Transformers, fuses, cable

Transformers

Transformers convert available 120 or 240 volt primary power supply to 12 volts for fixture operation. When calculating transformer size always derate total transformer capacity by 20%. TW-750 and smaller are suitable for 50/60 Hz. All transformers must be specified with approximately sized fuses and fuse holders.

Fuses and Holders

All low voltage circuits must be protected with in-line fuses properly sized to the load.

Breaker Boxes

UL Listed low voltage breaker provide a convenient and easy way to handle multiple circuit Lumascape installations. Low voltage power is brought from the transformer to the breaker box where wiring can be easily installed to screw down type contacts. Each circuit is protected by a resettable circuit breaker. Specify circuit breaker size when ordering.

Cable

Direct burial cable may be buried in the ground or hidden under chip bark, decorative stone or mulch. Cable is UL Listed for 50 volts or less and is 12 AWG two conductor stranded copper.

How to Specify:

Transformers:  Determine the total wattage by adding the wattages of all lamps in each circuit, specify the transformer accordingly. Where several circuits will be powered by a single transformer, add the combined wattages for all circuits. Always derate nominal transformer capacity by 20%.

Fuses: Divide the total circuit wattage by the operating voltage to determine the amperage, round up to the nearest size fuse.

Cable: Plan cable lengths according to the voltage drop charts.

Example: To operate 10 Waratah units with 18 watt lamps, in 2
50' runs, 5 fixtures each:
Determine total wattage: 10 x 18 watts = 180 watts
Determine total amperage: 180 watts ÷ 12 volts = 15 amps
Determine wattage per run: 5 x 18 watt = 90 watts
The correct transformer is a TW-250, the correct fuse and fuse holder is an ILH30 with FP15. Two double cable runs must be run, 200 feet of cable will be required, order 1 LC250.