Circuit Breaker LTB D 72.

5 - 170 kV
FSA spring operating mechanisms

For single-pole operation

LTB D - proven design

LTB D circuit breakers with the ABB Auto- Main features and advantages
PufferTM interrupter and spring operating
mechanisms have been reliably serving utilities • Low energy, arc-assisted Auto-puffer™ interrupter
around the world since 1991. Over 20,000 units
have been delivered to over 120 countries with • High dielectric strength and electrical endurance from
an excellent record of performance. optimized contact system design (IEC class C2)

The LTB D is designed for system voltages 72.5 – 170 kV • Proven nitrile rubber double sealing systems
and rated for breaking current of 40 kA. LTB D is one
member of the extensive and proven ABB SF6 circuit • Available with porcelain (brown or grey) or silicone
breaker family, which covers the voltage range from 72.5 rubber composite insulators
up to 800 kV and for breaking capabilities up to 80 kA.
• Trip-free, cam disc, spring operating mechanisms
The LTB D for single pole operation has been optimized (IEC class M2)
using the well proven FSA 1 spring operating mechanism
in compliance with the major international standards • Vibration proof, multi-stage operating latches with low
including IEC and ANSI. operating power
Design
The three poles of the circuit breaker are mounted on a • High seismic withstand capability (0.5 g) due to opti-
pole beam, supported by a two column frame. Each pole mized support design
is equipped with its own spring operating mechanism
of trip-free design, containing both closing and tripping • Mechanically connected circuit breaker position and
springs. The operating mechanisms are mechanically spring charge status indicators
identical. Operational controls are centralized in the
centre mechanism and cabling between mechanisms • Full functional module based controls design provid-
is factory installed and tested prior to delivery. Minimum ing ease of specification and security of delivery and
adjustment of the circuit breaker is required during site performance
assembly.
• Factory installed and tested cabling. No site cabling
The circuit breaker poles are identical sealed, single installation required between operating mechanisms
pressure, SF6 units, including breaking unit and hollow
post insulators and mechanism housings. The poles are • Modular component design, allowing rigorous, staged
connected by factory installed SF6 gas piping connected and complete factory testing and minimum spare
to a central manifold block for site filling and SF6 density parts inventory
monitoring. ABB’s well proven double nitrile rubber static
and dynamic seal designs ensure a maximum SF6 leak • Optimized packing and delivery arrangement to en-
rate of less than 0.5% per year. sure transport safety and simple, rapid installation
Simply reliable, fully functional
• Integrated Central Control Cubicle, CCC
ABB’s more than 100 years experience in the delivery of
HV circuit breakers worldwide guarantees our customers
can easily specify what they require and be assured of
receiving their circuit breakers on time and to the high
quality expected and guaranteed by ABB. The LTB D
single-pole operated design can be specified by rated
voltage, insulator type, phase distance, control voltage
and pre-engineered flexible range of control functions.

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Installation in less than one day

The functionally modular design, delivered fully tested from ABB allows the complete circuit breaker to be installed
and ready for use within one day. Minimum adjustment of the circuit breaker is required during installation on site
commissioning.

1. Delivery

Case 1: Welded support frame

Case 2: Circuit breaker poles Case 3: Operating mechanisms, mounted on pole

beam with preterminated interphase cabling

2. Install support frames on foundation 3. Bolt pole beam to support frames

(30 minutes) (30 minutes)

Foundation Foundation

Note! Installation times are indicative only and subject to work by suitably trained personnel with appropriate tools. All
site works must be carried out in accordance with local laws, safety regulations and relevant ABB product information
manual delivered with the circuit breaker.

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Installation in less than one day

4. Install poles on pole beam 5. Install substation cabling and HV

(75 minutes) connections (180 minutes)

6. SF6 gas filling (45 minutes) 7. Site commissioning tests (60 minutes)

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Electrical controls — pre-engineered functional modules
for operational security
All interphase controls of the circuit breaker are completed in the ABB factory. No site cabling is required, ensuring
fast and error free installation. All main circuit functions have been developed into pre-engineered modules that
provide the user with simplicity of ordering and security of function. The standardized circuit and wiring design enables
a high degree of automated quality control in the production of the circuit breaker.
Cabling is terminated using positive clip lock, vibration proof plug connections. All internal cabling is indelibly marked
with unique cable numbers. Interphase cables have halogen free compound insulation, UV resistant sheaths and
overlapped copper tape screens. Separate gland plate provided for substation cable entry. Well spaced, vertically
mounted terminal blocks provided in central operating mechanism for connection of substation control and signalling
cables.

Circuits Auxiliary SF6 density Spring Anti- Control Local Trip / Close MCB Power
contacts monitor limit pump selector switch operation local switch outlet
Two level: switch relay Local / Remote selection earth fault
Refill/ / Disconnected Single-/ MCB
Blocking Three-pole (RCD)
operation
Close Standard Standard Standard Standard Standard Standard Standard
Trip 1 Standard Standard Standard Standard Standard
Trip 2 Standard Standard Standard Standard
Motor Standard Standard
Heater and
auxiliaries
70 W continuous Standard Optional
140 W thermostat
controlled
Signalling 7+7 1+1 1+1 1+1 1+1 Optional
Normally
- Rotary
closed
wiping
contacts.
Device action Rotary, Rotary,
Temperature Rotary
description padlockable spring return
compen-
- Double
sated.
break
MPa abs.

Standard Option
Control voltage 110 - 125 VDC 220 - 250 VDC
Motor voltage 110 - 125 VDC 220 - 250 VDC 220 VAC 120 VAC
Heater and auxiliary voltage 220 VAC 120 VAC

Additional options
Undervoltage relay
Pole discrepancy
Spring charge failure monitoring
Door switch activated internal lamp
Preparation for trip circuit supervision

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Technical data according to IEC

General
Circuit breaker type LTB 72.5 D1/B 145 D1/B 170 D1/B
Type of operation 1-pole operation
Number of poles 3
Porcelain (brown-standard / grey - option) mm/kV 25 or 31
Composite silicone rubber (option) mm/kV 25
Operating temperature º C -30 to +40 (Lower or higher on request)
Seismic withstand 0.2 - 0.5 g

Ratings and guaranteed performance in accordance with IEC 62271-100

Rated voltage kV 72.5 145 170
Rated insulation level
Lightning impulse withstand voltage
to earth kVpeak 325 650 750
across the open circuit-breaker kVpeak 325 650 750
Power frequency withstand voltage
to earth, dry kV 140 275 325
across the open circuit-breaker, dry kV 140 275 325
Rated frequency Hz 50/60
Rated normal current A 3150
Rated short-circuit breaking current kA 40
First-pole-to-clear factor 1.5
Rated short-circuit making current kApeak 100
Rated operating sequence O-0.3 s-CO-3 min-CO
Rated duration of short-circuit current (40 kA) s 3
Opening time ms 28-35
Break time ms ≤ 50
Closing time ms ≤ 70
Capacitive current switching Class C2
Mechanical endurance Class M2

Operating mechanism
Motor operated spring closing mechanism Type FSA1
Degree of protection IP55
Power required at rated supply voltage by
Closing coil W 500
Opening coil W 500
Motor W 740
Heating elements, continuously W 70
Heating elements, connected by thermostat W 140
Number of spare auxiliary contacts Normally open 7
Number of spare auxiliary contacts Normally closed 7

Masses and dimensions

Mass of breaker module excl. operating mechanism
kg 3 x 300 / 3 x 130
(porcelain / polymer insulators)
Operating mechanism kg 177 + 142 x 2

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Dimensions and shipping data LTB D

LTB D1/B Two-column stand,

Single-pole operation
Rated Voltage: 72.5 - 170 kV

Dimensions (mm)
Rated Rated
A B C D E F Height to lowest part of insulator **
Voltage Voltage
72.5 kV 4647 1164 670 3280 1750 4189 72.5-170 kV 2501* 2946 3529
145 kV 5197 1164 1220 3830 1750 4189 *) Standard
170 kV 5808 1475 1520 4130 1750 4189 **) Other dimensions can be provided

Available dimensions for phase distances

and heights to lowest part of insulator (mm) Dimensions between stands. Centre to centre (mm)

Rated Phase distance Stand distance

Phase distance 1500 1500
Voltage
72.5 kV 1500 1750* 2000 2500 1750 2000
145 kV - 1750* 2000 2500 2000 2530
170 kV - 1750* 2000 2500 2500 2530
*) Standard

267
E E

C
A
1 2

D Legend:
3 4
1. Central control cubicle

2501 2. SF6 density monitor

2140
2000

580 3. CB position indication

707

spring charge indication

1162 574
4. Manual spring charge
756 handle access

Shipping data (three packages per circuit breaker)

Type Circuit breaker poles Support structure Pole-beam with operating mechanism
Dimension Gross weight (kg) Dimension Gross weight Dimension Gross weight
(m) Porcelaine/Composite (m) (kg) (m) (kg)
LTB 72.5 D1/B 3.26 x 1.78 x 0.72 1130 / 710 2.17 x 0.90 x 0.53 370 4.41 x 1.11 x 2.25 1100

LTB 145 D1/B 3.26 x 1.78 x 0.72 1250 / 740 2.17 x 0.90 x 0.53 370 4.41 x 1.11 x 2.25 1100

LTB 170 D1/B 3.90 x 1.78 x 0.72 1500 / 840 2.17 x 0.90 x 0.53 370 4.41 x 1.11 x 2.25 1100

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 ©Copyright 2007 ABB, All right reserved. Publication 1HSM 9543 22-10en, Circuit Breaker LTB D 72.5 - 170 kV with spring operating mechanism FSA, Edition 1, 2007-08. Print: www.henningsons.se

ABB AB NOTE! ABB AB is working continuously to improve the

products. We therefore reserve the right to change designs,
High Voltage Products dimensions and data without prior notice.
SE-771 80 LUDVIKA, SWEDEN
Tel: +46 (0)240 78 20 00
Fax: +46 (0)240 78 36 50
E-mail: circuit.breakers@se.abb.com
Internet: http://www.abb.com