Instalaciones electricas


ESCUELA SUPERIOR POLITECNICA DEL LITORAL

FACULTAD INGENIERIA EN ELECTRICIDAD Y COMPUTACION

INSTALACIONES ELECTRICAS INDUSTRIALES


Deber No. 2

PREGUNTAS CAPITULO 2
“INDUSTRIAL ELECTRICITY AND MOTORS CONTROLS




CADENA AVILA DIEGO

PROFESOR: ING. HOLGER CEVALLOS

PRIMER TERMINO 2013-2014
English:
1. IF IT IS NOT THE VOLTAGE THAT KILLS, WHAT DOES?
The current is thatkills.

2. HOW MUCH CURRENT DOES IT TAKE TO KILL?
Aproximate 200 mA can produce the death. 42 V direct current.

3. WHAT IS VENTRICULAR FIBRATION?
Is when the heart lost the cardiac rhytm, the cardiac frequency is not constant.

4. WHAT DOES GFCI STAND FOR?
It means “Ground-fault circuit interrupters”. ´This circuit helps when appears a fault currrent.
5. WHAT DOES NEC STAND FOR?
Itmeans “National Electrical Code”. This code helps to built a correct and safe electrical instalation.
6. GIVE TWO EXAMPLES OF TWO OVER CURRENT DEVICES
Breakers and fusibles.
7. HOW IS AN OVERLOAD DESCRIBED?
This happen when the motors are started or the Transformers are energized, the temperature rises by overload currents or transients. Continuous overloads can result from defective motors,overload equipment or too many load on one circuit.

8. WHAT IS A FUSIBLE LINK?
Its a link connected on the terminals of the fusible, the resistance is so low that it works as a conductor. However when destructive current occur, the link very quicky melts and open the circuit to protect the conductor and other circuit components and loads.

9. HOW IS A DUAL-ELEMENT FUSE SIZED?
When the ampererating load is permitted to be greater than te current-carrying capacitiy of the fuse, for example in a motor circuit, the dual-element can be sized up to 175% and non-time delay fused up to 300% of the motor full-load amperes. The combination of the fuses should be selected at 125% of the load current.

10. WHAT IS THE HIGHEST TRANSMISSION VOLTAGE USED TODAY?
765000 V.

11. WHAT IS THENATIONAL ELECTRICAL CODE?
Is a nationally accepted guide for the safe installation of electrical conductors and equipment.

12. WHAT IS THE PURPOSE OF UNDERWRITERS LABORATORIES?
By scientific investigation, study, experiment and tests, to determine the relation of various materials, devices, products, equipment, constructions, methods and systems to hazards appurtenant thereto or to the use thereof,affecting life and property, and to ascertain, define and publish standards, classifications and specifications for materials, devices, equipment, construction, methods and systems affecting such hazards, and other information tending to reduce and prevent loss of life and property from such hazards.

13. WHAT DOES THE CANADIAN STANDARS ASSOCIATION DO?
This association is parallel toUNDERWRITERS LABORATORIES, however CSA has more authority to remove from the market products that do not meet standards.

14. WHAT DOES OSHA STAND FOR?
“Occupational Safety and Health Act sets uniform national requirements for safety in the workplace anywhere that people are employed. In 1981 the OSHA administration sets its own code, a condensed version of the NEC containing only those provisionsconsidered related to occupational safety.
15. WHAT DO IEEE AND ANSI STAND FOR?
“American National Standards Institute” establishs equipments standards, the “Institute of Electrical and Electronics Engineers”publishes a number of books on recommended practices for the design of industrial buildings, commercial buildings, emergency power systems, grounding and the like. Both are exellent guides,although they are not in any way mandatory.

16. WHAT DOES THE OSHA COLOR ORANGE DENOTE?
Dangerous parts of machines, safety starter buttons, the exposed parts of pulleys, gears, rollers, cutting, devices, and power jaws.

17. WHY ISN’T A WATER-TYPE FIRE EXTINGUISHER USED ON ELECTRICAL FIRES?
Electrical fires are classified as class C; class C fires described as those dealing with energized...