engineering quality common problem series (4) - feeder cable

7/28/2019 Engineering Quality Common Problem Series (4) - Feeder Cable

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HUAWEI TECHNOLOGIES CO., LTD.

www.huawei.com

Huawei Confidential

Engineering Quality common problems

feeder cable


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HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential

Engineering Quality Common Problems4 Feeder Cable

Page 2

The common problems of feeder cable installation

The type of problem The standards of Quality Check method

The feeder cable connector

1.The connector is not screwed well2.The VSWR is high

1The cut surface remain flat, and on the top wave of screwthread

2

It is necessary that rasp flat to the surface of kerf Feeder cableuse the rasp.

3The connector of feeder cable is made in a standard waywithout any loose connection.

Self-check

The instrument of

VSWR

The technique of connector

1.no anti-water adhesive tape

2.anti-water adhesive tape wraped no

well

3.The strap fastened no well

4.The strap have no remaining

5.The strap type choice fault

1Waterproof and sealed measures for all outdoor jumpers andfeeder cables should be correctly adopted according to

specifications.

2The labels of communication cables, feeder cables and jumpershould be stuck and tied according to specifications. The labels

should be arranged in an orderly way with same direction.

3It is necessary that black strap outdoor and white indoor.

Visual

Measurement

The distribution of feeder cable

1.no according to design

2.The radius of feeder cable bend is

small

3..no anti-water bend in front of the

feeder cable window

4.The feeder cable crossed no tidily,no fastened.

5.no feeder cable ladder

6.no ground earth

1The installation position of feeder should be accorded with thedesign document.;

2The feeder cables can not cross after distributed. In the roomthey should be neat and straight with same bend;

3The space between feeder clamps should be even and theirdirection should be same after installed. They should also be

fixed firmly without any loose connection;

4The antenna jumper and the feeder cable before the feeder

winder must have waterproof bends.5The feeder grounding clip is directly fixed on the steel sheet ofthe tower perfectly. The installation of this clip must accord with

the standard requirement. The antirust, anticorrosive and

waterproof measures are adopted for the grounding clip and

reliable connection.

Visual

Measurement


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Page 3

. The connector of feeder cable is made in a standard way without

any loose connection.

Making the connector of feeder cable


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Page 4

Problem:

The connector

has no

waterproof

mastic cement

The technique of connectorAnti-water is not sealed well

Suggestion:Use the

water-proof

mastic

cementand

PVC tape

. Waterproof and sealed measures for all outdoor jumpers and feeder

cables should be correctly adopted according to specifications.


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Page 5

Suggestion:

It is necessary

that the water-

proof adhesive

tape wrap the

connector and

waterproofmastic cement

Problem:Deficient

tape,deficient

cement,wate

r-proof seal

will be

damaged byweather.

The technique of connectorAnti-water is not sealed well

. The feeder cables should not have obvious bending and twisting

and bare copper appearance.


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Page 6

The technique of connectorNo fasten strap

Problem:

No cable

strap is

not

regular

Suggestion:

Use the

cable strap

to fasten

. The feeder cable should be fixed firmly with strapdont leave tooshort when strap is sniped.

E i i Q lit C P bl 4 F d C bl


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Page 7

The technique of connectorNo strap redundant

Problem:If no

redundant

, It is easy

to deprive

Suggestion:

New strap

with a small

redundant.

. The feeder cable should be fixed firmly with strapdont leave tooshort when strap is sniped.

E i i Q lit C P bl 4 F d C bl


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Page 8

The technique of connectorNot correct cable strap

Problem:It is not

correct

that

indoor

strap

used tooutdoor

. The feeder cable should be fixed firmly with black strap outdoorBut it should be fixed firmly with white strap indoor

Engineering Quality Common Problems 4 Feeder Cable


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Page 9

suggestion:Arrange 3

layers feeder

cable

In a clip.

Problem:It is not

correct

that

separate

layers.

Feeder cable distribution

. The feeder cable is fixed in the clip and make the 3 layers accordingto design



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Page 10

. The minimum bending radius of a feeder cable should not be lessthan 20 times of its diameter.

Feeder cable distributionBending



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Page 11

. The feeder cable before the feeder cable window must have waterproof

bends.

Feeder cable distributionAnti-water bending



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Page 12

Suggestion:

Use the clipto fix

Feeder

cable on the

tower.

Problem:

The feedercable is not

fixed of clip

Feeder cable distributionFix or not

. The space between feeder cable clamps should be even and their directionshould be same after installed. They should also be fixed firmly without any

loose connection.



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g g Q y

Page 13

. When the feeder cables is bent onthe top of a building and then

extended downward along the

wall, the protective means should

be used for the parts of contact

with the wall corner. When the

feeder cable enter to room alongthe roof, the feeder cable clips

should be used to fix the feeder

cables.

Feeder cable distributionFixed well in front of window



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g g y

Page 14

. The grounding cable is outputed from the bottom of anti-water

Feeder cable distributionGrounding cable



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HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 15

. Waterproof and sealed measures for all outdoor jumpers and feeder

cable should be correctly adopted according to specifications.. The feeder cables should not have obvious bending and twisting and

bare copper appearance.

Feeder cable distributionDon`t bare the copper



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Suggestion:

Design and

install

ladder, fix

feeder

cable on the

ladder.

Problem:

If noladder, It`s

easy that

break off or

damage

the feeder

cable.

Feeder cable distributionLadder



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. The feeder cable should be earthed at three points at least between the top of tower and the equipment room (within one meter away

from the platform on the top of tower, within one meter between the tower body and the outdoor cabling ladder, and within one meter

between the feeder cable and the feeder window). The feeder cable is tied firmly at the grounding points and has perfect waterproof

treatments.

Problem:

There is no

grounding

bar and no

grounding

earth.

Feeder cable is not grounding earth



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Appendix1The checklist of feeder cable

Problem type Check item

A The connector of feeder cable is made in a standard way without any loose connection.

A Waterproof and sealed measures for all outdoor jumpers and feeder cables should becorrectly adopted according to specifications.A The redundant part of a grounding cable or power cable or feeder should be cut and cannotbe coilled.A The feeder cables should not have obvious bending and twisting and bare copperappearance.B The minimum bending radius of a feeder cable should not be less than 20 times of its

diameter.

BWhen the feeder cable is bent on the top of a building and then extended downward along

the wall, the protective means should be used for the parts of contact with the wall corner.

When the feeder cable enter to room along the roof, the feeder clamps should be used to fix

the feeder cable.

BThe feeder cable should be earthed at three points at least between the top of tower and the

equipment room (within one meter away from the platform on the top of tower, within one

meter between the tower body and the outdoor cabling ladder, and within one meter between

the feeder cable and the feeder window). The feeder cable is tied firmly at the groundingpoints and has perfect waterproof treatments.

B The antenna jumper and the feeder cable before the feeder winder must have waterproofbends.



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B The space between feeder clamps should be even and their direction should be same afterinstalled. They should also be fixed firmly without any loose connection;

BWhen a feeder window is installed on the top of building to lead the feeder cable into the

room, it must be sealed well. The antenna jumper and the feeder cable before the feeder

winder must have waterproof bends.

B The feeder cables can not cross after distributed. In the room they should be neat andstraight with same bend;

B The grounding cable of feeder clips should extend from up to down. The angle between thegrounding cable and the feeder cable should not be more than 15 degrees.

BThe feeder grounding clip is directly fixed on the steel sheet of the tower perfectly. The

installation of this clip must accord with the standard requirement. The antirust, anticorrosive

and waterproof measures are adopted for the grounding clip and reliable connection.

BThe labels of communication cables, feeder cables and jumper should be stuck and tied

according to specifications. The labels should be arranged in an orderly way with same

direction.




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B The angle When the tower is more than 60 meters, add a grounding clip to the feeder in themiddle of the tower

BIf the length of feeder cable from the tower to the room on the roof (or cabling ladder) is

more than 20 meters, a lightning-proof protection grounding clip should be added on the

roof (or cabling rack).

CWhen the front of cabinet is parallel to the feeder cable inside the room or the back of

cabinet faces it, a sector is in line and the order of each line should be same. When the front

of cabinet is vertical to the feeder cable inside the room, a sector is in row and the order ofeach row should be same.


engineering quality common problem series (4) - feeder cable

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