electrical safety (2)

8/8/2019 Electrical Safety (2)

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12/7/2010ELECTRICAL APPLICATIONS/SAFETY1

ELECTRICAL SAFETYELECTRICAL SAFETY

Lecture # 1


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IntroductionIntroduction

Electric Shocks

Working on energized circuits or

equipment.

Fuse replacement

Discharging machines to ground.

Earthing of equipment.


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ELECTRIC SHOCKSELECTRIC SHOCKS Short Circuit caused by accidentally

placing or dropping a metal, tool or other

conducting material across an energizedline.

Shocks can be prevented by

Awareness and positive attitude towards

electrical safety. Never take short cuts

Strict adherence to maintenance routines.


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All electrical equipment to be earthed.

Equipment should be handled in de-energized

state. All capacitors to be discharged before

working on equipment fitted with capacitors.

Insulated tools/shortening straps should be

used to discharge the equipment. Supplies are to be isolated iaw TAG OUT

PROCEDURE.


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TREATMENT OF ELECTRICTREATMENT OF ELECTRIC

SHOCKSSHOCKS Result of electric shocks may be

immediate death or unconsciousness,with

paralysis of muscles of respiration. IF CASUALITY IS BREATHING

Call for Medical assistance and do not leavethe causality unattended.

IF CASUALITY IS NOT BREATHINGCall for Medical assistance and start artificial

breathing.


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WORKING ON DEADWORKING ON DEAD

EQUIPMENTEQUIPMENT Isolate the equipment iaw BR 200(52)

Check the equipment with a voltage tester

b/w phases and b/w phases and earth.

Ensure capacitors associated withequipment are fully discharged .


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WORKING ON LIVEWORKING ON LIVE

EQUIPMENTEQUIPMENT MEOs permission must be obtained.

Work in pairs.

Wear rubber gloves if practicable. Use insulated tools.

Stand on insulating rubber mats.

Wear insulating foot wear. Be aware of the voltages that are or can be

present.


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WORKING ON LIVEWORKING ON LIVE

EQUIPMENTEQUIPMENT Do not rely on interlocks or other safety

devices.

Make sure tools do not cause short circuits.

Work with one hand if possible.


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FUSE REMOVAL ANDFUSE REMOVAL AND

REPLACEMENTREPLACEMENT REMOVAL

All users of supplies to be isolated must be

consulted. Ensure all services have been switched off and

tagged out. Exception to 115 volts where it isimpractical to switch off all the lights fed from

a set of fuses. When supplies have been isolated and the

fuses are about to be removed


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REPLACEMENTREPLACEMENT Place finger firmly in the center of the fuse

holder.

With free hand unscrew the fuse holder using thefuse key.

When fully unscrewed, firmly grasp the holder

turn head away and remove the fuse


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REPLACEMENTREPLACEMENT INSERTION

Remove empty fuse from fuse ways.

Using approved test equipment, test for

voltage across empty fuse way to ensure that

fuse way is dead.

Repeat step b on all empty fuse ways beforeinserting fuses.


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EARTHING OF EQUIPMENTEARTHING OF EQUIPMENT

All fixed, transportable or portableequipment is to be bonded to ships hull.

As hull is at EARTH zero potential henceall equipment connected will be at zeropotential.

This ensures that in the event of an

equipment casing becoming live for anyreason, personal coming into contact willnot receive shock.

electrical safety (2)

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