AGRICULTURAL PROCESSING, STRUCTURES, ELECTRIFICATION, AND ALLIED SUBJECTS - PART 7

Conductor

Those materials that offer very little resistance or opposition to current.

Electrons

A negative charge of electricity that is held within the orbit of the atom by the attraction of a positively-charged protons.

Volt

It is also known as the pressure and its causes electron movement.

Current

It is the movement of electrons and is measured in amperes.

Ohm’s law

The electric current flowing in a circuit varies directly with the electrical pressure and inversely with the opposition.

Distribution line

Transmission lines that begin from a sub-station and extends out over the countryside.

Service drop line

Wire connecting the post to home

True power

It is the actual power used by the circuit and is expressed in watts.

Apparent power

Power obtained by ignoring the fact that the current and the voltage are out-of-phase and is expressed in volt-amperes.

a. 3-phase supply uses less amount of copper

b. It can supply higher power requirements

c. It can be used for motors having ratings of more than 7 ½ Hp

Which of the following are reasons why polyphase power supply is superior to single-phase supply?

a. Number of poles

b. Frequency

c. Load

Which of the following are major factors in determining the rotor speed of the induction motor

Splash proof

The most commonly recommended type of motor enclosure for farm application.

50 – 80

The recommended foot-candles for rough work like wood working, foundry and storage work is:

National Electrification Administration

The government office responsible for organizing electric cooperatives in the rural areas.

a. Length

b. Cross-sectional area

c. Material

Which of the following are the factors affecting wire resistance.

Local lighting

Lighting method where the light source is relatively close to work, such as desk lamp or a lamp over a bench.

General lighting

Light source arrangement that is designed to supply a fairly uniform light intensity over large areas.

Coefficient of utilization

The ratio of the quantity of light in the working place to the quantity of light output from the source.

Btu

The quantity of heat required to raise the temperature of one pound of water by one degree Farenheight

Solar cell

The basic photovoltaic device which generates electricity when exposed to light

photovoltaic module

The smallest complete, environmental protected assembly of solar cells, exclusive of tracking, designed to generate direct-current power under sunlight

Panel

A collection of modules mechanically fastened together, wired, and designed to provide a field installable unit.

Array

A mechanically integrated assembly of modules or panels with support structure and foundation, tracking, thermal control and other components as required, to form a direct-current power requirement unit.

a. Monocrystalline

b. Polycrystalline

c. Thin-film

Which of the following are types of solar cell?

Wind turbine

A wind machine that converts wind kinetic energy into useful electrical energy.

Rotor

Which of the following is the component of the wind generating system?

Rotor

Which of the following is a component of the utility-connected system?

horizontal-axis wind turbine (HAWT)

Type of wind turbine in which the generator shaft and the axis of rotation are parallel to the wind direction.

Vertical-Axis Wind Turbine (VAWT)

Type of wind turbine where the axis of rotation is perpendicular to the wind direction.

Insulator

Materials that have very few, if any, free electrons and are referred to as non-conductors.

Electric energy

It is measured by kilowatthour meter.

Nameplate data

It provides the equipment manufacturers with a means of conveying to the customer the rated electrical value and output capacities of the equipment

Meter-disk revolution method

Method of determining watts and kilowatthours where the revolution and the Kh factor of the regular kilowatthour meter are considered.

Terminals

They refer to the two posts of a battery.

Parallel

Kind of circuit where the current that flows through one appliance does not flow through the other appliances

2.2 kw

Two twenty (220) volt line with current flowing at 10 amperes equal to

1,870 watts

A 10 ampere ventilation fan with a power factor of 0.85 was connected to a 220 volt convenience outlet. What is the power in the circuit?

1,492 watts

An electric motor has a rated horsepower of 2 hp, a rated voltage of 240 volts, and a current of 15 amperes. What is the horsepower rating of the motor in watts? Assume a motor efficiency of 85%

1755 watts

What is the input power of the motor above?

0.4875

What is the power factor of the motor above?

Volts x ampere

The power output of DC line in wattage is equal to______

Volts x ampere x power factor

The power output of AC line in wattage is equal to ______

a. Economical

b. Lower power loss

c. Small power drop

Advantage of 240 volts over 120 volts

20 amperes

Ampere capacity of AWG no. 12 wire.

Decrease

When AWG no. 12 wire is replaced with AWG no. 14, the ampere capacity will ______

Wire

Electrical conductors which are 8 mm2 (AWG #8) or smaller in size.

Cables

Electrical conductors larger than 8 mm2

Stranded wire

Consist of group of wires twisted to from a metallic string

24 ohms

A water heater draws 10 amperes at 240 volt current supply. What is the heat resistance delivered by heater

6.05 kw-hr

Determine the monthly consumption of a farm residence having the following loads. One – 1200 watts electric iron in 2 hours, one 1000-watt water heater in 3 hours and one 1300-watt toaster in 30 minutes.

250,000 circular mill

What is the size in circular mill of a cable with rating 250 MCM?

Armored cable

It is a fabricated assembly of insulated conductors enclosed flexible metal sheet primarily used for both exposed and concealed work.

Metal clad cable

It is factory assembly of one or more conductors each individually insulated and enclosed in a metallic sheet of interlocking tape of a smooth or corrugated tube and are used for service feeders, branch circuits and for indoors or out door work

Raceways

It is a wiring accessories or channels designed for holding wires, cables or bus bars which are either made of metal, plastic or any insulating materials

Convenience outlet

It is a device which by insertion establishes connection between the conductor of the flexible cord and the conductors connected permanently to the receptacle.

Receptacles

A contact device installed at the outlet for the connection of a single attachment plug

Switch board

There are free standing assembly of switches, fuses and circuit breakers which provides switching and feeder protection to a number of circuits connected to a main source.

Three phase system

Electrical system that adopted in buildings where the load exceeds 50 kva or where it is required for bigger load such as motors and machinery.

100 watts

The maximum load in watts for each household lighting outlet based on the National Electrification Code.

Ampacity

It is the ability of the wire or conductor to carry the current without overheating

. 80%

National Electrification Code provides that the ampacity of the connected load shall not exceed ___ of the amperage capacity of the conductor and the fuse.

Fermentation

It is the process of the decomposition of carbohydrates by microorganism or enzyme

Pickling

It is the preservation of food in brine or vinegar with or without bacterial fermentation.

blanching

A pretreatment procedure to keep the color and quality of vegetable before drying.

Jams

It is the process of boiling whole fruits or pieces of fruit pulp with sugar to a moderate thick consistency, without retaining the shape of the fruit

Jellies

It is a product prepared by extracting the juice from boiled fruits and then boiled with sugar and cooked to such consistency that gelatinized takes place when cooled

marmalade

It is a clear jelly which contains evenly suspended slices of fruits or peel.

Sanitation

It is aseptic practice in the preparation, processing, and packaging of food products

Antioxidants

Substances used to prevent food by retarding deterioration, rancidity or discoloration due to oxidation

Emulsifiers

Substances that modify surface tensions in the component phase of an emulsion to establish a uniform dispersion.

Ingredients

Any substance including a food additives used as a component in the manufacture or preparation of a food and present in final product.

Label

Any tag, brand, mark, pictorial or other descriptive matter, written, printed, marked, embossed or impressed on or attached to a container of food

100 deg°C

Canning temperature for fruits, tomatoes and pickles in water bath caner.

115 deg°C

Canning temperature for low acid vegetable, meat and poultry in pressure canner

Air conditioner

A refrigerated system that cleans, dehydrates and cools a compartment

The motor and compressor of the refrigeration system is separately installed

Which of the following statement is true

Entrance of the condenser tube

The highest pressure in the refrigeration system can be found at ____

Filter

The refrigeration system component after the condenser.

Evaporator

The refrigeration system component after the capillary tube.

Compressor

The refrigeration system component before condenser.

Evaporator

Lowest temperature zone in the refrigeration system.

Superheated gases

State of refrigerant at the evaporator side immediately after leaving the compressor.

Saturated gas

State of refrigerant at the evaporator side immediately before the compressor

Suva Mp 52 (r-134a)

A newly discovers refrigerant that is not harmful for ozone layer or referred to as “ozone friendly gas”

Back frost

It is term used for the overcharging of refrigerant.

Saturated gas

It is a mixture of ½ vapor and ½ liquid

Saturated liquid

It is a mixture of ½ gas and ½ liquid

19 psi

Charging pressure for refrigerator and freezer using R-12 refrigerant.

Solid CO2

A dry ice is

Cooling tower

A device used mostly in larger cooling units to cool the water that absorbs the heat from the condenser.

Lacks refrigerant

When a condenser of a refrigeration system is not cooling, what is the common trouble?

Air infiltration

It is the passage of from the outside of a leaky room caused by cracks in windows, doors, and other possible sources

R-12

Known as dichlorodifluoromethane used as primary refrigerant for refrigerator

R-22

Known as monochlorodifluoromethane used as primary refrigerant for airconditioner

Pelleting

It is the process of compressing mash feeds with the aid of live steam to produce small chunks or cylinders of feed

Crumbling

It is the process of grinding pellets into course granular from