8 earthing specification for indoor macro station(01 august 2006)

Earthing GSM Base Station- DDFDDF: If the GSM base station is configured with the DDF developed by Huawei, the protection earth wire of the DDF should be connected to the indoor protect

HUAWEI TECHNOLOGIES Co., Ltd HUAWEI Confidential

Security Level:

www.huawei.com

Earthing Specification for

Indoor Macro Base Station

Course No : EQA ES-004

Composer : Engineering Quality Dept.

Table of Contents

1 General Rules

2 General Earthing Principles

3 Earthing Base station equipment

4 Earthing GSM Base Station Equipment

5 Earthing CDMA200/WCDMA base Station Equipment

6 Lightning Protection and Earthing of Antenna Feeder

7 Lightning Protection and Earthing of GPS Antenna Feeder

8 Earthing AC Power Base Station

9 Cable Distribution and Protection

10 Earthing Resistance

1 General Rules

1 This Specification is intended to regulate the engineering installation of lightning

protection and Earthing for indoor macro base station products GSM, CDMA2000 and WCDMA macro base stations all should follow this Specification

2 Special requirements of customers, if any, should be handled according to the

principles for handling problems of quality standard classification

2 General Earthing Principles

1 The battery return earthing and the protection earthing should be connected together

at such places as the main earthing terminal

2 One group of earth electrodes should be shared for earthing of a building and the Earth-termination system of external lightning protection system for the communication equipment inside the Telecommunication Site

3 Earth wires should not be intertwisted with signal cables

4 Earth wires should be made from copper core conducting wire instead of any

aluminum

5 Protection earth wires should be yellow/green interwoven, insulated by plastic with copper core inside

6 Protection earth wires should not be equipped with any fuse or switch

7 Earthing terminals should be anti-corrosive, antirust as well as firmly connected

8 The distance between the equipment of the radio base station and the user’s

earthing bar should not be longer than 30m and should be as short as possible

When it is longer than 30m, the user should set a new earthing bar nearby

3 Earthing Base Station Equipment

● Protection earthing should be required for the equipment of radio base stations The protection ground (PGND) of the base station should be connected to the protection earthing bar within the equipment room as closely as possible And the protection earth wire should be a yellow/green, insulated by plastic with copper core inside and its cross-sectional area should be no less than 16 mm2

● To ensure the equipotential connection between

the main and extension cabinets, the PGND of

them should be interconnected through a

yellow/green copper-core plastic-insulated wire

with an sectional area of no less than 6mm 2 Or

the metal shell of the two cabinets can be directly

short circuited through short circuiting metal plate

The PGND of the main and extension cabinets

should respectively to the protection earthing bar

of the equipment room through a earth wire

When equipotential connection is adopted, the

earth wire should be no longer than 2m

● Connecting DC power cable: Both the -48V DC

power cable (or +24V power cable) and the power

return cable (GND or RTN) should be connected

to the corresponding output terminals of AC/DC

power equipment from the power connecting

terminals of the cabinet, or connected to the

corresponding output terminals of DC distribution

equipment (such as the distribution panel, power

distribution frame and power distribution box)

Note that the power return cable should not be

connected to the protection earthing bar within the

equipment room

Protecti on earthi ng copper bar

Protecti on earth

Main Extension

Equipotential bonding line

£¨ or short circuiting metallic plate£©

Extension cabinet cabinet

cabinet

4 Earthing GSM Base Station- DDF

DDF:

If the GSM base station is configured with the DDF developed by Huawei, the protection earth wire of the DDF should be connected to the indoor protection earthing bar in the equipment room through a yellow/green copper-core plastic-insulated earth wire with an sectional area of no less than 6mm2

Indoor earthing barDDF of Huawei

PGND earthing terminal

4 Earthing GSM Base Station-EAC Interface

EAC interface:

The EAC interface should be protected by a lightning arrester The lightning arrester should be directly installed at the EAC interfaces of DB25 and DB37 at the cabinet top It does not need to lead a earth wire from its shell

EAC lightning arrester is a parallel connected lightning arrester To install it at the cabinet top, insert its DB male connector into the DB female socket on the cabinet Then connect the DB female connector of the lightning arrester with the

DB male connector of the cable

Requirements for installing the EAC interface lightning arrester of DB25 and DB37:

When the base station is connected with the environment monitoring instrument (alarm box) and no 24-channel extension alarm cable is configured, EAC lighting arrester of DB25 type should be installed while that of the DB37 type is dispensable When the base station is configured with a 24-channel extension alarm cable or is configured with both environment monitoring instrument and 24-channel extension alarm, EAC lightning arresters of DB25 AND DB37 both should

be installed

4 Earthing GSM Base Station- Mains Monitoring Module

Mains monitoring module

The mains monitoring module configured in the GSM base station should have a protection earthing From the metal shell of the module two protection earth wires should be led out One should be connected to PGND earthing bar (or earthing terminal) in the AC power cabinet (or power distribution frame) that supplies power to the mains monitoring module The other should be connected to the protection Earthing bar of the equipment room The protection earth wire should

be yellow/green interwoven, insulated by plastic with the copper side Its sectional area should be

no less than 3.5mm 2 (which is required by the equipotential bonding to reduce the earth potential difference between the mains monitoring module and AC power supply)

-48VGNDPGND

Power distribution box Mains monitoring module

Earthing terminal

Protection Earthing bar

of the equipment room

4.Earthing GSM Base Station -Alarm Box32

Environment monitoring instrument (alarm box)

1.When the environment monitoring instrument is connected with GSM base station by an alarm cable, a lightning arrester should be ensured for the corresponding EAC interface of GSM base station, especially when GSM base station is deployed before the environment monitoring instrument is installed

2.When the environment monitoring instrument connected with GSM base station is provided by Huawei, its –48V (or +24V) power cable, GND (or RTN) power cable and PGND (or PE) protection earth wire should be

connected to the corresponding wire terminal at the top of the GSM base station cabinet The –48V (or +24V)/ GND power cables cannot be directly connected to the DC output terminal of power supply equipment or DC power distribution frame, while the PGND wire cannot be directly connected to protection earthing bar in the equipment room

3.When the environment monitoring instrument is not provided by Huawei, its –48V (or +24V) power cable, GND (or RTN) power cable and PGND (or PE) wire should be connected to the corresponding wire terminal at the top

of the GSM base station cabinet If the user insists on connecting the power cables and PGND wire not in

compliance with the requirements of Huawei, he/she can connect the cables in his/her own way However, the personnel of Huawei should explicitly explain to him/her the disadvantages to the lightning protection

performance of the environment monitoring instrument and the base station

4.When the environment monitoring instrument not provided by Huawei adopts AC power supply, the PGND (or PE) wire of the environment monitoring instrument should be connected to the corresponding wire terminal at the top of the GSM base station cabinet If the user insists on connecting the power cables and PGND wire not

in compliance with the requirements of Huawei, he/she can connect the cables in his/her own way However, the personnel of Huawei should explicitly explain to him/her the disadvantages to the lightning protection

performance of the environment monitoring instrument and the base station

5.The PGND (or PE) wire of the environment monitoring instrument should be a yellow/ green copper-core insulated wire with cross-sectional area of no less than 3.5mm2

plastic-5 Earthing CDMA2000/WCDMA Base Station

Signal interface

During the normal operation of CDMA2000 and WCDMA base stations, the signal line of the cabinet may be led out As the lightning protection circuit of the signal interface is already designed in the equipment, no special lightning protection measures in the signal interface are necessary during the engineering installation

Accessories

The metallic shell of the functional accessories such as DDF and environment monitoring instrument configured in CDMA2000 and WCDMA base stations should be configured with protection earthing The protection earth wire should be connected to the protection earthing bar of the equipment room It should be yellow/green interwoven, insulated by plastic with copper core inside

6 Lightning Protection Earthing of Antenna Feeder

1 Lightning protection Earthing of antenna feeder outside the equipment room

A When the base station antenna is installed on a tower (including a simple tower

on the building top)

 The base station antenna should be protected with a lightning rod It should be in the protection range of the 45º angle of the lighting rod

 The antenna feeder should be laid on the cabling bridge before entering the equipment room

 The antenna feeder should also be well earthed at the places where it leaves from the tower platform at the lower end of the antenna, and where it leaves from the tower at the tower bottom as well as at the outer side of its entrance to the equipment room When no less than 60m of the feeder is laid vertically on the tower, one more earthing

in the middle of the feeder on the tower is required for the metallic sheath of the coaxial cable feeder Besides, the feeder should also be earthed at the place of 0.5~1 m above the bend where it is led to the tower through the cabling bridge at the bottom of the tower The earth wire should be black or yellow/green interwoven and its cross-sectional area should be no less than 6mm2

 Both ends of the cabling bridge should be earthed well

6 Lightning Protection Earthing of Antenna Feeder

A When the base station antenna is installed on a tower (including a simple tower on the building top)

Indoor protection earth copper bar

45 degree angle

45 degree angle

6 Lightning Protection Earthing of Antenna Feeder

B When the base station antenna is installed on the building top (where there

is no tower)

 The base station antenna should be protected with a lightning rod It should be

in the protection range of the 45º angle of the lighting rod

 The antenna feeder should be laid on the cabling bridge before entering the equipment room

 The feeder should be respectively well earthed at the top end near the antenna and at the outer side of its entrance to the equipment room If the distance between these two Earthing points is greater than 20m, it should also be earthed

on the outdoor cabling bridge The specific Earthing point should be selected at the middle between the antenna and the entrance of the equipment room so as

to facilitate operation and security implementation The sectional area of the earth wire should be no less than 6mm2 The earth wire should be either black or yellow/green interwoven

 Both ends of the cabling bridge should be well earthed The beginning of the cabling bridge should be earthed to the bonding network on the top of a building, while the end should be earthed to the earthing bar outside the equipment room

6 Lightning Protection Earthing of Antenna Feeder

B When the base station antenna is installed on the building top (there

Connect the earthing clip to

outdoor earthing bar

earthing electrode

earthing bar

equipment room Antenna Antenna rack

Cabling ladder Feeder

Feeder

Connect the earthing clip to the cabling ladder

base station equipment the outdoor earthing bar

6 Lightning Protection Earthing of Antenna Feeder

C Tower top amplifier

 The tower mounted amplifier is used to amplify the RF signals of the antenna feeder Here it does not include the active GPS antenna

 If the tower mounted amplifier configured in the radio base station is provided by Huawei, then it does not require an antenna feeder lightning arrester It is also unnecessary to earth the the metal shell of the tower top amplifier

 If the tower mounted amplifier in the radio base station is not provided by Huawei, please obtain the specific requirements for the lightning protection and earthing from the provider Huawei does not provide relevant requirements

6 Lightning Protection Earthing of Antenna Feeder

2 Lightning protection Earthing of antenna feeder inside the equipment roomThe lightning protection Earthing of the antenna feeder in the equipment room can be divided into three cases: the case that the radio base station is not configured with an antenna feeder lightning arrester, that the antenna feeder is installed on the cabinet top and that the lightning arrester is installed

on the cabling rack

A NO outdoor antenna feeder lightning arrester is configured in the radio base station

The antenna feeder does not require special lightning protection earthing in the equipment room

B The lightning arrester is directly installed at the feeder interface at the cabinet top

The protection end (“out” end or “equipment” end) of the lightning arrester should be directed at the base station Besides, the lightning arrester should

be directly connected to the coaxial connector of the antenna feeder at the cabinet top without being transferred by jumpers It does not need to lead out

a piece of earth wire

6 Lightning Protection Earthing of Antenna Feeder

C The lightning arrester is serially connected between the feeder and the jumper and installed on the cabling rack

The antenna feeder lightning arrester in the radio base station should be

earthed Its protection end should be directed at the base station Each

antenna feeder lightning arrester should be connected to the antenna feeder earthing bar through a piece of earth wire with a cross-sectional area of no less than 6mm2 The earth wires should be yellow/green interwoven and

insulated by plastic with copper core inside

Finally, a piece of earth wire with a cross-sectional area of no less than 16mm2 should be led out from the antenna feeder earthing bar to the outdoor

earthing bar outside the antenna feeder window The earth wires should be yellow/green interwoven and insulated by plastic with copper core inside