Mec112

Electrical Workshop Pracrice & Technology

Comprehensive information on electrical hazards, tools, and safety procedures

⚡1. Common Causes of Electrical Hazard

Faulty or Damaged Wiring: Exposed wires, loose connections, and deteriorated insulation.
Overloaded Circuits: Plugging too many devices into a single outlet, causing overheating.
Water Contact: Using electrical equipment with wet hands or near water sources.
Improper Grounding: Lack of a proper earth connection, preventing safe fault current dissipation.
Damaged Power Tools & Equipment: Cracks in casings, frayed cords, or broken plugs.
Contact with Overhead Power Lines: During construction, tree trimming, or using long ladders.
Using Incorrect Fuse Ratings: Replacing a fuse with one of a much higher rating, removing its protective function.

🔌2. Electrical Definitions

a) Electric Earthing (Grounding)

The process of connecting the metallic (non-current carrying) parts of an electrical installation (like equipment chassis) to the earth (the ground) via a thick conductor. This provides a safe path for leakage or fault current to flow into the ground, preventing electric shock.

b) Earth Continuity Conductor

A conductor that connects the metal casing of an electrical appliance or device to the earth terminal of the installation. It ensures a continuous, low-resistance path for fault current to travel to the earth electrode.

c) Earth Electrode

A metal rod, plate, or pipe buried deep in the ground to which the earth continuity conductor is connected. It makes direct physical contact with the earth, providing the final path for the fault current to dissipate safely.

🛠️3. Differences Between Machine Tools and Hand Tools

Feature	Machine Tools	Hand Tools
Power Source	Powered by electricity, compressed air, or an engine.	Powered solely by human muscle force.
Precision & Speed	Generally higher precision and much faster operation.	Lower precision and slower, dependent on user skill.
Complexity & Cost	More complex in design, operation, and maintenance; higher cost.	Simpler in design and operation; generally lower cost.
Application	Used for heavy-duty, repetitive, and high-volume tasks (e.g., milling, drilling).	Used for light-duty, custom, or detailed work (e.g., hammering, screwing).
Skill Requirement	Often require specialized training to operate safely and effectively.	Require basic skill and are generally easier to use.

⚠️4. Ways to Prevent Electrical Shock

Always de-energize (switch off and isolate) circuits before working on them.
Use the Lockout-Tagout (LOTO) procedure for maintenance.
Ensure proper grounding and earthing of all equipment and outlets.
Use Ground Fault Circuit Interrupters (GFCIs/RCDs) in wet or damp locations.
Inspect tools and cords for damage before use.
Avoid working with electricity in wet conditions.
Wear appropriate Personal Protective Equipment (PPE) like insulated gloves and shoes.

🏠5. Necessity of Earthing in Electrical Installation

Personal Safety: Protects humans from severe electric shock by providing a safe path for fault current.
Equipment Protection: Prevents damage to appliances and wiring by allowing excessive current to flow, which should blow a fuse or trip a circuit breaker.
Voltage Stabilization: Helps to maintain the voltage stability of the system under normal and fault conditions.
Prevents Fire Hazards: By quickly disconnecting the power during a fault, it prevents overheating and potential fires.
Protection from Lightning: Provides a path for high-voltage lightning strikes to dissipate safely into the ground.

🫁6. Mouth-to-Mouth Resuscitation Technique

Note: For untrained individuals, hands-only CPR is recommended. However, the standard technique for trained responders is:

Ensure Safety: Check the scene for danger.
Check Responsiveness: Tap and shout, "Are you okay?"
Call for Help: If unresponsive, call emergency services and get an AED.
Open Airway: Tilt the head back and lift the chin.
Check for Breathing: Look, listen, and feel for no more than 10 seconds.
Give Rescue Breaths:
- Pinch the person's nose shut.
- Seal your mouth over their mouth.
- Give two slow breaths (each about 1 second), watching for the chest to rise.
Begin Chest Compressions: After two breaths, immediately begin chest compressions (30 compressions to 2 breaths).

🧯7. Types of Fire Extinguisher (Based on Fuel/Class)

Class A: For ordinary combustibles (Wood, Paper, Cloth). Water or Foam type.
Class B: For flammable liquids (Gasoline, Oil, Grease). CO₂ or Dry Chemical type.
Class C: For electrical fires (Live Electrical Equipment). CO₂ or Dry Chemical type. (Non-conductive)
Class D: For combustible metals (Magnesium, Titanium). Dry Powder type.
Class K: For cooking oils and fats (Commercial Kitchens). Wet Chemical type.

🔧8. Different Wiring Methods

Cleat Wiring: Uses porcelain cleats to hold wires on walls. Temporary and outdated.
Conduit Wiring: Wires are run through metal or PVC pipes (conduits) for maximum protection.
Batten Wiring (TRS/CTS): Cables are run on wooden batten and held by clip saddles.
Surface Raceway Wiring: Wires are run inside plastic or metal channels mounted on the surface of walls.

🧰9. Common Tools Found in an Electrical Tool Box

Insulated Screwdrivers (Flat & Phillips)
Linesman Pliers / Combination Pliers
Wire Strippers / Cutters
Voltage Tester / Multimeter
Electrical Tape

🔋10. Insulating and Conducting Materials

Insulating Materials (High Resistivity):

Rubber, PVC (Polyvinyl Chloride), Glass, Porcelain, Dry Wood.

Conducting Materials (Low Resistivity):

Copper, Aluminum, Silver, Gold, Iron.

⚖️11. Conductor Vs Insulator

Property	Conductor	Insulator
Electrical Conductivity	Very High. Allows electric current to flow easily.	Very Low. Does not allow electric current to flow.
Electrical Resistivity	Very Low. Offers little opposition to current flow.	Very High. Offers strong opposition to current flow.
Primary Function	To carry or transmit electric current.	To block or prevent the flow of electric current.
Example	Copper wire in a cable.	Rubber or PVC sheath covering the copper wire.

💡12. Sketch of a 2-Way Lamp Switch

A 2-way switch allows you to control a single light from two different locations (e.g., at the top and bottom of a staircase).

Common

[LAMP]

Neutral

[SW1]

-----/ ------

[SW2]

-----/ ------

Live

------------

Explanation: The Live wire is connected to the Common terminal of the first switch (SW1). Two "traveler" wires (L1 and L2) connect SW1 to SW2. The Common terminal of SW2 is connected to the Lamp. The other terminal of the Lamp is connected to the Neutral. Toggling either switch will break or complete the circuit, turning the light ON or OFF.

📦13. Main Function of Pattress and Junction Box

Pattress Box (or Back Box): The fixed box set into a wall or surface whose primary function is to house and protect the electrical components (like switches or sockets) and the cable connections behind them.
Junction Box: An enclosed box used to safely contain and protect the connections (splices) of multiple electrical cables, preventing contact with people or flammable materials and providing mechanical protection.

🔍14. Purpose of Electrical Tests

a) Continuity Test

To verify that a complete electrical path exists in a conductor or circuit. It checks for breaks (opens) in a wire, a fuse, or a connection. A multimeter set to continuity will beep if the path is unbroken.

b) Polarity Test

To ensure that electrical connections are made correctly—specifically, that the Live (Line) and Neutral wires are not swapped. Correct polarity is crucial for the safe operation of switches, fuses, and equipment.

⚡1. Abubuwan Da Suka Fi Haifar Da Hadarin Lantarki

Lalatattun Wayoyi Ko Lalacewa: Bayyananniyar wayoyi, rassan haɗin kai, da lalacewar rufi.
Yawaitar Wutar Lantarki: Tosa na'urori da yawa a cikin mahaɗar guda, yana haifar da zafi fiye da kima.
Haɗuwa da Ruwa: Yin amfani da kayan aikin lantarki tare da rigar hannu ko kusa da tushen ruwa.
Kuskuren Ginin Ƙasa: Rashin ingantaccen haɗin ƙasa, yana hana zubar da ingantaccen kwararar laifi.
Lalacewar Kayan Aikin Wutar Lantarki: Tsagewa a cikin akwati, lalacewar igiyoyi, ko karyewar fetoji.
Haɗuwa da Layukan Wutar Lantarki: Yayin gini, datsa bishiyoyi, ko amfani da tsayin sanduna.
Yin Amfani da Ƙimar Fyuz Ba Daidai Ba: Maye gurbin fyuz tare da wanda ya fi girma, yana cire aikin kariyarsa.

🔌2. Ma'anar Lantarki

a) Ƙasar Lantarki (Ƙasar Lantarki)

Tsarin haɗa sassan ƙarfe (waɗanda ba sa ɗaukar kaya) na shigarwar lantarki (kamar chassis na kayan aiki) zuwa ƙasa (ƙasa) ta hanyar babban madugu. Wannan yana ba da hanya mai aminci don ɗigon ruwa ko kwararar laifi don karkata zuwa ƙasa, yana hana girgiza wutar lantarki.

b) Madugun Ci gaba na Duniya

Madugu wanda ke haɗa akwatin ƙarfe na na'urar lantarki ko na'ura zuwa tashar ƙasa na shigarwa. Yana tabbatar da ci gaba, ƙaramar hanyar juriya don kwararar laifi don tafiya zuwa lantarki na lantarki.

c) Lantarki na Duniya

Wani sandan ƙarfe, faranti, ko bututu da aka binne zurfi a cikin ƙasa wanda aka haɗa madugun ci gaba na duniya. Yana yin hulɗa ta jiki kai tsaye tare da ƙasa, yana ba da hanyar ƙarshe don kwararar laifin ya watse lafiya.

🛠️3. Banbanci Tsakanin Kayan Aikin Injiniya Da Kayan Hannu

Siffa	Kayan Aikin Injiniya	Kayan Hannu
Tushen Wutar Lantarki	Ana kunna shi da wutar lantarki, matsanancin iska, ko injin.	Ana kunna shi da ƙarfin tsokar ɗan adam kawai.
Daidaici & Sauri	Gabaɗaya mafi girman daidaito da aiki mai sauri.	Ƙananan daidaito da jinkiri, ya dogara da ƙwarewar mai amfani.
Rikitarwa & Farashi	Mafi rikitarwa a cikin zane, aiki, da kulawa; farashi mafi girma.	Mafi sauƙi a cikin zane da aiki; gabaɗaya ƙananan farashi.
Aikace-aikace	Ana amfani dashi don ayyuka masu nauyi, maimaitawa, da babban girma (misali, niƙa, hakowa).	Ana amfani dashi don aikin haske, na al'ada, ko daki-daki (misali, guduma, dunƙulewa).
Bukatar Fasaha	Sau da yawa suna buƙatar horo na musamman don yin aiki lafiya da inganci.	Suna buƙatar ƙwarewar asali kuma gabaɗaya suna da sauƙin amfani.

⚠️4. Hanyoyin Hana Girgiza Wutar Lantarki

Koyaushe kashe wutar lantarki (kashe kuma ware) da'irori kafin yin aiki a kansu.
Yi amfani da tsarin Kulle-Alama (LOTO) don kulawa.
Tabbatar da ingantaccen ƙasa da ƙasa na duk kayan aiki da mahaɗa.
Yi amfani da Masu Katsewar Lantarki na Ƙasa (GFCIs/RCDs) a cikin wurare masu ɗanshi ko danshi.
Duba kayan aiki da igiyoyi don lalacewa kafin amfani.
Guje wa yin aiki tare da wutar lantarki a cikin yanayi mai danshi.
Saka kayan kariya na mutum (PPE) masu dacewa kamar safar hannu da takalma.

🏠5. Larura na Ƙasar Lantarki a cikin Shigarwar Wutar Lantarki

Lafiyar Mutum: Yana kare mutane daga mummunan girgiza wutar lantarki ta hanyar samar da hanya mai aminci don kwararar laifi.
Kariyar Kayan Aiki: Yana hana lalata na'urori da wayoyi ta hanyar barin kwarara mai yawa, wanda ya kamata ya busa fyuz ko kuma ya kawar da na'urar katsewar kewaye.
Ƙarfafan Ƙarfin Wutar Lantarki: Yana taimakawa wajen kiyaye kwanciyar hankali na wutar lantarki na tsarin a ƙarƙashin yanayi na al'ada da na laifi.
Yana Hana Hadarin Wuta: Ta hanyar cire wutar lantarki da sauri yayin laifi, yana hana zafi fiye da kima da yuwuwar gobara.
Kariya daga Walƙiya: Yana ba da hanyar babban ƙarfin lantarki na walƙiya don watsewa lafiya cikin ƙasa.

🫁6. Dabarun Taimakon Baki zuwa Baki

Bayanin kula: Ga waɗanda ba su da horo, ana ba da shawarar CPR na hannu kawai. Duk da haka, daidaitaccen dabarun masu amsa da suka horar da su shine:

Tabbatar da Aminci: Duba wurin don hatsari.
Duba Amsa: Matsa kuma ku ihu, "Kana lafiya?"
Kira don Taimako: Idan ba a amsa ba, kira sabis na gaggawa kuma ku sami AED.
Bude Hanyar Iska: Karkatar da kai baya ka ɗaga haɗaɗɗiyar.
Duba Numfashi: Duba, saurara, kuma ji na bai wuce seconds 10 ba.
Ba da Iskar Ceto:
- Matsa hancin mutum a rufe.
- Rufe bakinka a kan bakinsu.
- Ba da iska jinkirin iska guda biyu (kowanne kusan daƙiƙa 1), kallon kirji ya tashi.
Fara Matsawa Ƙirji: Bayan iskar iska guda biyu, nan da nan fara matsa ƙirji (matsawa 30 zuwa iskar iska 2).

🧯7. Nau'in Kashe Wuta (Dangane da Man Fetur/Aji)

Aji A: Don gurɓataccen gurɓataccen abu (Itace, Takarda, Yadi). Ruwa ko kumfa iri.
Aji B: Don ruwa mai ƙonewa (Man Fetur, Mai, Maiko). CO₂ ko Dry Chemical iri.
Aji C: Don gobarar lantarki (Kayan Aikin Lantarki Masu Rai). CO₂ ko Dry Chemical iri. (Maras lantarki)
Aji D: Don karafa masu ƙonewa (Magnesium, Titanium). Bushewar foda iri.
Aji K: Don man dafa abinci da kitsen (Kitchen Kasuwanci). Rigar Sinadari.

🔧8. Hanyoyin Waya Daban-daban

Cleat Wiring: Yana amfani da ƙwanƙwasa don riƙe wayoyi a bango. Na wucin gadi kuma ya tsufa.
Conduit Wiring: Ana gudanar da wayoyi ta cikin bututun ƙarfe ko PVC (magudanar ruwa) don mafi girman kariya.
Batten Wiring (TRS/CTS): Ana gudanar da kebul a kan batten na katako kuma ana riƙe su ta hanyar sirdi.
Surface Raceway Wiring: Ana gudanar da wayoyi a cikin tashoshi na filastik ko ƙarfe da aka ɗora a saman bango.

🧰9. Kayan Aikin Gama gari da Ake Samu a cikin Akwatin Kayan Aikin Lantarki

Insulated Screwdrivers (Flat & Phillips)
Linesman Pliers / Combination Pliers
Wire Strippers / Cutters
Voltage Tester / Multimeter
Electrical Tape

🔋10. Kayan Keɓe da Gudanarwa

Kayan Keɓe (Babban Juriya):

Robo, PVC (Polyvinyl Chloride), Gilashi, Porcelain, Busasshen Itace.

Kayan Gudanarwa (Ƙananan Juriya):

Jan ƙarfe, Aluminum, Azurfa, Zinariya, Ƙarfe.

⚖️11. Madugu Vs Insulator

Dukiya	Madugu	Insulator
Gudanar da Wutar Lantarki	Yana da girma sosai. Yana ba da damar wutar lantarki ta gudana cikin sauƙi.	Yana da ƙasa sosai. Ba ya barin wutar lantarki ta gudana.
Juriya na Lantarki	Yana da ƙasa sosai. Yana ba da ƙaramar adawa ga kwararar halin yanzu.	Yana da girma sosai. Yana ba da adawa mai ƙarfi ga kwararar halin yanzu.
Aikin Farko	Don ɗauka ko watsa wutar lantarki.	Don toshe ko hana kwararar wutar lantarki.
Misali	Wayar tagulla a cikin kebul.	Robo ko kumbon PVC da ke rufe wayar tagulla.

💡12. Zane na Lambu Wuta Hanya Biyu

Mai canzawa hanya biyu yana ba ku damar sarrafa haske guda daga wurare daban-daban guda biyu (misali, a saman da ƙasan benci).

Common

[LAMP]

Neutral

[SW1]

-----/ ------

[SW2] -----/ ------

Live

------------

Bayanin: Wayar Live an haɗa ta zuwa tashar Common na canjin farko (SW1). Wayoyi "matafiya" guda biyu (L1 da L2) suna haɗa SW1 zuwa SW2. Tashar Common na SW2 an haɗa shi da Lambu. Sauran tashar Lambu an haɗa shi da Neutral. Canza kowane canji zai karya ko kuma ya cika da'ira, yana kunna haske KASHE ko KASHE.

📦13. Babban Aikin Pattress da Akwatin Junction

Akwatin Pattress (ko Akwatin Baya): Akwatin da aka kafa a bango ko saman wanda babban aikin sa shine gida da kare abubuwan lantarki (kamar masu canzawa ko soket) da haɗin kebul a bayansu.
Akwatin Junction: Akwatin da aka rufe da ake amfani da shi don aminci ya ƙunshi da kare haɗin gwiwar kebul na lantarki da yawa, yana hana haɗuwa da mutane ko kayan wuta da kuma samar da kariyar injina.

🔍14. Manufar Gwaje-gwajen Lantarki

a) Gwajin Ci gaba

Don tabbatar da cewa akwai cikakkiyar hanyar lantarki a cikin madugu ko kewaye. Yana duba karyewar waya, fyuz, ko haɗin kai. Multimeter da aka saita zuwa ci gaba zai yi ƙara idan hanyar ba ta karye ba.

b) Gwajin Iyakacin Duniya

Don tabbatar cewa an yi haɗin lantarki daidai - musamman, cewa Live (Layi) da Neutral wayoyi ba a musanya su ba. Daidai iyakacin duniya yana da mahimmanci ga aikin aminci na masu canzawa, fyuz, da kayan aiki.