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What is Electricity? 1 ATOM 2 Water Pipe Pump Water Pipe - - PDF document
What is Electricity? 1 ATOM 2 Water Pipe Pump Water Pipe - - PDF document
What is Electricity? 1 ATOM 2 Water Pipe Pump Water Pipe Wire + Wire - 3 EMF Potential Difference Between Two Points Source of Energy Electrical Pressure Voltage Friction / Static Triboelectric Chemical
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ATOM
3 Water Pipe Water Pipe
Wire Wire
+
- Pump
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EMF Potential Difference Between Two Points Source of Energy Electrical Pressure Voltage
Friction / Static Chemical Heat Light Pressure Magnetism Triboelectric Electromechanical Thermoelectric Photoelectric Piezoelectric Electromagnetic
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1910.304(e) OVERCURRENT 1910.404(e) PROTECTION
(e)(1)(i) Conductors and equipment shall be
protected from overcurrent in accordance with their ability to safely conduct current. (1926 also states that conductors shall have sufficient ampacity to carry the load)
(e)(1)(ii) Overcurrent devices shall not interrupt
the continuity of the grounded conductors unless all conductors grounded (hot) as well as grounded (neutral) are opened simultaneously
(e)(1)(iii) Disconnect required for all cartridge
fuses (over 150 volts to ground) which are accessible to other than qualified persons
(e)(1)(iv) Location in or on premises overcurrent
devices shall be readily accessible. Shall not be located where exposed to physical damage or located in the vicinity of easily ignitable material NEC Article 240-1 to 240-101
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1910.304(e) OVERCURRENT 1910.404(e) PROTECTION contd.
(e)(1)(v) Arcing or suddenly moving parts Fuses
& Circuit Breakers shall be so located or shielded that employees will not be burned or
- therwise injured by their operation
(A) through (C) - CIRCUIT BREAKERS (e)(1)(vi)(A) Circuit Breakers shall indicate
whether they are in the open (off) or closed (on) position
(e)(1)(vi)(B) Circuit Breaker handles are
- perated vertically rather than horizontally or
rotationally, the up position of the handle shall be the closed (on) position
(e)(1)(vi)(C) Circuit Breakers used as switches in
120 volt fluorescent lighting circuits, circuit breakers shall be marked “SWD” NEC Article 240-1 to 240-101
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Current - 1 amperes (a)
Voltage - E volts (v) Resistance - R Ohms (Impedence) Z ( )
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