Download Lesson 33 electrical repair work

Lesson 33 Electrical Repair Work
CONTENTS
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1. Main Switchboard Cleaning
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2. ACB Maintenance
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3. Alternator Overhaul
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4. Boiler Feed Fan Motor O/H
1. Main Switchboard Cleaning
The following work to be carried out by the yard.
1.
All cables, connections, wires, bus-bars are to be carefully
examined for any.
2.
Check all nuts, bolts, and cable connections for tightness, all
loose connections are to be retightened.
3.
Circuit breaker contacts to be examined for arcing or contact
defects.
4.
Main switchboard holding down bolts and all equipment
securing bolts are to be checked for tightness.
1. Main Switchboard Cleaning
5.
6.
7.
8.
Means of securing cable entering or terminating in or near the
switchboard are to be examined and any loose clips are to be
replaced.
Cables are to be checked for signs of burning or deterioration.
Cleaning of the switchboard is to be done with dry compressed air
and/or vacuum cleaner. Chemical solvents should not be used.
After cleaning all moving parts are to be carefully lubricated.
2. ACB Maintenance

The following trips will be tested in the presence of
Surveyor after overhaul.
①
Voltage High/Low Alarm/Trip
②
Frequency High/Low Alarm/Trip
③
Over-current Alarm/Trip
④
Reverse Power Alarm/trip
⑤
Black out.
3. Alternator Overhaul

The work needs to be done by the yard.
A.
Allow to open, clean and inspect.
B.
Record air gap readings.
C.
Check all fittings/connections for tightness.
D.
Inspect and clean exciters
4. Boiler Feed Fan Motor O/H
①
The motor to be electrically disconnected and the coupling
removed.
②
Motor to be dismantled, end-covers & bearings removed and all
parts thoroughly cleaned for inspection. The windings are to be
megger tested and the value obtained recorded in the overhaul
record sheet.
③
The stator windings are to be dipped in insulating varnish and
baked hard and a second set of megger readings taken and
recorded.
4. Boiler Feed Fan Motor O/H
④
Any damage or defective readings are to be reported to the
Owner’s Representative
⑤
Following satisfactory testing the motor is to be
reassembled using new, yard-supplied bearings-“State brg
nos.”-and installed on board on its mounting.
WORDS
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Recondition vt.
modify
staging
terminating n.
clip
n.
deterioration
solvent
Disruption n.
megger
service
proprietary adj.
修理, 翻新
vt.
改装，改进
n.
脚手架，工作台
端接; 终端
（线）夹
n.
老化，变质
n.
溶媒, 溶剂
中断
n.
高阻表
n.
维修、保养
专卖的，专利的
Phrases

regulatory representative
行政执法部门代表

lump sum
总额，一笔总付的钱
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circuit breaker contact
断路开关/断路器接点
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distribution panel
配电盘
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voltage high/low alarm/trip
电压高/低警报/跳闸
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frequency high/low alarm/trip
频率高/低警报/跳闸
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over-current alarm/trip
电流过载警报/跳闸
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reverse power alarm/trip
逆功率警报/跳闸
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black out
全船失电
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foundation bolt
地脚螺栓
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to be dynamically balanced
动态平衡试验
Assignment
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1. Review the text.

2. Do the exercises on Page 270.