Frequently Asked Questions – Halogen

Here are the most FAQs for the CS9300 Professional Series Landscape Lighting Halogen System. Please submit specific questions to support@pmlighting.com.

Q. How many lights can I add to each cable on the transformer?

A. The number of lights you can add to each cable run varies depending on the type of fixtures being added and the length of the Main Supply Cable. Luminaires with lower watt bulbs allow more fixtures to be added while luminaires with higher watt bulbs will decrease the total number of fixtures you can add. Also, the longer the distance of the Main Supply Cable used for the run, the lower the total wattage that will be available for fixtures. Because of these variables, you should design your system using at least 2 different Main Supply Cable runs for each set of transformer terminals to balance the load.

For transformers up to 300 watts there will be one (1) set of terminals (left and right) and for the 600 watt transformer, there will be two (2) sets of terminals (L,R & L,R). Do not exceed the maximum wattage for each set of terminals, up to 100 watts for the 100 watt transformer and up to 300 watts for the 300 and 600 watt transformers.

Q. Why does the length of the Main Supply Cable matter for total wattage?

A. In Low Voltage applications, the landscape lighting cable generates resistance on the circuit which consumes wattage that would otherwise be available for additional luminaires. Most professional landscape lighting installers recommend limiting the total wattage of luminaires on a transformer to 80% of the unit’s power rating to compensate for this additional wattage requirement. This 80% Rule is taken into consideration along with Voltage Drop in the Easy Design Chart so you do not have to worry about calculating these complex scenarios.

Q. What is “Voltage Drop”?

A. Voltage Drop is the effect on the final voltage at the luminaire based on the length of the Main Supply Cable as well as the gauge of the cable and total wattage on the cable. Heavier gauge cable helps to minimize this loss of voltage at the luminaire. Voltage drop occurs more readily on halogen systems since the wattages of the halogen bulbs is much greater than LEDs. Also, LEDs operate within a voltage range (often from 8 – 18V) so they will effectively light the same as long as the incoming voltage to the luminaire is within the range. On the other hand, halogen lamps will begin to turn more amber in color and dim as the voltage decreases so careful attention must be given to ensure there is not more voltage drop on a single run than is needed to power each run of fixtures.

Q. What gauge cable should I use when installing my system?

A. Your system comes complete with heavy duty professional 12 gauge direct burial cable. We do not recommend using any cable that is lighter than 12 gauge so avoid using cable that is 14 gauge or higher for the Main Supply Cable or T-Cable Connector. For extremely long distances, you may desire to use a heavier 10 gauge cable but this is typically not needed as long as the Easy Design Chart outline is followed. The 12/2 gauge cable should also be used to create the T-Connector Cable.

Q. What exactly is the reason for the T-Connector Cable? Why can’t I just wire the lights on the Main Supply Cable one after the other?

A. The T-Connector Cable (TCC) is essential to ensuring a balanced power load to all luminiares on the Main Supply Cable run. By using the TCC, voltage will be evenly distributed to all fixtures on the TCC run. If you wire the luminaires in sequence, one after another, voltage at the last fixture will be lower than the previous fixtures, creating an imbalance of power and light output on the system. Additionally, if the voltage drop is severe, the lamps will not light properly and may cause premature bulb failure.

Q. What do I need to add lights on my basic system?

A. The CS9300 Professional Series Landscape Lighting System comes complete with everything needed to install the 9 luminaires included in the system. This includes the Pro-Series 300 Watt Transformer, which is sized perfectly for these 9 fixtures when using the 80% Rule. If you did not upgrade the system to the CS960T 600 Watt Transformer at the time of purchase, you will need to add another power transformer to increase your system’s capabilities. Additional transformers, luminaires, and accessories are available from our retail partners.

Q. How much electricity will my landscape lighting system use each month?

A. This varies by location depending on local electricity rates but on average, a 300 watt transformer fully loaded and running 6 hours each night costs only about $6.21 per month for electricity. This system uses about one third the amount of electricity when compared to line voltage lighting making low voltage landscape lighting one of the best choices in energy efficiency. This energy efficiency characteristic coupled with solid copper fixtures makes the CS9300 system an excellent environmentally friendly choice.