1 / 26

Basic Electricity

Basic Electricity. Wire. Wire consists of: A conductor Copper (CU) Copper-clad aluminum Insulation Materials are based on the specific application Designed to be non-conductive . Wire and Fuse Sizing. Max fuse size Minimum Circuit Ampacity (MCA) Ground Voltage drop

tommy
Télécharger la présentation

Basic Electricity

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Basic Electricity

  2. Wire • Wire consists of: • A conductor • Copper (CU) • Copper-clad aluminum • Insulation • Materials are based on the specific application • Designed to be non-conductive

  3. Wire and Fuse Sizing Max fuse size Minimum Circuit Ampacity (MCA) Ground Voltage drop National Electric Code (NEC)

  4. Wire and Fuse Sizing • High and low voltage wire not allowed in same conduit • Conductor or wire sizing is necessary to allow enough current to flow • Sized by: • American Wire Gauge (AWG) • Amount of amperage permitted to carry • Types most commonly used: • THHN • TW

  5. Fuses and Circuit Breakers • A fuse is the simplest form of circuit protection. The word fuse derives from the Latin word meaning “to melt” • Fuses have been used almost since electricity’s beginning. The earliest type of fuse that was used was a simple bare wire that was smaller than the conductor it was protecting, and therefore would melt before the conductor was harmed Fuse Symbols Screw-in style fuse Cartridge Fuse

  6. Circuit Protection Purpose of circuit protection: 1. To protect the circuit wiring 2. To protect the loads within the circuit Protection from what: 1. Direct shorts 2. Excessive heat 3. Excessive current If these concerns are not protected, the possibilities are endless: fires, deaths, etc., which makes this issue a priority

  7. Ratings • Fuse Ratings • Current Rating • Voltage Ratings • Time Delay Rating • Delay • Standard

  8. Circuit Breakers • It is called a circuit breaker because it breaks (opens) the circuit. • The first compact, workable circuit breaker was developed in 1923. • In 1928 the first circuit breaker was placed on the market.

  9. Typical Residential Receptacles

  10. Typical Romex Nomenclature When wiring goes through a metal opening, it should be protected from wear by the use of plastic grommets, Romex connectors, or conduit connectors. Number of insulated wires Cable type Max. Voltage Rating Paper Wire Gauge

  11. Typical Romex Nomenclature Electrical boxes, furnaces, condensers, and disconnects all need connectors on high and low voltage wire to protect and to secure it Locknut Cable Clamp Cable Sheathing

  12. Wiring 120 Volt Wiring (1) Black wire (Hot) potential (1) White wire (Neutral) potential (1) Bare or Green wire (Ground) safety! 240 Volt Wiring (2) Black wires (Hot) (1) Black (1) Red wire (Hot) (1) Bare or Green wire (Ground) safety 240 VOLT If using Romex with a Black and White wire, tape the white insulation with black electrical tape to mark it as a hot wire.

  13. When installing wires to switches, receptacles, thermostats, etc., loop the wire slightly and install the loop in the direction you will tighten screw. Only strip back wire enough to make a good connection. Leaving extra bare wire is dangerous!

  14. Duplex Receptacle Switch turns receptacle on and off Receptacle stays hot. Switch turns appliance on and off

  15. Wire Nut and Split Bolt High voltage wiring can be spliced together with split bolts or wire nuts. Split bolts can be used to join multiple high voltage wires.

  16. Typical Pictorial Diagram of a Condenser • Wires must be in conduit • Conduit must have connectors on both ends • Conduit must be strapped or supported • Try to run conduit straight and at 90 degree angles

  17. Low Voltage Components The air conditioning system is comprised of high voltage and low voltage circuits What is a transformer?

  18. Thermostats Air Conditioner Thermostat Heater Condenser Heat Pump Thermostat Indoor Unit Outdoor unit

  19. Color Code For Low Voltage Thermostat Wiring

  20. Color Code For Low Voltage Thermostat Wiring

  21. Relays • A relay is a device where current going into a coil creates a magnetic effect, which switches one or more sets of contacts • Different types of relays: • Control duty relays • Fan duty relays • Contactor relays • There are 4 items you need to know about a relay or contactor: • Coil voltage • Contact voltage (maximum) • Contact amperage (maximum) • Contact type (S.P.S.T.; S.P.D.T.)

  22. Fan Center Fan Centeris a fancy name for a transformer and fan relay mounted on a 4 x 4 cover plate that can be easily attached to a 4 x 4 gang box They are primarily used with furnaces that were designed as heating-only systems (both gas and oil) that are being converted for use with air-conditioning There is typically a wiring diagram available on the fan center

More Related