Low voltage landscape Transformer
Outdoor lighting transformer installation instructions
Outdoor Lighting Transformer Instructions
1. The transformer plugs into an exterior GFI outlet. Do not use extension cords with transformers.
2. Each 300w circuit has its own circuit breaker (toggle switch) and Common (Black label that says COM). E.g. a 300w transformer has 1 COMMON TERMINAL, 600w transformers have 2 COMMON TERMINALS, 900w transformers have 3 COMMON TERMINALS, a 1200w transformer has 4 300w COMMON TERMINALS.
3. Use COMMON TERMINAL #1 until you begin to approach 300 watts of lamps used (for example when you reach 250-275 watts), then start using COMMON #2, and so on.
Connecting Home Runs to the transformer:
1. The home run cable (e.g. 10/2 or 12/2) has two wires. One wire gets connected to the COMMON TERMINAL (black label that says COM), the other wire connects to a VOLTAGE TERMINAL (the colored labels that say 12, 13,14, etc). Which VOLTAGE TERMINAL you connect that particular wire on depends on the voltage you need for that run. This is a MULTI-TAP transformer, which means you can output at a variety of voltages to compensate for VOLT DROP (see our learning area for more information on layouts and voltage drop). For example, if you have a long run of 100 feet you may need to use the 15v VOLTAGE TERMINAL in order to have 12v of power all the way out at the far away fixtures.
2. You can hook up multiple home runs to each and any of the terminals. For example you may have 6 home runs, in which case you would have 6 wires in the same COM terminal and the other half of the 10-2 wires go into the colored terminals. The VOLTAGE TERMINALS can have multiple runs/wires in each tap as well.
3. To connect a home run wire to the terminals, split the 10-2 or 12-2 wire down the middle to separate the two wires and strip half an inch of insulation off each wire. One end goes in the COM terminal, the other into a voltage terminal. Loosen the terminal screws (small flat head screw driver) and insert the wire into the terminal opening which is located at the bottom (90 degrees from the terminal screw facing the bottom of the transformer). Tighten screw to secure wire(s).
1. Low voltage wire does not have polarity, it does not matter which of the 2 wire connects to the COMMON TERMINAL and which to the VOLTAGE TERMINAL, as long as one wire goes to each.
2. Optional timers and photocells plug right into the transformer ports labeled and located inside the cabinet.
3. It is easier to see and insert the wires into their terminals when the transformer is lying on the ground. Affix all your wires BEFORE mounting the transformer.
VOLT Outdoor Lighting Transformer Troubleshooting
5 EASY STEPS
1. First check that there is power at the GFI outlet. Do not assume there is power. Check it with a Voltmeter and make sure there is ~120v AC.
2. If you have a timer please unplug/remove it. They are often a source of failure. Test the Timer Outlet inside the transformer cabinet with a Voltmeter. You should have 120v AC there as well. If you do, go ahead and plug the timer receptacle cord back into the timer receptacle outlet (the short cord inside the transformer cabinet needs to be plugged into the socket inside the cabinet) to complete the circuit or the transformer will not operate.
3. If you have a photocell installed, please remove it. Then put the jumper cable back into the photocell receptacle port to complete the circuit or the transformer will not operate. Be sure the jumper is pushed down tight. If you have a photocell in the transformer will not turn on when it is light out. Even if you cover up the photocell there is a delay (the photocell needs to be covered for about 1 minute before it will allow the transformer to turn on).
4. Make sure all the toggle switches are in the “ON” position (UP). The toggle switches are circuit breakers and can trip if there is a surge, overload or short. Sometimes the circuit breakers themselves can fail.
5. Now it’s time to test the secondary side (low voltage taps/ mutitap). Do not use the screws facing forward to test for voltage, put a voltmeter in the “garage door style opening” that hold the cable (on the underneath side of the outdoor transformer). Put one voltmeter prong on the common, the other on a tap (eg 12v tap or 15v tap). You should read anywhere from 12v AC to 22V AC depending on which tap you are testing. If you do not get any voltage, remove any wires (home run wires) from the common and the taps you are testing and try again without any load.
If you are not getting voltage at any of these points:
a. The Timer Receptacle Outlet
b. The Secondary Side (low voltage Taps/Commons).
Call Landscape Lighting World for further assistance (813) 978-3700 and let us know you have gone through the “5 Point Transformer Troubleshooting Checklist.”
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