Nate Core Exam Questions with Complete Solutions Graded A+

What are the five basic components to any schematic? - Answer: 1. A power supply 2. A path for the power 3. A load or component that operates from the power. 4. A switch or component that interrupts the power to the load. 5. A legend or key that explains what the various symbols and abbreviations used in the schematic mean. What are the three basic types of wiring diagrams used in the HVACR trade? - Answer: 1. The ladder diagram 2. The pictorial diagram 3. The installation diagram Describe the characteristics of a ladder diagram - Answer: 1. Provides the most helpful information for electrical troubleshooting 2.The intention of the overall schematic is to show how the circuit functions not how it actually looks. Describe the characteristics of a pictorial diagram - Answer: 1. Usually includes drawings that more closely resemble the components themselves rather than the symbols. 2. Provides the best indication of the actual positions of the components in the equipment or control panel. Describe the characteristics of an installation diagram - Answer: 1. Used primarily By the person installing equipment 2. It normally only shows what the terminal board connections are and may or may not include any internal wiring of the unit 3. Field wiring Generally represented as Dashed lines. 4. Thicker lines represent line voltage wiring(120/240 V) 5. Thin lines represent low-voltage control wiring What is a switch? - Answer: A switch is a device that interrupts power to the load. It may be manually or automatically activated by pressure, temperature or it may be an electrically controlled switch What is a load? - Answer: A load is a device that consumes power and converts it into some other form of energy Describe the side-by-side arrangement four wire diagrams - Answer: Usually arranges motors and other power consuming components on the right side of the diagram called the "load" side. The switches and other controllers are placed on the left side of the diagram called the "line"side. Describe the up and down schematic arrangement - Answer: This type of arrangement divides the schematic in to high-voltage and low-voltage sections. Normally the high voltage section is placed on the top and the low voltage is placed on the bottom of the diagram. What are the two basic configurations used in schematics? - Answer: Side by side arrangement and up and down arrangement A particular right triangle that has two equal sides. This is a? - Answer: 45°- 45°-90°right triangle Which of the following is typically represented by the two lines on the sides of a diagram? - Answer: Each leg of the line or low voltage power To change the direction of rotation of a three phase motor, it is necessary to? - Answer: Reverse any two of the motor leads The overload protection of a 10a and ma inputs of a digital used in HVAC work are? - Answer: Always the same As a general rule, a continuity check using an ohmmeter shows continuity by a reading of? - Answer: At zero or a specific resistance How is a voltmeter connected for taking a reading? - Answer: In parallel with the voltage to be measured A service company was blasted in a news article the employees were briefed in a company meeting and the majority of them nothing was done wrong and supported the company. The employees shown there were? - Answer: Loyal The federal agency that oversees the transportation of pressurized cylinder is? - Answer: DOT The dictionary defines an honest person as one who is free from fraud or deception, which of the following will hold true? - Answer: An honest person is fair and their dealings with other people A condition that must be met to make an agreement legally binding is? - Answer: The agreement must include one promise in exchange for another Which of the following expresses the difference between a feature in a benefit? - Answer: A feature is a special characteristic of a product and a benefit is the value of the customer receives from using the future According to the health and safety regulations, when climbing up or down a ladder the worker must? - Answer: Always face the ladder Refrigerant vapors in large quantities should not be inhaled since they are? - Answer: May cause heart irregularities or fainting Care should be taken before sawing basement walls that are part of the original structural construction of a home because these walls are typically? - Answer: Load bearing Describe a wet bulb thermometer: - Answer: The class thermometer with a wet piece of gauze on the end The federal agency with jurisdiction over the shipping and labeling of refrigerant is? - Answer: DOT The temperature most often used by customers when discussing human comfort is? - Answer: Dry bulb temperature