ROD 11 SPRING

3 HOOK 12 CAM

4 TRIP COIL 13 SHAFT

5 CORE 14 LEVER

6 ARMATURE 15 FITTING

7 SPRING 16 HOOK

8 HOOK 17 LEVER

9 TRIP HOOK SPOOL 18 SPRING

FIG. CB-6 TRIP HOOK CONSTRUCTIONAL DRAWING

HSS-CM-Y604 A4(297X210)

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4. OPERATING PRINCIPLE OF HYDRAULIC MECHANISM

AntipvAntipv

Pilot valve

Pump/APump/A

Pilot valve

ManifoldManifold

Low Press.Chamber

Main valve

OO CC

Electric hook

(Opening)

Electric hook

Aux s/wAux s/w A

(Closing)

Accumulator

BCylinderCylinder

PistonPiston

C

- Red Color : High pressure side - Blue Color : Low pressure side

<Hydraulic Operating System>

4.1 Operation principle of CB - CLOSING Operation

When the closing coil is energized, closing electronic hook is excited. And then, armature is

attracted and hook is opened simultaneously. And the spool of closing pilot valve rises upside. So

high pressure oil is supplied to the main valve ‘A’ through closing amplification valve. According to

this process, ‘A’ gets high pressure and the spool of main valve moves to the left side. Operation

cylinder ‘B’ and ‘C’ become a condition of high pressure and the operation piston is moved to the left

as per difference of section area of piston shaft. Operation oil does not have compressibility and

pressure of operation oil is given by compressing N2 gas of accumulator.

For detail operation steps, refer to following sequential description of combination with circuit

breaker and hydraulic operation mechanism.

HSS-CM-Y604 A4(297X210)

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� Step 1 Trip status

� Step 2 Ready to close

HSS-CM-Y604 A4(297X210)

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� Step 3 In process of closing operation

� Step 4 Closed status

HSS-CM-Y604 A4(297X210)

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4.2 Operation principle of CB - TRIPPING operation

When the trip coil is energized, closing electronic hook is excited. And then armature is attracted

by magnetic force. And after hook is opened, the spool of opening pilot valve rises upside. According

to this process, the oil of high pressure of the main valve ‘A’ is drained through the open amplification

valve. The main valve ‘A’ becomes atmospheric pressure, therefore the main valve spool moves to

the right side and the operation cylinder ‘B’ becomes atmospheric pressure. At the same time, high

pressure is given to operation cylinder ‘C’ by the accumulator and operation piston moves to the right

side and opens the main contact. The operation oil drained from section ‘B’ by operation piston

passes through main valve and flows in low pressure chamber. And the accumulator always supplies

accumulator with operation oil as much as quantity of drained oil.

For detail operation steps, refer to following sequential description of combination with circuit

breaker and hydraulic operation mechanism.

� Step 1 Closed status

HSS-CM-Y604 A4(297X210)

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� Step 2 Ready to open

� Step 3 In process of opening operation

HSS-CM-Y604 A4(297X210)

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� Step 4 Opened status

4.3 Circuit breaker - manual button operation

The manual push-button switch has “open” (to divide trip with button) and “switches on” (switches on with

button), when presses down “open” the button, the installment operating lever rotation armature, started

the trip suspension hook. The circuit breaker or the fast earthing switch are at the trip condition. Also

presses down the switching button, the connection switches on the installment the operating lever

rotation armature, started has switched on the hook. The circuit breaker or the fast earthing switch are at

switch on the condition.

▶ Notice

￭ Before carrying on the manual button operation must confirm that circuit breaker or in fast

earthing switch main body box SF6 gas pressure after whether to achieve above the normal value, then starts to operate. When operates, since the reset mechanism operates fast, watch hands.

HSS-CM-Y604 A4(297X210)

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4.4 CONFIGURATION OF ARC INTERRUPTION PROCESS

HSS-CM-Y604 A4(297X210)

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5. RECOMMENDED HYDRAULIC OIL OF OPERATION MECHANISM

5.1 Maker and type of hydraulic oil

- Maker: Shell of DEA Oil Gmbh, Germany

- Type: AeroShell Fluid 41

5.2 Applications of Hydraulic oil

AeroShell Fluid 41is intended as a hydraulic fluid in all modern aircraft applications requiring a

mineral hydraulic fluid. AeroShell Fluid 41 is particularly recommended where use of a “super clean”

fluid can contribute to improvements in component reliability, and can be used in aircraft systems

operating unpressurised between -54℃ to 90℃ pressurized between -54℃ to 135℃.

5.3 Properties

PROPERTIES AeroShell Fluid 41 (MIL-H-5606G)

Oil type Mineral

Kinematic viscosity, ㎟/s

@ 100℃

@ 40℃

@ -40℃

@ 54℃

4.90min

13.2min

600max

2500max

Flashpoint, Pensky Martin closed cup℃ 82min

Pour point, ℃ -60max

Total acid number, mgKOH/g 0.20max

Evaporation loss 6hrs @71℃, %m 20max

Water content, ppm 100max

Relative density, @ 15.6/15.6℃ Report

Color Red

Particulate Contamination Number of particles per

100ml in size range

- 5 to 15 microns

- 16 to 25 microns

- 26 to 50 microns

- 51 to 100 microns

- over 100 microns

10000max

1000max

150max

20max

5max

Copper corrosion 2e max

Steel on steel wear, Scar diam, mm 1.0max

Rubber swell, L rubber % 19 to 30

HSS-CM-Y604 A4(297X210)

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PROPERTIES AeroShell Fluid 41 (MIL-H-5606G)

Corrosiveness & oxidation @135℃

- metal weigh change

- viscosity change @40℃, %

- acid number change, mgKOH/g

Must

-5 to +50

0.20max

Low temperature Stability 72hrs, @-54℃ Must pass

Shear stability

- viscosity change, @40℃

- acid number change

Must pass

0.2max