www.Entec-USA.com

User Manual www.Entec-USA.com

Date: June 2018

25.8kV Solid Dielectric Load Break

With SEL-751 Patent Pending Control Technology

Version 1.0

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ENTEC ELECTRIC & ELECTRONIC CO., LTD.

Table of Contents

1. General Information Page 3

2. Ratings Page 3

3. Characteristics Page 4

4. Construction Page 4

5. Operation Page 6

6. Maintenance Page 9

7. Precautions Page 11

8. Installation Drawings and Phasing Notes Page 13

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1.0 General Information

Pole mount Solid Insulated Load Break Switch (LBS) is rated up to 25.8kV suitable

for most power distribution grids in the United States. The LBS features Vacuum

Interrupters securely encapsulated with molecular-composite polymer and,

a Stainless-Steel tank containing the operating mechanism. The LBS

provides superb feeder management and fault isolation.

The LBS must be installed and applied within manufactured ratings.

CAUTION: Read name plate ratings to assure equipment application

conforms with system characteristics. DO NOT exceed LBS ratings on

name plate.

2.0 Ratings

2.1 Voltage Ratings (kV) USA Standard

Description 12 kV 25.8 kV

Maximum Voltage 12 kV 25.8 kV

Basic Impulse Level 75 kV 150 kV

2.2 Current Ratings (Amperes)

Description 12 kV 25.8 kV

Continuous Current 630 A 630 A

Short Circuit, Symmetrical RMS 20 kA 12.5 kA

Making Current, Asymmetrical Peak 50 kA 32.5 kA

2.3 Mechanical Duty Ratings

Description 12 kV 25.8 kV

No-Load Operations: Open/Close 5000 5000

Ops @5% of Cont. Rated Amps 200 200

Ops @100% of Cont. Rated Amps 20 20

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3.0 Characteristics

3.1 Capability

Polymer encapsulated vacuum interrupters provide a superior maintenance-free

alternative to SF6 technology. The LBS is optimized for power distribution

application.

3.2 Simple Operation

The LBS features a secure handle-lock mechanism to safeguard personnel and

equipment. The handle lock is operated via hot stick. Remote Open/Close

operation is possible from the pole-mounted control, and manual Open/Close is

simply performed with a hot stick.

3.3 Mechanical Integrity

Vacuum technology and molded polymer insulation provide years of superior

operation without high maintenance of SF6 gas. A stainless-steel tank houses

the primary operating mechanism with maximum protection from the elements.

LBS is a quality product conforming to IEC 62227-103 standards.

3.4 Safety

LBS provides safe and dependable switching for power grids. Three phase

radial sectionalizing and loop switching are possible with local control via central

Scada dispatch.

4.0 Construction

4.1 Tank

LBS tank is fabricated with durable stainless-steel and sealed for maximum

weather protection.

4.2 Handle Lock

A mechanical locking mechanism is provided to secure the LBS in Open position

while workmen are present. The lock maintains Open position and blocks

accidental Closing. Operators can easily view and/or operate the Yellow handle

from ground level.

4.3 Superb Arc Extinguishing Interrupters

LBS utilizes high-grade vacuum interrupters for superior arc suppression and long-

life operation.

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4.4 Moisture-Guard

"Zeolite" is used inside the LBS tank to maintain low humidity for the operating

mechanism even in harsh and humid locations.

4.5 Operation Mechanism

At the heart of every LBS is a spring-charged mechanism to Quick-CLOSE and

Quick-OPEN the mechanism. The operation is performed manually via hot-stick or

by motor control. Automated applications using the modernized smart-control

make the LBS an excellent choice for radial sectionalizing and distribution

automation.

4.6 Molded Epoxy Bushings

Molded polymer bushings are now state of the industry and standard for the LBS.

Entec utilizes a custom molding process to yield high-quality bushings, and all

bushings meet stringent quality standards.

4.7 Painting

Each LBS receives two coats of epoxy-grade industrial paint to assure the unit

weather protected for years of operation even in harsh environmental conditions.

Figure 1. Insulated Load Break Switch

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Figure 2. NEMA 4X Control Cabinet

5.0 Operation

5.1 Manual Operation

CLOSE Switch: Pull downward on the right-side rocker Handle. Internal spring

resistance is normal before mechanism “snaps” over center and operates the

switch. Visual indicator will show ON (Switch is CLOSED).

OPEN Switch: Pull downward on the left-side rocker Handle. Internal spring

resistance is normal before the mechanism “snaps” over center and operates the

switch. Visual indicator will show OFF (Switch is OPENED).

5.2 Handle Lock Operation

With the switch OPEN or CLOSED, use a hot stick to pull down the Yellow ring to

deploy a locking pin that blocks the rocker handle. Rocker handle will not travel in

either direction with Handle Lock applied, and all switch operations (Manual, Local

Control and Remote Automation) are all blocked with Handle Lock applied.

Unlock: Use hot stick and push upward raising the ring.

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5.3 SEL-751 Electronic Control Operation

The 751 control is housed in a NEMA 4X cabinet suited for harsh environments

and reliable operation. As with all electronic smart controllers, electric power is

required. The cabinet contains a 24V DC industrial power supply and charge

system that maintains continuous control during powerline blinks, and the 16Ah

battery provides ten-hours reserve to manage longer outages.

The LBS includes a custom SEL-751 sectionalizer control with innovative smart-

logic and patent pending technology. Known as LBS-751, this new unit

modernizes traditional applications for enhanced power system protection. Simply

input three basic setpoints, and factory programming does the rest. See “Quick

Start Guide” for step-by-step setup instructions.

1) Installation

• Secure cabinet to pole with thru-bolts and bond to equipment ground.

• AC and DC disconnects are located on top DIN rail. Confirm switches

are open.

• Inspect batteries and battery box for damage. Replace with like-kind if

damage is detected. (Enersys XE16)

• Fasten battery connector to apply 24V DC.

• Install Scada device if desired using 24V DC customer terminals

provided (Fig.4). Use knockout in bottom of cabinet for surge protection

and coax.

• Secure LBS control cable to cabinet. Tighten until solid “click” is felt

indicating cable is properly connected.

• Remove knockout in bottom of cabinet, install raceway for 120-240V AC

power, pull 12AWG wire and connect power to ACH and ACN terminals.

Bond AC Ground to GND terminal. (Fig.4)

• Check AC terminals with meter to verify proper voltage.

• Check AC and DC voltage at respective disconnect switches. Close

disconnects when ready.

• 751 will power-up for operation.

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2) Front Panel

Figure 3. SEL-751 Front Panel

LOCKOUT

ENABLED

HANDLE LOCK

DIAG FAIL

BATT FAIL

AC PWR FAIL

PB

01

PB

02

PB

03

PB

04

SECTIONALIZERCONTROL

A

B

C

D

NORMAL OPERATING LIGHTS

A. SECTIONALIZER ENABLED LED ON

B.

C. BLOCK CLOSE LED INDICATES PUSH BUTTONS LOCKED.

UNLOCK TO ENABLE CLOSE BUTTON.

D. RED LED ON = SECTIONALIZER SWITCH CLOSED

PUSH BUTTONS LOCK & BLOCK CLOSE LED’S ON (DISABLES

CLOSE BUTTON; TRIP BUTTON STILL LIVE)

Patent Pending

Technology

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Figure 4. Customer Connections, Fuses and Terminal Blocks

6.0 Maintenance

6.1 LBS

LBS is designed for industrial use in harsh environments and years of maintenance

free operation. For optimum results follow professional installation standards such

as REA specs, utility framing standards or similar guidelines maintaining safe

clearances, wildlife precautions and sound operating procedures. Inspect all

connections, clearances and grounding prior to energizing LBS. Periodical follow-

up inspections should be performed at regular intervals per Owner’s preventive

maintenance schedule. Manufacturer recommended inspections should be

performed annually to assure the LBS installation is in safe working condition.

Thoroughly examine all connections, clearances, grounding and control cabinet.

6.2 Control Cabinet

1) Battery System

The 751 control incorporates an industrial charger with diagnostic alarms. The

following conditions are monitored continuously:

• Battery Fail – UPS measures voltage and automatically disconnects the

battery if voltage decreases below 22V DC. If battery voltage is below 21V

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DC the Battery Fail LED will turn RED on front panel. This condition is

mapped in ModBus registers for Scada viewing.

MobBus 02h Read Coil: 306 (Battery Fail)

Modbus 03h Holding Register: 169 Bit-2 (Battery Fail)

• AC Power Fail - the power supply detects AC Power Fail. LED alarm

appears on the 751, and pre-assigned ModBus user table.

MobBus 02h Read Coil: 305 (AC Power Fail)

Modbus 03h Holding Register: 169 Bit-1 (AC Power Fail)

WARNING LBS will not operate correctly with Battery Fail.

WARNING

Battery will deplete and control will shut down after ten-hours. LBS will not operate past ten hours without AC power.

2) Fuses (Fig.4)

• FNM-5A 24V Power Supply for 751, Scada and Digital Inputs

• FNM-20A 24V Battery for LBS Switching Motor

2) Recommended Maintenance

• Install Telemetry Scada provides remote monitoring and the earliest

and most dependable alarm detection. Technicians will have more response

time to assure LBS-751 remains healthy and operating properly. Use Scada

host software to log alarms and alert technicians for Battery Fail and AC

Power Fail. Scada surveillance will assure LBS-751 is healthy and

dependable.

Perform 3-year site inspections. Inspect fuses, batteries, charge system and

751 status lights. Test door latch and close cabinet securely. Examine high

voltage clearances near LBS and poleline hardware. Inspect AC control

power connections, drip loop conductors and disconnect enclosure. Finally,

inspect all bonding connections and pole ground integrity.

• Without Telemetry Manufacturer recommends performing annual

inspections for units without Scada. Check fuses, batteries, charge system

and 751 status lights. Test door latch and close cabinet securely. Examine

high voltage clearances near LBS and poleline hardware. Inspect AC control

power connections, drip loop conductors and disconnect enclosure. Finally,

inspect all bonding connections and pole ground integrity.

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7.0 Precautions

7.1 General

LBS is designed and manufactured to specific ratings and compliance-tested to

meet IEC standards. Manufacturer performs strict production tests to assure

equipment will operate safely within ratings displayed on the permanent equipment

label. Refer to 2.0 Ratings on page 3.

WARNING

Equipment will perform to design ratings only when properly installed, properly

maintained and properly operated. The LBS should be installed, maintained and

operated by Qualified Personnel only. Failure to install or operate the LBS within

design ratings may result in serious equipment failure and serious injury or death.

WARNING

LBS is not rated to open continuous current exceeding rated design. LBS WILL

NOT CLEAR FAULT CURRENT. DO NOT ATTEMPT TO BREAK FAULT

CURRENT EXCEEDING CONTNUOUS CURRENT RATING. Explosion, serious

equipment failure and serious injury or death may result.

WARNING

Hazardous Voltage. Contact with voltage may cause burns, shock, serious injury

or death. DO NOT rely on visual indicators including but not limited to: Rocker

Handle, Visual Position Indicator, Handle Lock, Control Lights and/or Scada

Signals. To safely remove voltage Qualified Personnel must provide “visual

opening” such as removing Hot-line connections, opening mechanical disconnects,

etc and verify the circuit is de-energized using appropriate test equipment and safe

testing procedures. Failure to de-energize voltage may result in contact with

voltage causing burns, shock, serious injury or death.

WARNING

Securely bond equipment to ground. LBS bushings contain internal voltage

measurement sensors which terminate to tank ground. DO NOT disconnect

equipment ground while energized. High voltage may result on ungrounded

equipment connection while energized. Contact with ungrounded equipment may

result in contact with voltage causing burns, shock, serious injury or death.

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7.2 Inspection

1) Unpack LBS, control and accessories. Inspect items for damage during

transit, and report damage to supplier.

2) Inspect LBS mounting frame for mechanical integrity. Verify all bolts are

present and torqued.

3) Operate LBS several times manually (CLOSE & OPEN). Verify spring

resistance, free travel and proper movement.

7.3 Equipment Handling

1) Unpacking

Exercise care while unpacking LBS, control and accessories. Control cabinet

is equipped with sealed battery for stand-by operation. Use caution while lifting

control cabinet. Inspect battery for secure installation. Use caution storing

cabinet on back or bottom (normal upright position). Cabinet should not be

placed face down, sideways or upside down.

2) Installation

a) After inspecting mounting frame and frame bolts, use lifting lugs to move

LBS. Unit weights approximately 300 lbs.

b) Electrician: Securely bond equipment ground before energizing.

c) Control cable connections contain index grooves. Use care to locate

matching grooves before mating connectors.

SEL ® is a registered trademark of Schweitzer Engineering Laboratories, Inc. (SEL)

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A

PHASE ORIENTATION

BC

Figure 2. Typical Installation

DRAWING NO. REV

LBS-250111R1 0

25.8 KV SOLID DIELECTRIC LOAD BREAK SWITCH

SEL-751 SECTIONALIZER CONTROL

DATE

MAY-2018

NOTES

1. MOLDED DIELCTRIC BUSHINGS

2. ENCAPSULATED VOLTAGE AND CURRENT

SENSORS

CTR 1000:1 +/- 1% ACCURACY

RVD 3300:1 +/- 2% ACCURACY

3. SEL-751 SECTIONALIZER CONTROL

4. 24V DC BATTERY

5. 120V AC CONTROL VOLTAGE

6. STAINLESS STEAL TANK – ANSI GRAY

7. MANUAL OPERATING HANDLE

8. VISUAL POSITION INDICATOR

9. MECHANICAL LOCKING DEVICE

10. ALL-WEATHER CONTROL CABLE

11. GALVENIZED CENTER-MOUNT BRACKET WITH

LIFTING EYES

12. ARRESTER PROVISIONS

13. BIRD GUARDS INCLUDED

14. LUG OPTIONS – 2 HOLE, 4 HOLE, CLAMP

A B C

SOURCE

CT

1000:1

V VV

RVD

3300:1V VV

LOAD

A B C

SPECS

RATED VOLTAGE KV25.8

RATED CONTINUOUS CURRENT, RMS A630

BASIC IMPULSE LEVEL KV150

FREQUENCY HZ50/60

SHORT TIME CURRENT, RMS 1 SEC. KA12.5

SWITCH WEIGHT LBS300

SHIPPING WEIGHT LBS650

CBA

SOURCE

LOAD

SOURCE

LOAD

A

B

C

A

B

C

C AB

SOURCE

LOAD

PHASING