bts3012a technical manual-auxiliary system(v3.30).pdf

Chapter 1 Introduction to Auxiliary System 1-1..................................................1.1 Overview 1-1................................................................................................1.2 Introduction to Auxiliary System 1-1.............................................................

Chapter 2 Power Supply System 2-1....................................................................2.1 AC/DC Distribution Unit 2-1..........................................................................

2.1.1 Overview 2-1........................................................................................2.1.2 Introduction to AC/DC Distribution Unit 2-1..........................................2.1.3 AC Distribution Principle 2-3................................................................2.1.4 DC Distribution Principle 2-5................................................................

2.2 Transmission Power Supply 2-7...................................................................2.3 Storage Batteries 2-8....................................................................................

2.3.1 Built-in Storage Battery Box 2-8...........................................................2.3.2 Extended Storage Battery Cabinet 2-8................................................2.3.3 Transformer 2-9...................................................................................

2.4 Regulator 2-9................................................................................................Chapter 3 Environment Monitoring System 3-1..................................................

3.1 Overview 3-1................................................................................................3.2 TCU 3-2........................................................................................................

3.2.1 Overview 3-2........................................................................................3.2.2 Architecture and Principle 3-2..............................................................

Chapter 4 Temperature Adjustment System 4-1.................................................4.1 Overview 4-1................................................................................................4.2 Air Conditioner 4-1........................................................................................4.3 Heat Exchanger 4-1......................................................................................

Chapter 5 Transmission Mode 5-1.......................................................................5.1 E1 Transmission 5-1.....................................................................................5.2 SDH Transmission 5-3.................................................................................

Chapter 6 BTS Lightning Protection Grounding 6-1..........................................6.1 Overview 6-1................................................................................................6.2 BTS Lightning Protection Principle 6-1.........................................................

6.2.1 Principle and Characteristics 6-1.........................................................6.2.2 AC Lightning Protection 6-2.................................................................6.2.3 BTS Trunk Cable Lightning Protection 6-2...........................................6.2.4 Antenna and Feeder Subsystem Lighting Protection 6-3.....................

6.3 BTS System Grounding 6-4..........................................................................6.3.1 Cabinet Internal Grounding 6-4............................................................6.3.2 Cabinet External Grounding 6-4...........................................................

6.3.3 AC Lightning Arrester Grounding 6-4...................................................6.3.4 Transmission Equipment Grounding 6-4..............................................6.3.5 Metal Sheath Grounding for Overhead E1 and HDSL Cables 6-5.......6.3.6 BTS Surge Protector Grounding 6-5....................................................

HUAWEI

M900/M1800 BTS3012A Base Transceiver Station Technical Manual - Auxiliary System

V300R003

M900/M1800 BTS3012A Base Transceiver Station

Technical Manual

Volume Auxiliary System

Manual Version T2-030217-20041110-C-3.30

Product Version V300R003

BOM 31026317

Huawei Technologies Co., Ltd. provides customers with comprehensive technical support and service. Please feel free to contact our local office, customer care center or company headquarters.

Huawei Technologies Co., Ltd.

Address: Administration Building, Huawei Technologies Co., Ltd.,

Bantian, Longgang District, Shenzhen, P. R. China

Postal Code: 518129

Website: http://www.huawei.com

Email: [email protected]

2004 Huawei Technologies Co., Ltd.

All Rights Reserved

No part of this manual may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

Trademarks

, HUAWEI, C&C08, EAST8000, HONET, , ViewPoint, INtess, ETS, DMC,

TELLIN, InfoLink, Netkey, Quidway, SYNLOCK, Radium, M900/M1800, TELESIGHT, Quidview, Musa, Airbridge, Tellwin, Inmedia, VRP, DOPRA, iTELLIN, HUAWEI OptiX, C&C08 iNET, NETENGINE, OptiX, iSite, U-SYS, iMUSE, OpenEye, Lansway, SmartAX, infoX, TopEng are trademarks of Huawei Technologies Co., Ltd.

All other trademarks mentioned in this manual are the property of their respective holders.

Notice

The information in this manual is subject to change without notice. Every effort has been made in the preparation of this manual to ensure accuracy of the contents, but all statements, information, and recommendations in this manual do not constitute the warranty of any kind, express or implied.

About This Manual

Release Notes

The product version corresponds to the manual is M900/M1800 BTS3012A Base Transceiver Station V300R003.

Organization

The manual describes system description of M900/M1800 BTS3012A.

There are six chapters and three appendixes in the manual.

Chapter 1 Introduction to Auxiliary System introduces all the sub-system of the auxiliary system.

Chapter 2 Power Supply System introduces the power supply system of BTS3012A, including AC/DC distribution unit, transmission power supply, storage batteries and regulator power supply.

Chapter 3 Environment Monitoring System introduces the environment monitoring system of BTS3012A, including sensors, TCU and PMU.

Chapter 4 Temperature Adjustment System introduces the temperature adjustment system of BTS3012A, including air-conditioner and heat exchanger.

Chapter 5 Transmission Mode introduces the transmission modes of BTS3012A, including E1, SDH transmission.

Chapter 6 BTS Lightning Protection Grounding introduces the lightning protection grounding of BTS3012A, including AC lightning protection, trunk cable lightning protection, antenna and feeder subsystem lightning protection and the BTS system grounding.

Intended Audience

The manual is intended for the following readers:

z Technical marketing specialists z Installation engineers and technicians z Operation and maintenance personnel

Conventions

This manual uses the following conventions:

I. General conventions

Convention Description

Arial Normal paragraphs are in Arial.

Arial Narrow Warnings, Cautions, Notes and Tips are in Arial Narrow.

Boldface Headings are in Boldface.

II. Symbols

Eye-catching symbols are also used in the manual to highlight the points worthy of special attention during the operation. They are defined as follows:

Caution, Warning, Danger: Means reader be extremely careful during the

operation.

Note, Comment, Tip, Knowhow, Thought: Means a complementary description.

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Table of Contents

i

Table of Contents

Chapter 1 Introduction to Auxiliary System ............................................................................... 1-1 1.1 Overview ............................................................................................................................ 1-1 1.2 Introduction to Auxiliary System ........................................................................................ 1-1

Chapter 2 Power Supply System ................................................................................................. 2-1 2.1 AC/DC Distribution Unit ..................................................................................................... 2-1

2.1.1 Overview ................................................................................................................. 2-1 2.1.2 Introduction to AC/DC Distribution Unit................................................................... 2-1 2.1.3 AC Distribution Principle ......................................................................................... 2-3 2.1.4 DC Distribution Principle ......................................................................................... 2-5

2.2 Transmission Power Supply .............................................................................................. 2-7 2.3 Storage Batteries ............................................................................................................... 2-8

2.3.1 Built-in Storage Battery Box .................................................................................... 2-8 2.3.2 Extended Storage Battery Cabinet.......................................................................... 2-8 2.3.3 Transformer............................................................................................................. 2-9

2.4 Regulator ........................................................................................................................... 2-9

Chapter 3 Environment Monitoring System ............................................................................... 3-1 3.1 Overview ............................................................................................................................ 3-1 3.2 TCU.................................................................................................................................... 3-2

3.2.1 Overview ................................................................................................................. 3-2 3.2.2 Architecture and Principle ....................................................................................... 3-2

Chapter 4 Temperature Adjustment System .............................................................................. 4-1 4.1 Overview ............................................................................................................................ 4-1 4.2 Air Conditioner ................................................................................................................... 4-1 4.3 Heat Exchanger ................................................................................................................. 4-1

Chapter 5 Transmission Mode ..................................................................................................... 5-1 5.1 E1 Transmission ................................................................................................................ 5-1 5.2 SDH Transmission............................................................................................................. 5-3

Chapter 6 BTS Lightning Protection Grounding........................................................................ 6-1 6.1 Overview ............................................................................................................................ 6-1 6.2 BTS Lightning Protection Principle .................................................................................... 6-1

6.2.1 Principle and Characteristics................................................................................... 6-1 6.2.2 AC Lightning Protection .......................................................................................... 6-2 6.2.3 BTS Trunk Cable Lightning Protection.................................................................... 6-2 6.2.4 Antenna and Feeder Subsystem Lighting Protection.............................................. 6-3

6.3 BTS System Grounding ..................................................................................................... 6-4 6.3.1 Cabinet Internal Grounding ..................................................................................... 6-4

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Table of Contents

ii

6.3.2 Cabinet External Grounding.................................................................................... 6-4 6.3.3 AC Lightning Arrester Grounding............................................................................ 6-4 6.3.4 Transmission Equipment Grounding....................................................................... 6-4 6.3.5 Metal Sheath Grounding for Overhead E1 and HDSL Cables................................ 6-5 6.3.6 BTS Surge Protector Grounding ............................................................................. 6-5

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Chapter 1 Introduction to Auxiliary System

1-1

Chapter 1 Introduction to Auxiliary System

1.1 Overview

Auxiliary system refers to the equipment and devices in various working systems that assist the normal operation of BTS. The components of BTS3012A auxiliary system includes power supply system, environment monitoring system and temperature adjustment system, as illustrated in Figure 1-1.

Abis

Um

MS BSCMain cabinetEnvironment monitoring system

Power distribution system

Temperature adjustment system

Auxiliary cabinet

BTS3012A

Figure 1-1 BTS3012A auxiliary system composition

In addition, the transmission equipment principle and lightning protection will also be introduced.

1.2 Introduction to Auxiliary System

I. Power supply system

Power supply system provides power for the stable working of BTS main and auxiliary equipment.

BTS3012A power supply system consists of four parts, AC/DC distribution unit, transmission power supply Unit (TSU), transformer and storage batteries.

II. Environemtn monitoring system

Environment monitoring system accomplishes the monitoring of the environment variables in the cabinet and the alarm processing functions to keep the cabinet in a suitable temperature and humidity range and ensure the safe and reliable operation of the equipment.

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Chapter 1 Introduction to Auxiliary System

1-2

TCU and sensors are the major components of environment monitoring system.

III. Temperature adjustment system

Temperature adjustment system can adjust the internal temperature of the cabinet to keep the main equipment working reliably in a mild environment. Air-conditioner / Heat exchanger is the major component of temperature adjustment system.

IV. BTS transmission equipment

Many types of small transmission equipment can be embedded in BTS3012A to support various transmission modes, including E1 (75 /120), SDH and microwave, etc.

V. BTS lightning protection grounding

As an outdoor macrocell BTS, BTS3012A is required to have higher lightning protection performance, therefore, all ports where lightning might be led, including AC power port, E1 port and antenna and feeder port, have been designed with comprehensive lightning protection technique.

Note: Some of the above auxiliary equipment is optional. If no special note is given in the following chapters of this section, the equipment mentioned is mandatory.

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Chapter 2 Power Supply System

2-1

Chapter 2 Power Supply System

The power supply system of BTS3012A consists of AC/DC distribution unit, Transmission power Supply Unit (TSU), transformer and storage batteries. The regulator will also be introduced in this chapter.

2.1 AC/DC Distribution Unit

2.1.1 Overview

Functionally the AC/DC distribution unit accomplishes two functions: AC distribution and DC distribution. The DC distribution includes that for auxiliary equipment and that for main equipment. AC distribution is achieved by the AC distribution frame in the auxiliary equipment cabinet, DC distribution for auxiliary equipment by the DC distribution frame in the auxiliary equipment cabinet and DC distribution for the main equipment by the DC distribution frame in the main equipment cabinet. The AC/DC conversion is performed by the PSU. Figure 2-1 shows the AC/DC distribution principle.

DC distribution frame in the main equipment cabinet

Main equipment cabinet

DC distribution

AC distribution frame

PSU

220V AC input

AC distribution

+24VDC+24VDC

Transformer110V AC input

220VAC

Auxiliary equipment cabinet

Auxialiary equipment cabinet

+24VDC

Storage batteries

+24VDC

DC distribution frame in the auxiliary equipment cabinet

Figure 2-1 AC/DC distribution principle

2.1.2 Introduction to AC/DC Distribution Unit

The AC/DC distribution unit in the auxiliary system is composed of one AC switch box, one DC switch box and one transmission power supply unit (TSU), as shown in Figure 2-2 .


2-2

REGULATOR BTS

(1) AC switch box (2) DC switch box (3) TSU

Figure 2-2 AC/DC distribution box

Table 2-1 describes the switches and sockets on the AC switch box. There are two 220V sockets on the AC switch box for connecting testing devices for equipment maintenance.

Table 2-1 Switches on the AC switch box

Switch Function Current limiting specification

REGULATOR Power supply switch for current stabilizer 32A

BTS Power supply switch for main equipment of the BTS3012A 32A

TCU AC supply switch for TCU 10A

AUX Power supply switch for the sockets 10A

Table 2-2 describes the switches/sockets on the DC switch box.

Table 2-2 Switches/sockets on the DC switch box

Switch/socket Function Current limiting specification

SPARE Spare switches 20A

FAN1 Fan switch for auxiliary equipment 5A

LAMP Lamp switch 5A

TSU Power switch for TSU 20A


2-3

Switch/socket Function Current limiting specification

HX Switch for the air conditioner or heat exchanger 20A

BAT Switch for storage batteries 5A

2.1.3 AC Distribution Principle

The AC distribution of BTS3012A supports multiple AC distribution modes: 220V AC three-phase distribution, 220V AC single-phase distribution, 110V AC three-phase distribution and 110V AC single-phase distribution.

I. 220V AC three-phase distribution

The three-phase 220V AC travels through the arrester and the EMI filter, then is accessed to the AC distribution unit to be distributed to the regulator, PSU and the socket (standby). The input end of each phase is protected by a Miniature Circuit Breaker (MCB). Refer to Figure 2-3 for the distribution principle.

Arrester

220V AC input

MCB EMI filter

A

N

B

N

C

N

Contactor

32A

5A

Regulator Air conditioner/heat exchanger

32A

PSUInput to the DC distributin frame

TCU

5A

AC distribution unit

A,N

B,N

+24V DCN

ABC

Socket 1L,N

Socket 2

Figure 2-3 Principle of AC distribution unit (220V AC three-phase distribution mode)

In Figure 2-3, the MCB, the arrester and the EMI filter are all installed in the lighting protection filter box in the auxiliary equipment cabinet. The panel of the lightning protection filter box is shown in Figure 2-4. The MCB on the panel is the power switch for the cabinet. The L1, L2 and L3 are the lightning protection indicators of the arrester for the three-phase AC. When one of the three indicators is red, it means the lightning protection of the arrester fails.


2-4

Off

On

Danger High Voltage

Power Outage, Maintenance

Red=FaultGreen=Normal

L1

L2

L3

Figure 2-4 Panel of the lightning protection filter box

II. 220V AC single-phase distribution

When the 220V AC single-phase distribution is adopted, a connector post will be installed before the MCB in the BTS3012A to convert the single-phase distribution mode to the three-phase distribution mode. Through the connector post and the MCB, three-phase AC is output. The power distribution principle in the cabinet is the same as that of the 220V AC. Refer to Figure 2-5 for the distribution principle.

Arrester

220V AC input

MCB

LEMI

filter

L

N

L

N

LN

Contactor

Socket 1

32A

5A

Regulator

32A

5A


L,N

L,N

L,N

Air conditioner/heat exchanger

PSUInput to DC distributin frame

TCU

+24V DC

N

Socket 2

Figure 2-5 Principle of AC distribution unit (220V AC single-phase distribution mode)

III. 110V AC three-phase distribution

The three-phase 110V AC is first converted by the transformer before it is led into the AC distribution unit to provide power to corresponding devices. When two 4kVA transformers are used, two phases of AC are provided to the PSU and the regulator after being converted by the transformer and the third phase of AC is provided to the socket without being converted by the transformer. The principle of the AC distribution is illustrated in Figure 2-6. When only one 7kVA transformer is used, there is only one phase of AC will be converted by the transformer. The principle of AC distribution under this case is similar to that in Figure 2-6.


2-5

Arrester

110V AC input

MCB

A

N

EMI filter

Transformer

Transformer

BC

A

N

B

N

C

N

Contactor

Socket 1

32A

5A


32A

PSUInput to DC distribution frame

TCU

5A


A,N

B,N

C,N

+24VDC

Socket 2

Figure 2-6 Principle of AC distribution (110V AC three-phase distribution mode)

IV. 110V AC single-phase distribution

When 110V AC single-phase distribution is adopted, a connector post will be installed before the MCB in the BTS3012A to convert the single-phase distribution mode to the three-phase distribution mode. Through the connector post and the MCB, three-phase AC is output. The power distribution principle in the cabinet and the selection of transformer model are the same as that of the 110V AC three-phase distribution mode. Refer to Figure 2-7 for the principle of the AC distribution.

Arrester

110V AC input

MCBL

N

EMI filter

Transformer

Transformer

L

N

L

N

L

N

Contacotr

Socket 1

32A

5A


32A

PSUInput to DC distribution frame

TCU

5A


L,N

L,N

L,N

+24VDC

Socket 2

Figure 2-7 Principle of AC distribution unit (110V AC single-phase distribution mode)

2.1.4 DC Distribution Principle

The DC distribution unit of BTS3012A is responsible for the distribution of +24V DC output from the PSU. The AC/DC conversion is accomplished by the PSU. See Figure 2-8 for the principle of AC/DC conversion. The 220V AC is output from the AC distribution unit to the 220V AC input bus bar on the backplane of the public resource frame. Then it is converted to multiple channels of +24V DC by the PSU (AC/DC) module on the backplane and is output to the output bus bar.


2-6

AC input lightning protection power distribution unit A1441Z

PSU PMUPSU PSU

220 V AC input

+24 V DC output

Input bus bar

Output bus bar

DC ditribution copper bar

Figure 2-8 Principe of AC/DC conversion

DC distribution copper bar allocates the +24V current output from PSU to two units, power distribution unit for auxiliary equipment and that for main equipment.

I. DC distribution for auxiliary equipment

The DC distribution for auxiliary equipment outputs 9 channels of DC to TMU, transmission equipment, storage batteries, fan frame in auxiliary equipment cabinet, one lamp, one redundant terminal, heat exchanger, TCU and carrier frame. See Figure 2-9 for the principle of DC distribution for auxiliary equipment.

TMU

Contactor

FAN1

LAMP(1)

Spare

Heat exchager

5A

20A

Transmission equipment

150A 120A

120A

5A

20A

5A

+24V DC input

+24V DC

TSU

DC fuse protector Storage battery

20A

20A Transmission equipment



Contactor

5A

5A

DC distribution for the auxiliary equipment cabinet

Input to the carrier frame

TCU

Figure 2-9 DC distribution for auxiliary equipment


2-7

II. DC distribution principle for main equipment

The DC distribution unit outputs 13 channels of DC to 6 TRXs, 6 CDUs and 1 fan in the main equipment cabinet. See Figure 2-10 for the principle of DC distribution for main equipment.

2TRX

2TRX

2TRX

2TRX

2TRX

2TRX

CDU

CDU

CDU

CDU

CDU

CDU

Fan 2

20A

20A

20A

20A

20A

20A

20A

20A

20A

20A

20A

20A

20A

DTX2(+24VDC)

DC distribution for main equipment

Figure 2-10 DC distribution for main equipment

2.2 Transmission Power Supply

BTS3012A provides three types of power supply for its built-in transmission equipment, +24V DC, 220V AC and -48V DC.

The Transmission power Supply Unit (TSU) provides -48V DC to the transmission equipment. It is a DC/AC converter that converts +24V DC output from the PSU to -48V DC to be used by the built-in transmission equipment. The TSU works under 1+! backup mode. Normally the two TSUs output equalized current. When one TSU gets faulty, another TSU will supply power to the transmission equipment and reports alarms.

Note: The TSU is optional.


2-8

2.3 Storage Batteries z When the mains supply is cut off, BTS3012A can sustain its service by the power

supply from storage batteries. Built-in storage battery box and extended storage battery cabinet are provided for BTS3012A.

Note: Storage batteries are optional.

2.3.1 Built-in Storage Battery Box

Built-in storage battery box is installed in the auxiliary equipment cabinet and accommodates two 100Ah storage batteries. It can sustain the service of three BCCH carriers for above30 minutes when the mains supply is cut off.

Two types of batteries can be selected for the built-in storage battery box: common storage battery and low-temperature storage battery.

Technical indices of the common storage battery are listed below:

z Rated voltage: 12V DC z Rated capacity: 100Ah z Working temperature:-15C ~ +45C z Floating voltage: 13.38V (+25C) z Max. charging current: 25A

Technical indices for low temperature storage batteries are listed in the following:

z Rated voltage: 12V DC z Rated capacity: 100Ah z Working temperature:-40C ~ +50C z Floating voltage: 13.38V (+25C) z Max. charging current: 25A

2.3.2 Extended Storage Battery Cabinet

Extended storage battery cabinet has more powerful power backup capacity. It can accommodate twelve 650Ah storage batteries with rated voltage as 2V to improve the power supply duration after the mains supply is cut off. Under full configuration of the BTS3012A, the power backup duration is more than 4 hours.

Technical indices of the extended storage battery cabinet are listed as follows:

z Rated voltage: 24V DC


2-9

z Rated capacity: 650Ah z Working temperature: -20C ~ +50C z Floating voltage: 26.8V (+25C) z Max. charging current: 130A

2.3.3 Transformer

Note: The transformer is optional.

The transformer is used in the cabinets with 110V AC for the conversion between 110V AC and 220V AC.

The transformer has two rated powers: 4kVA and 7kVA. Two transformers with rated power as 4kVA are required in a 110 V AC cabinet with an air conditioner, or in a 110V AC cabinet with a heat exchanger but without the extended storage battery cabinet. While one 7kVA transformer is required in a 110V AC cabinet with a heat exchanger and an extended storage battery cabinet.

2.4 Regulator

The working voltage input range of the BTS3012A with an air conditioner or heat exchanger is 220V AC 20%. A regulator is recommended for areas with unsteady voltage. The working voltage input range of the BTS3012A with a regulator is 150V AC ~ 300V AC. After the voltage regulating of the regulator, the BTS3012A can output the voltage of 220V AC!10% to the air-conditioner or heat exchanger. The working temperature of the regulator is -40C ~ +55C.

Note: The regulator is optional.

Indicators on the regulator are described in Table 2-3.

Table 2-3 Description of indicators on the regulator in BTS3012A

Indicator name Color Status Indication

ON There is 220V AC input NORMAL (power indicator) Green

OFF There is no 220V AC input


2-10

Indicator name Color Status Indication

ON Protection or fault occurs. FAULT (fault indicator) Red

OFF Normal

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Chapter 3 Environment Monitoring System

3-1

Chapter 3 Environment Monitoring System

3.1 Overview

As the core control system of BTS3012A, environment monitoring system is responsible for the monitoring and control of the environment in BTS3012A. It is composed of three parts, sensors, TCU (Temperature Control Unit) and PMU, functioning as the following: 1) Sensors are embedded in the BTS3012A cabinet and the extended storage

battery cabinet. Sensors in the BTS3012A cabinet include temperature sensor, door control sensor, water sensor and smog sensor, and sensors in the extended storage battery cabinet include temperature sensor and door control sensor. Environment variables are collected by PMU.

2) TCU provides temperature protection to the main equipment. When the temperature is too high or too low, TCU will cut off the 220V AC input and the +24V DC output from the storage batteries and power off some of the boards to prevent the main equipment from damage.

3) TMU collects the alarm input toggle value of the transmission power supply, AC lightning protection unit, regulator and the air-conditioner through TCB (Temperature Control Backplane).

PMU

Sensor

TCU

Storage battery

TRX/CDU

Voltage Stabilizer

Air conditioner/ heat exchanger

TMU

Monitoring Subsystem

AC lightning protection board

Alarm signals

Control signals

Control signals

Temprature TestAccess testWater testSmoke test

Figure 3-1 BTS3012A environment monitoring system


3-2

The detailed function description of PMU and TMU is given in M900/M1800 BTS3012A Base Transceiver Station Technical Manual System Principle, so they will not be repeated here.

3.2 TCU

3.2.1 Overview

TCU real-time monitors the temperature in the cabinet. By controlling the power distribution of the cabinet, it can prevent the damage of over-high or over-low temperature to the equipment and components. In this way, the normal working of the main equipment can be assured.

TCU is located in the main equipment frame, as shown in Figure 3-2.

TMU

TCU

PSU

PSU

PSU

PSU

PSU

PSU

ABB

PMU

Figure 3-2 TCU in the frame

3.2.2 Architecture and Principle

TCU controls the 220V AC input from the external power supply, the +24V DC output of the storage batteries (excluding the power distribution of the air-conditioner) and the power-on/off commands for some boards according to the temperature of the cabinet. For the control logic of TCU, refer to Figure 3-3.

TCU

TRX/CDU

Storage battery

220V AC

control signals

Figure 3-3 TCU control logic


3-3

TCU takes different measures to protect the main equipment at different temperature control point.

For example, when the cabinet is in the initial temperature, -20C, the main equipment will be in protection status, only the air conditioner/heat exchanger will be working, some non-BCCH carrier power amplifier will be closed (the specific number of power amplifiers to be closed can be configured through BSC data configuration) and no power supply will be input for the PSU.

When the temperature control device is started and the temperature goes higher until -5C, the main equipment will exit the protection status, the PSU will be powered on and some non-BCCH carrier power amplifiers that have been closed will be re-started.

When the temperature goes up until 60C, the main equipment will enter protection status again and the system power supply will be cut off, including PSU and storage batteries.

Similarly when the temperature goes down until 50C, the main equipment will re-exit the protection status. And when the temperature continues going down until -15C, the main equipment will enter the protection status again.

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Chapter 4 Temperature Adjustment System

4-1

Chapter 4 Temperature Adjustment System

4.1 Overview

The heat dissipation and heating under low temperature of outdoor BTS3012A are accomplished by temperature adjustment system. The temperature adjustment system has high reliability performance and reports alarms when faults occur. The temperature adjustment of BTS3012A is accomplished by the air-conditioner or the heat exchanger.

4.2 Air Conditioner

BTS3012A is a complete outdoor BTS with enclosed cabinet architecture. When the cabinet works in high temperature, the internal temperature of the cabinet will go up quickly so that the cabinet even cannot work normally, because the large amount of heat generated by the cabinet itself cannot be dissipated due to the enclosed architecture.

To reduce the internal temperature of the cabinet, the air-conditioner is installed in the front door of the cabinet to dissipate heat. The air-conditioner will form a temperature close loop to monitor and control the cabinet internal temperature. When the air-conditioner detects low temperature in the cabinet, it will start its internal heating boards and the inner circling fans to provide heating to the cabinet. When high temperature is detected, the air-conditioner will start cooling function to keep the working temperature in the cabinet within normal working range. In this way, the cabinet can work reliably in both high and low temperature environment.

The technical indices of the air-conditioner are listed in the following: z Rated voltage: 220V AC!20% z Rated frequency: 50/60Hz!3Hz z Heating power: 2600W z Refrigerating power: 1600W z Working temperature: -55C ~ +55C

4.3 Heat Exchanger

Heat exchanger is the other option to control the internal temperature. The heat exchanger installed in the front door of the BTS3012A cabinet is closed loop and can provide heat dissipation capacity when the maximum internal temperature can be

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Chapter 4 Temperature Adjustment System

4-2

greater than the maximum external temperature. It incorporates a simple design with a dry contact closure each for high temperature alarm and low temperature alarm. Compared to air conditioners, heat exchangers typically use fewer, higher reliability components, and have a less complicated design, all at a lower cost.

The technical indices of the heat exchanger are listed in the following: z Rated voltage: 220V AC!20% z Rated frequency: 50Hz!3Hz z Heat exchanging power: 400W z Heating power: 2600W z Working temperature: -55C ~ +45C (for 220V AC cabinet), -5C ~ +45C

(for 110V AC cabinet)

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Chapter 5 Transmission Mode

5-1

Chapter 5 Transmission Mode

BTS3012A supports multiple embedded transmission modes as described in the following.

z Reserve a space dimensioned as 222mm (height) % 400mm (width) % 310mm (depth).

z Provide four channels of 48V power supply. z Reserve cable outlets for embedded microwave and SDH.

In the following, the E1 transmission and SDH transmission networking modes for BTS3012A are covered.

5.1 E1 Transmission

BTS3012A E1 networking supports star, tree and chain connection modes according to the actual deployment of sites.

I. Star connection

Star connection can be applied to common office deployment. Each site can be connected to its BSC directly via E1 links. Therefore, star connection mode enjoys simple networking, easy and convenient maintenance, engineering and capacity expansion. Under star connection mode, signals travel less and the line reliability is high. But it requires greatest amount of transmission links among all the connection modes. Therefore, star connection is usually applied to densely populated cities.

The star connection of BTS3012A is illustrated in Figure 5-1, where each single line represents one channel of E1 link.

BSC

BTS3012A

BTS3012A

BTS3012A

Figure 5-1 BTS3012A E1 star connection


5-2

II. Tree connection

Under tree connection mode, the networking structure is rather complicated, signals travel longer and the line reliability is low, so the engineering and maintenance complexity is high, and re-constructing of the whole network have to be done for capacity expansion. But it requires less transmission links than star connection. Therefore, tree connection is usually applied to large areas with low population density.

Note that the levels of site signals traveling from BSC is limited, i.e., usually the series connection of sites cannot exceed 5, or we can say, the depth of the tree cannot exceed 5, because the BTS clock generally takes the phase lock of its upper network and each phase lock will bring along the degradation of clock quality.

The tree connection of BTS3012A is illustrated in Figure 5-2, where, each single line represents one channel of E1.

BSC BTS3012A

BTS3012A

BTS3012A

Figure 5-2 BTS3012A E1 tree connection

III. Chain connection

Under chain connection, signals travel longer and the line reliability is poor. Therefore, chain connection can be applied to strip-shaped areas with low population density, such as the area along railways and subways. In such areas, chain connection can better meet users' requirement and greatly reduce the amount of transmission equipment required. Similar to tree connection, the number of node series connected under chain connection cannot exceed 5.

In actual office deployment, usually combined connection is adopted to provide qualified communication service as well as save transmission equipment investment.

BTS3012A chain connection is illustrated in Figure 5-3, where each single line represents one or multiple channels of E1.


5-3

BSC BTS3012A BTS3012A

Figure 5-3 BTS3012A E1 chain connection

5.2 SDH Transmission

If SDH transmission equipment is installed, BTS3012A can support SDH transmission.

Whether to adopt chain connection or ring connection for SDH networking depends on the actual distribution of network routes. Usually ring connection is adopted as long as there is appropriate route distribution, because it has high self-healing capability. While for the areas along railways and subways, usually chain connection is adopted.

I. Ring connection

Ring connection has high self-healing capability, i.e., when an optical fiber gets damaged, ring connection network can heal itself into a chain connection network and the service will not be impacted. Ring connection for SDH networking is illustrated in Figure 5-4, where each single line represents one or multiple channels of E1 and each pair of lines represent one pair of optical fibers.

BSC BTS3012A BTS3012AOptical transceiver

Figure 5-4 BTS3012A SDH ring connection

II. Chain connection

SDH chain connection is illustrated in Figure 5-5, where each single line represents one channel of E1 and each pair of lines represent one pair of optical fibers.

BTS3012A BTS3012ABSC Optical transceiver

Figure 5-5 BTS3012A SDH chain connection

Technical Manual Auxiliary System M900/M1800 BTS3012A Base Transceiver Station Chapter 6 BTS Lightning Protection Grounding

6-1

Chapter 6 BTS Lightning Protection Grounding

6.1 Overview

Lightning protection system for communication equipment includes external lightning protection system and internal lightning protection system. The external lightning protection system is to protect the equipment against direct lightning stroke, including lightning receiver, lightning down-leading cable and grounding device. The internal lightning protection system is to protect the equipment against indirect stroke, such as thunder bolt induction, reverse lightning stroke, lightning wave intrusion and other lightning strokes that might cause danger to human beings and the equipment.

The purpose of equipment grounding is to provide the equipment with the capability of protecting against external electromagnetism interference and to ensure the safety of human beings and the equipment. The key of lightning protection is grounding, because a fine grounding can provide the equipment a low-resistance lightning electricity discharging channel.

6.2 BTS Lightning Protection Principle

6.2.1 Principle and Characteristics

As an outdoor BTS, BTS3012A adopts multiple internal and external lightning protection measures.

I. External lightning protection measures

BTS3012A adopts the equalized electric potential combining/grounding technology specified by IEC and ITU-T to ensure that no grounding electric potential difference will be generated during lightning striking and no damage will be done to the equipment due to the grounding electric potential difference.

II. Internal lightning protection measures

Measures of internal lightning protection include:

z AC lightning arrester is installed at the AC input port to prevent the AC from direct lightning stroke or inductive lightning. The lightning protection index of the AC input port is 40kA.


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z E1 lightning protection board is installed at the E1 port of BTS3012A to perform comprehensive protection to E1 signal ports. The lightning protection index of E1 port is 5kA.

z Antenna and feeder lightning arrester is installed at the feeder inlet to protect the steel tower against the striking current coupled into the feeder when the steel tower gets lightning stoke.

z The equalized electric potential connection and insulation design in the cabinet can prevent the cabinet from the damage of lightning stroke to a larger extent.

6.2.2 AC Lightning Protection

The overall power for BTS3012A is large, so AC lightning arrester is used at the AC input port as the first level of lighting protection measures. This parallel lightning protection can effectively prevent the BTS3012A from the damage of lightning stroke. It has the following features:

z Adopts symmetric compound circuits, applicable for the power supply environment with poor electric network quality.

z Adopts temperature-controlled circuit breaking technology with embedded over-current protection circuits to prevent the cabinet from the danger of fire..

z Common mode and differential mode full protection. z Adopts dual-color luminotrons to indicate the working states of the cabinet.

6.2.3 BTS Trunk Cable Lightning Protection

BTS3012A supports multiple transmission modes, E1 (75coaxial cables and 120 twisted pairs), SDH and microwave transmission. E1 port is liable for lightning induction; therefore, external lightning protection measures for E1 ports will be introduced in the following.

Lightning protection board is added at the trunk cable inlet for the lightning protection at E1 port of BTS3012A. An E1 lightning protection board is installed in the auxiliary equipment cabinet of BTS3012A, on which 16 E1 connectors, 2 DB37 connectors are equipped. Refer to Figure 6-1 for the illustration of E1 lightning protection board.


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RX0

TX0

RX1

TX1

RX2

TX2

RX3

TX3

IN

OUT

Figure 6-1 E1 lightning protection board

All E1 cables achieve the lightning protection through the E1 lightning protection board. The circuits on the board can prevent the lightning current going into the cabinet through E1 cables when the cabinet gets lightning stroke, and the circuits can also discharge most of the current through the electricity discharge tube when large current strikes the cabinet.

6.2.4 Antenna and Feeder Subsystem Lighting Protection

Antenna and feeder lightning protection is to protect the equipment against indirect lightning stroke, that is,, inductive lightning, which refers to the large current incurred to the feeder at the moment of lightning strike. Inductive lightning is liable to exert damage to the equipment.

BTS3012A adopts the following measures to protect the equipment against inductive lightning.

z Lightning rod for the antenna. The antenna is within the 45protection range of the lightning rod.

z Three GND points for the feeder. The feeder is grounded reliably at the steel tower top, steel tower bottom and the external side of the cabinet. When the height of the steel tower is greater than or equal to 60m, another GND point at the middle of the steel tower will be added for the metal sheath of the coaxial feeders.

z Antenna and feeder lightning arrester in the cabinet to prevent the lightning from being induced into the cabinet.

z The BTS steel tower and BTS equipment share one grounding network.


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6.3 BTS System Grounding

6.3.1 Cabinet Internal Grounding

The following measures are adopted for cabinet internal grounding:

z Grounding terminals are installed at the cable outlet port, the bottom and the door of the cabinet.

z Bus bar is installed to the main equipment cabinet, with public grounding cables. And the equipment is connected to the ground of the cabinet through the grounding cables.

z BTS3012A metal components have high electric conductivity and there is no insulation paint on the connection points of metal components.

z Cabinet frames, power distribution unit and PSU are all equipped with metal shells, which are reliably connected to the metal mechanical parts in the cabinet.

6.3.2 Cabinet External Grounding

Two measures shall be used for cabinet external grounding:

z The PGND of the BTS3012A shall be connected to the nearest PGND copper bar provided by the office party.

z If cabling rack is used for installation, the two ends of the cabling rack shall be led to the ground through separate grounding cables to release the excess electric charge caused by the lightning strike on the antenna & feeder and the electric induction.

6.3.3 AC Lightning Arrester Grounding

Use the following two measures for AC lightning arrester grounding:

z Install grounding device near AC lighting arrester and connect the grounding cables of the AC lightning arrester directly to the GND of the grounding device. Adopt dual-color (yellow and green) plastic insulation copper-core conducting cables with cross section area no less than 25mm2 and cable length less than 10cm.

z The grounding device of the AC lightning arrester is well connected to the mechanical parts of the cabinet, and their contact resistance is less than 50 m.

6.3.4 Transmission Equipment Grounding

z Grounding bar is installed near the transmission equipment. The GND cables from the transmission equipment are directly connected to the grounding bar. The dual-color (yellow and green) plastic insulation copper-core conducting


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cables with cross section area less than 25mm2 and cable length less than 20cm are used for the grounding cables.

z The grounding bar of the transmission equipment is well connected to the mechanical parts of the cabinet, and their contact resistance is less than 50m.

6.3.5 Metal Sheath Grounding for Overhead E1 and HDSL Cables

z Metal sheath grounding clamp for dedicated E1 overhead cables can be used for transmission lightning protection equipment.

6.3.6 BTS Surge Protector Grounding

z The grounding cables of the antenna and feeder lightning arrester is connected to the nearest grounding bar, which is connected to the grounding of the cabinet.

z The grounding cables of E1 lightning arrester are grounded through the mechanical parts of the cabinet, and they are less than 20cm.

ContentsCoverAbout This Manual Chapter 1 Introduction to Auxiliary System1.1 Overview1.2 Introduction to Auxiliary System

Chapter 2 Power Supply System2.1 AC/DC Distribution Unit2.1.1 Overview2.1.2 Introduction to AC/DC Distribution Unit2.1.3 AC Distribution Principle2.1.4 DC Distribution Principle

2.2 Transmission Power Supply2.3 Storage Batteries2.3.1 Built-in Storage Battery Box2.3.2 Extended Storage Battery Cabinet2.3.3 Transformer

2.4 Regulator

Chapter 3 Environment Monitoring System3.1 Overview3.2 TCU3.2.1 Overview3.2.2 Architecture and Principle

Chapter 4 Temperature Adjustment System4.1 Overview4.2 Air Conditioner4.3 Heat Exchanger

Chapter 5 Transmission Mode5.1 E1 Transmission5.2 SDH Transmission

Chapter 6 BTS Lightning Protection Grounding6.1 Overview6.2 BTS Lightning Protection Principle6.2.1 Principle and Characteristics6.2.2 AC Lightning Protection6.2.3 BTS Trunk Cable Lightning Protection6.2.4 Antenna and Feeder Subsystem Lighting Protection

6.3 BTS System Grounding6.3.1 Cabinet Internal Grounding6.3.2 Cabinet External Grounding6.3.3 AC Lightning Arrester Grounding6.3.4 Transmission Equipment Grounding6.3.5 Metal Sheath Grounding for Overhead E1 and HDSL Cables6.3.6 BTS Surge Protector Grounding

bts3012a technical manual-auxiliary system(v3.30).pdf

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