Familiarization Of Dx Line Equipment

FAMILIARIZATION OF ELECTRICAL DISTRIBUTION LINE EQUIPMENT ENGR. ROMEO F. CEDIÑO, JR. Manager For Technical Services Department SORECO II

GENERAL DEFINITION: TRANSFORMER IS A DEVICE THAT TRANSFERS ELECTRICAL ENERGY FROM ONE ELECTRIC CIRCUIT TO ANOTHER WITHOUT A CHANGE IN FREQUENCY, DOES SO BY THE PRINCIPLE OF ELECTROMAGNETIC INDUCTION AND HAS ELECTRIC CIRCUITS THAT ARE LINKED BY A COMMON MAGNETIC CIRCUIT.

POWER TRANSFORMER • BY TYPE (SUBSTATION POWER TRANSFORMER): – STEP UP – STEP DOWN

* THE POWER TRANSFORMER IS CONSIDERED AS THE “HEART” OF THE TRANSMISSION AND DISTRIBUTION SYSTEM

POWER CIRCUIT BREAKERS

POWER CIRCUIT BREAKER DEFINITION: AN ELECTRICAL DEVICE CAPABLE OF: 1. CARRYING NORMAL LOAD CURRENT TO WHICH IT IS DESIGNED 2. MAKING AND BREAKING NORMAL LOAD CURRENT (CAPABLE OF MULTIPLE INTERRUPTION OF NORMAL LOAD CURRENT) 3. INTERRUPTING RATED FAULT CURRENT TO WHICH IT IS DESIGNED (CAPABLE OF MULTIPLE INTERRUPTION OF RATED FAULT CURRENT) 4. WITHSTANDING MOMENTARY FAULT CURRENT

MAIN FUNCTIONS/PURPOSES OF POWER CIRCUIT BREAKERS 1. INTERRUPT FAULT CURRENT AS QUICKLY AS POSSIBLE 2. ISOLATE AFFECTED CIRCUITS TO MINIMIZE DAMAGE TO OTHER EQUIPMENT 3. ENSURES CONTINUITY OF SERVICE

TYPES OF CIRCUIT BREAKER CLASSIFICATION ACCORDING TO ARC QUENCHING MEDIUM 1. OIL CIRCUIT BREAKER (OCB) 2. AIR CIRCUIT BREAKER (ACB) 3. GAS CIRCUIT BREAKER (GCB) 4. VACUUM CIRCUIT BREAKER (VCB)

TYPES OF CIRCUIT BREAKER CLASSIFICATION ACCORDING TO OPERATING MECHANISM 1. MAGNETIC OR MAGNEBLAST 2. PNEUMATIC 3. SPRING OPERATED 4. HYDRAULIC

METHODS OF ARC DISTINGUISHING 1. OIL CIRCUIT BREAKER A. COOLING THE ARC BY PUMPING OIL INSIDE THE INTERRUPTER B. ABSORBS HEAT BROUGHT ABOUT BY THE ARC C. GOOD INSULATING MEDIUM WHICH PREVENTS RESTRIKING OF INTERRUPTED CURRENT 2. AIR CIRCUIT BREAKER A. BLOWING OF AIR TO THE ARC TOWARDS THE ARC CHUTES 3. GAS CIRCUIT BREAKER A. PUFFING SF6 GAS TO THE INTERRUPTER AND ABSORBING HEAT BROUGHT ABOUT BY THE ARC. B. HIGH DIELECTRIC STRENGTH OF SULFUR HEXAFLOURIDE (SF6) PREVENTS RESTRIKING OF INTERRUPTED CURRENT. 4. VACUUM CIRCUIT BREAKER A. AIR WHICH CONTRIBUTES TO ARC PRODUCTION IS ABSENT, THUS NO ARC IS PRODUCED DURING CURRENT INTERRUPTION.

SAMPLE OF A TYPICAL WITHDRAWABLE TYPE

AIR CIRCUIT BREAKER

TYPICAL COMPONENTS OF AN OIL CIRCUIT BREAKER

SAMPLE OUTLINE OF A PNEUMATIC GAS CIRCUIT BREAKER

VACUUM CIRCUIT BREAKER (WITHDRAWABLE TYPE)

CUTAWAY VIEW OF A VACUUM CIRCUIT BREAKER

SWITCHGEARS

CONVENTIONAL SUBSTATION

GAS INSULATED SWITCHGEAR CROSS SECTIONAL VIEW

DISTRIBUTION TRANSFORMERS

Typical Distribution Transformer Primary H1 Bushing

Tap Changer (External/Internal)

Primary H2 Bushing

(At the Back)

Secondary

KVA Rating

Company Number

(X1, X2, X3)

Bushings

Nameplate (Hidden)

Symbols Used in Transformer Voltage Ratings NAME

Dash

Slant or Slash

Cross

SYMBOL

APPLICATION

-

To separate the voltage rating or ratings of separate windings.

/

To separate voltage to be applied or to be obtained from the same winding.

X

To designate separate voltages which can be obtained by reconnecting the coils of a winding in series or multiple combinations

EXAMPLES

7620 V

-

240/120 V

13200 GRDY / 7620 V 120 / 240 V

13200 GRDY / 7620 V 120/240 X 139/277 V

DT Nameplate Sample Primary Voltage Rating

Secondary Voltage Rating

Voltage Rating per tap position

KVA Rating

Polarity (Additive)

Schematic Diagrams

A Transformer Rated 13200 Grd.Y/7620 V

External Tap-Changers Operation

1. De-energize the DT 2. Loosen lock screw 3. Rotate switch to desired position 4. Tighten lock screw 5. Energize the DT

Lock Screw

Other Types of External Tap-Changers

Internal View of a DT With an External Tap-Changer TapChanger

Internal Tap-Changers Rotary Tap-Changers

Samples of DTs With Dual Voltage Tap Internal Tap changer

Dual Voltage Taps Always refer to nameplate for actual ratings.

Samples of DTs With Dual Voltage Tap Tap changer

Dual Voltage Taps

Changing the DUAL VOLTAGE TAP is done by transferring the connection of the primary lead

Samples of DTs With Dual Voltage Tap Changing the DUAL VOLTAGE TAP is done by transferring the connection of the outer end of the curved copper strip

Dual Voltage Taps

SECTIONALIZING EQUIPMENT

SECTIONALIZING Sectionalizing is the proper application of isolating and overcurrent protective devices to: 1. Facilitate manual and automatic line switching 2. Limit power interruption to the smallest practical segment of the line

RATIONALE The primary objective of sectionalizing is to minimize the extent and effect

of power interruption in a circuit through the proper application of isolating and protective line equipment.

EQUIPMENT USED FOR SECTIONALIZING • • • • •

Switch Fuse Recloser Sectionalizer Fault Indicator

SWITCH • A device for making, breaking or changing the connection in an electric circuit • It should be able to carry the normal load current continuously • It should also be able to handle abnormal or short circuit currents for short periods

TYPES OF SWITCHES • • • •

Disconnect Switch (DS) Air Break Switch (ABS) Load Break Switch (LBS) Remote-Controlled Line Switch (RCLS)

TYPES OF DISCONNECT SWITCHES 1. HORIZONTAL MOUNTING 2. VERTICAL MOUNTING 3. UNIVERSAL MOUNTING 4. CENTER BREAK

Disconnect Switch •

Plain knife-blade switch

•

Has no interrupter and is intended to be operated only when the circuit has been de-energized by some other means

•

Applications: primary line switch (PLS), disconnect switch

Air Break Switch •

A disconnecting switch equipped with an arcing horn

•

Can be operated with the circuit energized but carrying only charging or magnetizing current

•

The arcing horn helps extinguish the opening arc by extending it as the switch contacts open

Load Break Switch •

A disconnecting switch equipped with an interrupter

•

Can be operated when the circuit is energized and carrying normal load current

•

Can also be closed against a fault

Remote-Controlled Line Switch • An LBS that can be

operated remotely through SCADA

• It has the capability to

measure voltage, current and other circuit parameters

• If provided with the more

advanced type of electronic control, an RCLS can function like a sectionalizer

FUSE •

An overcurrent protective device which is placed in series in a circuit and has an element that melts during the passage of an overcurrent through it and thus interrupts the circuit

•

A fuse must be replaced after its operation

TYPES OF FUSES • •

•

Fuselinks Power Fuses – Type SMD-5 – Type SMD-20 – Type SMD-50 – Type SMD-100 Current Limiting Fuses (CLF)

Fuse Link •

Used in protecting distribution transformers, line capacitor banks, and lateral taps

•

Can be applied for fault currents up to 5,000 amperes and load below 4 MVA

•

Easily opened and closed using a telescopic hot stick

Power Fuse • Used in protecting transformer vaults and primary-metered services in high fault areas • Can be applied for fault currents up to 28,000 amperes and loads up to 12 MVA

Type SM-5 Power Fuse •

Can be applied for fault currents up to 28,000 amperes and loads up to 12 MVA

•

Uses a porcelain fuse holder

•

Can be opened with a telescopic hot stick but must be closed using a hook stick from a basket truck

Type SMD-20 Power Fuse •

Can be applied for fault currents up to 10,000 amperes and loads up to 8 MVA

•

Uses a fiber fuse holder

•

Can be opened and closed using a telescopic hot stick

Current Limiting Fuse (CLF) • Used in conjunction with a fuse link to protect distribution transformers in high fault areas as well as station service transformers • Has no time-current characteristic (TCC) and operates only at high fault current magnitudes • Has no external moving parts that could indicate its operation

DESCRIPTION An Automatic Circuit Recloser is a selfcontained device with the necessary intelligence to sense an overcurrent condition, interrupt the current flow, and then after a predetermined time delay, recloses automatically to reenergize the line. If the fault is permanent, it locks open after a pre-set number of operations thus isolating the faulted portion from the main part of the system.

RECLOSER •

A self-contained device with the necessary intelligence to sense an overcurrent condition, interrupt the current flow, & then after a predetermined time delay, recloses automatically to reenergize the line.

•

If the fault is permanent, it locks open after a pre-set number of operations thus isolating the faulted portion from the main part of the system.

RECLOSER CLASSIFICATIONS 1. Phase Single-phase or three-phase

2. Control Hydraulic or electronic

3. Interrupters Oil or Vacuum

4. Insulation Oil , Air or Epoxy

SINGLE-PHASE RECLOSERS •

Used to protect single-phase lines such as single-phase laterals

•

Can also be used on threephase circuits where the load is predominantly single-phase

•

Examples are the Type D (15.5 kV) and DV (38 kV) Kyle Reclosers from Cooper Power Systems

THREE-PHASE RECLOSERS 1. Triple-Single tripping (Ex. NOVA Type TS reclosers)

2. Three-phase tripping (Ex. Type KFME, WE, WVE, VWVE reclosers)

TYPES OF CONTROL 1. Hydraulic Control • •

Built as an integral part of the recloser Overcurrent is sensed by a trip coil that is connected in series with the line. When the overcurrent flows through the coil, a plunger is drawn into the coil to trip open the recloser contacts.

•

Timing and sequencing are accomplished by pumping oil through separate hydraulic chambers or ducts.

TYPES OF CONTROL 2. Electronic Control •

•

•

More flexible, more easily customized and programmed, and many have advanced protection, metering, and automation functionality. Line current is sensed by special sensing current transformers in the recloser The electronic control is housed in a cabinet separate from the recloser and conveniently permits changes to operational settings.

TYPES OF INTERRUPTING MEDIUM 1. Oil Interrupters •

•

Reclosers using oil for current interruption use the same oil for basic insulation. Some reclosers with hydraulic control also use the same oil for timing and counting functions.

TYPES OF INTERRUPTING MEDIUM 2. Vacuum Interrupters •

•

Vacuum interrupters provide fast, low-energy arc interruption with long contact and interrupter life, low mechanical stress, and maximum operating safety. With arc interruption taking place in a vacuum, contact and interrupter life far exceeds other interrupting media.

OPERATING LEVERS & INDICATORS 1. Manual Operating Handle • A yellow lever that is used to manually trip the recloser • For the Type DV recloser, this is also used to close the recloser. • For the Type KFME, WE, WVE & VWVE reclosers, this is used for manual tripping & to override the controls to keep the recloser open. This cannot be used to manually close the recloser but must be in the closed position (up) before the recloser contacts can be closed.

OPERATING LEVERS & INDICATORS 2. Contact Position Indicator • A red flag that is also linked to the interrupter mechanism but independent of the yellow handle • It drops down from under the sleethood when the interrupter contacts are open.

OPERATING LEVERS & INDICATORS 3. Operations Counter • Cumulatively records each time the recloser opens.

4. Non-reclosing Lever • Found on Type DV reclosers, this sets the unit to one shot to lockout after fault interruption

THE KYLE TYPE DV HYDRAULICALLYCONTROLLED RECLOSER Specifications Summary Nominal System Voltage (kV)

24.9 - 34.5

Maximum Rated Voltage (kV)

38

BIL (kV)

150

Max Continuou Current

560

Max Interrupting Rating (Sym.) Interrupting Medium Control Type

8000 Oil Hydraulic

THE KYLE TYPE DV RECLOSER

Construction features, operating levers, and indicators for the Type DV Recloser

THE KYLE TYPE DV RECLOSER Operating Levers and Indicators The DV Reclosers’ sleet hood, showing the manual operating handle, nonreclosing lever and contact position indicator. Also found under the sleet hood is the operations counter.

THE KYLE TYPE DV RECLOSER Major Components 1. 2. 3. 4. 5. 6. 7.

Arc interrupting assembly Closing solenoid Closing solenoid contactor Hydraulic integrator assembly Series trip solenoid Time-delay unit Head mechanism

THE KYLE TYPE DV RECLOSER

Manual Closing of a De-energized Type DV Recloser

THE KYLE TYPE KFME ELECTRONICALLYCONTROLLED RECLOSER Phase

3

Nominal System Voltage (kV)

2.4 - 14.4

Maximum Rated Voltage (kV)

15.5

BIL (kV)

110

Max Continuou Current

400

Max Interrupting Rating (Sym.)

6000

Interrupting Medium Control Type

Vacuum Electronic

THE KYLE TYPE KFME RECLOSER Operation

• Tripping & closing are initiated by signals from the electronic control • When currents in excess of the programmed minimum-trip value are detected in one or more phases, a signal from the control actuates a solenoid in the operating mechanism to trip the opening springs & open the interrupter contacts

Form 3A Control

Form 4C Control

THE KYLE TYPE KFME RECLOSER Operation

• Closing energy and the force to charge the opening springs is supplied by a closing solenoid energized from the source side of the recloser

THE KYLE TYPE KFME RECLOSER Operation

• Arc interruption takes place within the 3 sealed vacuum interrupters. • Oil is used for electrical insulation, but is not involved in arc interruption.

THE KYLE TYPE KFME RECLOSER Operating Levers and Indicators Contact position indicator

Non-reclosing lever

Operations counter

Manual operating handle (yellow)

THE KYLE TYPE KFME RECLOSER Electronic Control

Form 3A Control

• All operating parameters, like phase- and groundfault minimum trip levels, TCC selection & sequence of recloser operation are done via the electronic control • The Form 3A control is a solid-state electronic type while the Form 4C is a microprocessorbased control type

Form 4C Control

THE KYLE TYPE KFME RECLOSER

Typical Pole Installations

THE TYPE WE, WVE & VWVE RECLOSERS Operation • Closing energy & the force to required to charge the opening springs is supplied by a closing solenoid • Oil interrupters are used in WE & WVE. Vacuum interrupters are used in VWVE. • All are oil-insulated.

WE Recloser

VWVE Recloser

THE TYPE WE, WVE & VWVE RECLOSERS

Untanked view of Type WE recloser. Construction of WVE is similar.

THE TYPE WE, WVE & VWVE RECLOSERS

Untanked Type VWVE vacuum recloser

THE TYPE WE, WVE & VWVE RECLOSERS Manual Operating Lever & Indicator Yellow manual operating (trip-and-reset) handle • Used to manually trip the recloser & override the control to keep the recloser open

Contact position Indicator

• A red flag labeled OPEN independent of the yellow handle • Drops down from under the sleethood when the interrupter contacts open

THE TYPE WE, WVE & VWVE RECLOSERS Electronic Control • As with the Type KFME recloser, all operating parameters for the Type WE, WVE & VWVE reclosers are provided by the electronic control • The controls used by MERALCO are the Form 3A solid-state electronic control & the Form 4C & Form 5 microprocessor-based controls

Form 3A Control Form 4C Control

Form 5 Control

Type WE & WVE Reclosers in service

FAULT INDICATOR A device that indicates fault current flow Senses the magnetic field caused by the current flowing through the conductor Classified either as manual reset or automatic reset

SECTIONALIZERS

DESCRIPTION A SECTIONALIZER is a self-contained electrical device that interrupts its load side after sensing the passage of a predetermined number of successive fault currents and the corresponding trippings of the backup device at its source side.

SECTIONALIZER •

A self-contained electrical device that interrupts its load side after sensing the passage of a predetermined number of successive fault currents & the corresponding trippings of the back-up device at its source side

•

It opens during the open interval of the backup device

OPERATION • It opens during the open interval of the backup device • It does not interrupt fault current but can be closed into a faulted line • It can be used to interrupt normal load current • Once open, the sectionalizer will remain open until manually closed

The Type GW Sectionalizer

OPERATING DATA Phase-Minimum-Actuating Current (Amps)

BASIC SECTIONALIZER RATINGS Nominal Voltage Rated Maximum Voltage BIL Continuous Current Rating Rated Symmetrical Interrupting Current Rated Making Current, Asymmetrical Momentary Maximum, Asymmetrical

34.5 kV 38 kV 150 kV 400 A 880 A rms 15000 A 15000 A

16, 24, 40, 56, 80, 112, 160, 224, 256,

296, 320, 448, 640, 768, 896 Ground-Minimum-Actuating 3.5, 7, 16, 20, 28, Current (Amps) 40, 56, 80, 112, 160, 224, 320, 384, 448, BLOCK Number of Counts to Open 1, 2, 3 Count Resest (Seconds) 15, 30, 60, 120, 180 Phase Actuating Level X1, X2, X4, X6, X8, Multiplier (Inrush Restraint) BLOCK Phase Inrush Reset (Cycles) Ground Inrush Reset (Seconds)

5, 10, 15, 20 0.3, 0.7, 1.5, 3, 5

A Pole-mounted Type GW Sectionalizer

A Pole-mounted Type GW Sectionalizer

This sectionalizer is installed on an openwye primary lateral

External Features of Kyle Electronically Controlled Sectionalizer

Internal Details of the Type GW Sectionalizer

Operating Mechanism and Electronic Control

MANUAL OPERATING CONTROLS

The sectionalizer’s manual operating controls are located on the underside of the operator mechanism housing placed on one side of the sectionalizer’s tank.

AUTOMATIC VOLTAGE REGULATORS

Automatic Voltage Regulator • A tap-changing autotransformer with the ability to continuously monitor its output voltage and automatically adjust itself by changing taps until the desired voltage is obtained. • It regulates line voltage from 10% raise (boost) to 10% lower (buck) in 32, approximately 5/8 steps.

Reasons for Installing AVRs • To improve system voltage • To improve quality of service • To meet regulatory standards

Effects of AVRs on Voltage Problems Problems Solved by AVRs • Undervoltage • Overvoltage • Unbalanced voltage

Problems Not Solved by AVRs • Voltage sags • Voltage swells • Voltage flickers/fluctuations

Sample AVR Installation (Pole Mounted)

Sample AVR Installations (Platform Mounted)

MAJOR COMPONENTS OF AN AVR 1. S (Source) Bushing

1

4

2

5

2. L (Load) Bushing 3. SL (Neutral) Bushing 4. Series Arrester 5. Position Indicator 6. Electronic Control

6

3

MAJOR COMPONENTS OF AN AVR Position Indicator • Has a pointer mechanically connected to the tapchanging switch • Indicates the actual position of the tap-changer through the yellow pointer • Indicates the maximum & minimum positions attained during raise & lower operations through its drag hands. • Allows load bonus setting of the regulator

MAJOR COMPONENTS OF AN AVR Series Arrester • A bypass arrester connected across the series winding between the S & L bushings. • Limits the voltage developed across the series winding during lightning strikes, switching surges & line faults.

Typical Features of an Electronic Control 1. Voltage Level Selector 2. Bandwidth Selector 3. Time Delay Selector 4. Band-edge Indicator 5. Line Drop Compensation Selectors 6. Neutral Indicating Light 7. Drag hand Reset/Neutral Light Test Button 8. Internal/External Power Switch

Typical Features of an Electronic Control 9.

Control Switch

10. External Power Terminals 11. Voltmeter Terminal 12. Motor & Panel Fuses 13. Operations Counter 14. Data Port 15. LCD Display 16. Keypads

The Cooper/McGraw Edison VR-32 Step-Voltage Regulator

CONTROL TYPES 1. CL-2 / CL-2A 2. CL-4C 3. CL-5A

Cooper AVR with a CL-2A Control

Cooper AVR with a CL-4C Control 1 2 3 4 5 6

Input Voltage: 80 - 170 V 45 - 65 Hz

LCD Display Keypad Data Port Power Switch Voltmeter Terminals External Power Terminals 7 Panel Fuse 8 Differential Voltage Fuse 9 Motor Fuse 10 Manual RAISELOWER Switch 11 AUTO/REMOTEOFFMANUAL Switch 12 Neutral Lamp TestDrag Hand Reset Switch 13 Neutral Indicating Light

Cooper AVR with a CL-5A Control

Input Voltage: 80 - 137 V 45 - 65 Hz

Cooper AVR Bank with a CL-5E Control

Nameplate of a Cooper VR-32 AVR

The GE Type VR-1 Step-Voltage Regulator

CONTROL TYPES 1. VR-1 2. SM-3

The Siemens Type JFR Step-Voltage Regulator

A 250 kVA, 7.62 kV Type JFR AVR with an MJ-3A control

The Siemens Type JFR Step-Voltage Regulator

A 400 kVA, 19.92 kV Type JFR AVR with an MJ-XL control

Nameplate of a Siemens Type JFR AVR

Line Capacitors

CAPACITOR

• A device for introducing a capacitive reactance in a circuit to counteract the effects of inductive reactance • It reduces the impedance of a circuit with a consequent reduction in the voltage drop and an improvement in the PF • By reducing the current required to supply a load, it decreases losses in a circuit

SAMPLE 200 KVAR, 13200 V, CAPACITOR UNIT

CAPACITOR BANKS

FACTORY-ASSEMBLED BLOCK WITH HORIZINTALLY MOUNTED CAPACITOR UNITS

ADVANTAGES OF HAVING A CAPACITOR BANK INSTALLATION 1. RAISE AND LOWER VOLTAGE WHEN NEEDED 2. RAISE VOLTAGE ON SOURCE SIDE 3. REDUCES LOSSES IN THE SYSTEM 4. REDUCES THERMAL LOADING 5. RAISES SYSTEM LOADING CAPABILITY

TYPES OF CAPACITOR BANKS Series Capacitor Bank

• • •

Connected in series with the line Used to compensate for the reactive voltage drop in the circuit Typically used in low-voltage, heavycurrent applications such as furnaces & welders, to compensate for the voltage drop in the conductors

Shunt Capacitor Bank

• • •

Connected in parallel with the load Used to correct the component of current caused by inductive loads Typically used for PF correction

BENEFITS DERIVED FROM SHUNT CAPACITOR BANKS 1. Released Capacity

- due to PF improvement kW

kVA2 kVA1

kVAR2 kVAR1 CkVAR

2. Voltage Rise

- due to reduction in line impedance

3. Loss Reduction

- due to reduction in line impedance

TYPES OF CAPACITOR CONTROL 1. Fixed 2. Time 3. Voltage 4. Current 5. Power Factor 6. KVAR 7. Temperature

GUIDELINES IN HANDLING CAPACITOR BANKS 1. Before placing a capacitor bank in service,

inspect individual units for bulged or cracked tanks. Proper care should be exercised in handling capacitor units to prevent damage to or denting of capacitor case.

2. Before working upon capacitor units, the

capacitor bank must be allowed to stand at least five (5) minutes after disconnecting from source of power, after which it shall be short-circuited and grounded before work is started.

ENERGIZING & DE-ENERGIZING LINE CAPACITOR BANKS Always use the capacitor oil switch when energizing & de-energizing a capacitor bank. When the oil switch is inoperable, the following shall be observed:

1. Closing of FCOs shall be done only while the line is de-energized

2. For line capacitor banks installed on 13.8kV

circuits & below, opening of FCOs shall be done with the use of load buster

3. For line capacitors installed on 34.5kV circuits, opening of FCOs shall be done only when the line is de-energized

Cooper’s Type TSC Three-Phase Oil Switch Nominal System Voltage Rated Maximum Voltage Rated Momentary Current Rated Making Current Capacitive Continuous Current

34.5 kV 38 kV 12000 A 12000 A 135 A

Type TSC Oil Switch Operation

1. The oil switch is manually operated by means of the red handle under the sleet hood. Pulling down the handle will either open or close the switch depending upon its previous position. 2. A disc-type contact-position indicator shows the switch position.

Type TSC Oil Switch Operation 3. When the operating handle is pulled down, the manual reset lever is also pulled down.

4. When the operating handle is released, it automatically returns to its up position under the sleet hood. 5. The manual reset lever, however, must be returned to its up position before the motor circuit is armed & the switch is returned to remote electrical control.

Cooper’s Type NR Single-Phase Oil Switch

Nominal System Voltage Rated Maximum Voltage Rated Momentary Current Rated Making Current Capacitive Continuous Current

14.4 kV 15 kV 9000 A 9000 A 200 A

Manual Operation of the Type NR Oil Switch

The oil is manually opened & closed by operating the yellow handle under the sleet hood.

End of Presentation Thank You!