
Lighting VOLT: the force that moves electricity • Like water pressure • 240 volts for heavy equipment
Lighting 120 volts for house voltage
Lighting 12 volts is low voltage and safe
Lighting CURRENT or AMPERAGE: the flow of electricity • Like water flow
Lighting Ohms: measure of resistance • Like friction loss in irrigation • Resistance reduces voltage
CIRCUIT PANEL • Each circuit 120 Volts • Overload, current exceeds capacity and overheats • Circuit breaker prevents overload
CIRCUIT PANEL • Circuit fuse prevents overload
LIGHTING BULBS Incandescent • Voltage through coiled filament • Converts to 90% heat and 10% • Filament evaporates tungsten (darkens bulb)
LIGHTING BULBS Halogen • Voltage through coiled filament • Halogen gas in the bulb binds the tungsten to prevent darkening
LIGHTING BULBS Halogen • <10.5 V does not heat up enough • Color shift
LIGHTING BULBS Fluorescent (CFL) • Electricity travels through argon gas • Require ballast to supply start-up current • Contain mercury
LIGHTING BULBS Solar Lights • Utilize LED light • Bluish light
LIGHTING BULBS LED (Light emitting diode) • No filament • Doesn’t heat up significantly • Efficient • Directional
LIGHTING BULBS Incandescent • 1,200 • 60 watts • $325/annually CFL • 8,000 • 12 to 15 watts • $76/annually LED • 50,000 hours • 6 to 8 watts • $32/annually LED Incandescent CFL
TRANSFORMERS • Converts 120 V to 12 V • 12 V taps (or higher) • Multiple taps
TRANSFORMERS • Wattage capacity • 300W, 600W, 900W, or 1200W • Timer and photocell
Wattage Requirements • Add the wattage of all fixture connected • Use only 80% of transformerwattage
Cable • WIRE SIZE, or AWG (American Wire Gauge) • The lower the number, the thicker the wire
Cable Single circuit cable • 12/2
CABLE Splicing cable • Quick connection
Splicing cable • Wire nuts (DBY)
Cable If wire is too small • Higher amps • Increased resistance • Increased heat • Fewer volts will get to lights