Golf Cart Lights & Light Kits:
The first thing to consider when purchasing a light package, be it just golf cart lights or a full blown system with brake lights & turn signals, is how much power is it going to consume and from where all that power will come. The problem with factory golf cart light installations is they ‘tap’ into one or two batteries in series to provide the needed current. This is OK if the electrical accessories will be for VERY occasional use. If you plan on night excursions with friends running the river banks or hunting while using high output lights and listening to the CD player you need to consider several options that will help your batteries stand up to the requirements.
You are watching: how to wire 12 volt lights to a 36 volt golf cart
BATTERY TAPS & 8-VOLT BATTERIES:The problem with ‘tapping’ into 2 batteries for a 12-volt power supply is twofold:
PROBLEM #1, 48-VOLT SYSTEMS:
In Club Car & Yamaha 48-volt systems there is no place to tap into 12-volts. You must either connect your golf cart lights to one battery, which gives you 8-volts (lights do not burn as brightly as they could but they will last a long time) or connect to two batteries, which gives you 16-volts (lights burn very brightly but they will not last as long as they should). Neither of these voltages (8 or 16) will support a CD, tape or radio system.
If you have a 36-volt electrical system then it is easy to ‘tap’ into 12-volts. Wire the ‘hot’ lead to a positive battery terminal and run the ground wire back to the negative battery terminal on the next battery over that is connected to the first one. DO NOT wire the ground to the frame of the car…run the ground wire back to the negative post on the appropriate battery. A frame ground is never recommended on any electric vehicle. See illustration below for proper wiring of 12 volt golf cart lights into a 36 volt system.
Both of the systems outlined above work very nicely for golf cart lights that will be used only once in a while. If the lights are needed for constant & long duration, this leads to the second problem.
PROBLEM #2, PREMATURE BATTERY FAILURE:
Any heavy, constant draw on these ‘tapped’ systems mentioned above will cause the battery(s) that are tapped to discharge faster than the others in the pack. The more accessories that are powered off the one or two ‘tapped’ batteries, the faster those batteries will fail. Even though the batteries recharge when the charger is connected, they never catch up to the ‘untapped’ batteries and they become chronically undercharged. Eventually, they will not be able to provide the steady voltage needed to power the accessories and the car, and they will need to replaced before the others do. Life is bad!
If you just want lights and can live with the reduced illumination of an 8-volt power supply…go for it. If you want to use the golf cart lights a lot but don’t want to spring for a voltage reducer (see below), order a pair of 36 or 48-volt head & tail lights. These golf cart lights wire up to all the batteries in the pack and draw them all down evenly. The battery charger then recharges them all evenly and life is good!
If you have to have all the golf cart lights and a CD or tape player to boot then you must consider the third option, a voltage reducer.
VOLTAGE REDUCERS (DC to DC Converters):
Use a voltage reducer to prolong the life of your batteries when adding golf cart lights or other electrical accessories. A voltage reducer will draw power evenly from your entire battery pack instead of just a couple batteries. This will ensure that the one or two batteries used to power the accessories will not die prematurely before the others due to excessive discharge of those particular batteries.
A voltage reducer, or ‘DC to DC converter’ as they are sometimes called, reduces the 24, 36 or 48 volts provided by the golf cart battery pack down to a usable 13.7-13.9 volts required by radios, CD & tape players and they can handle up to 25 amps of steady draw. A 10 Amp version cannot handle much more than 2 headlights & 2 tail lights. If you plan on installing even more 12-volt accessories (radios, fans, etc.), you will need a 25 Amp version instead.
2 head and 2 tail lights will use up 10 amps of current at 12-volts. A CD player or a tape cassette player will consume another 10 amps if added on top of a golf cart lights. That number increases significantly if high output speakers are employed. A standard radio consumes very little current as does a horn. Power consumption by a fan depends how much air it pushes. Electrical accessories made for the boating & camping (RV) industry are designed with power consumption in mind and therefore generally will consume less current than accessories for the auto & truck market where the alternator can produce plenty of juice for the many accessories common to those vehicles. When you design the accessory package for your golf cart think about now and think about what you might want down the road a year or so. Order accordingly.
Why do you need a voltage reducer? Consider this: A 10 amp draw from the golf cart lights, another 10 amp draw from the CD player and all of this current coming out of one or two batteries. No big deal if this draw is VERY occasional, but what about security or airport operations that have 24/7/365 power needs from the battery pack for lights, strobe, warning buzzer & communications in addition to powering the electric vehicle around the grounds? If all the current for the electrical accessories comes out of 1 or 2 batteries, then those batteries will run out of power long before the others. This wouldn’t be too bad if they recharged fully but they don’t! Initially you won’t notice those two batteries do not come up to full recharge as the others do but soon the two overused batteries will fail prematurely.
This is the dynamic:
The 1 or 2 overused batteries never do come back up to full charge like the others. After each day of extra heavy use (remember they have to help power the car AND all of the accessories) they do recharge but they never catch back up to the other batteries and over time they wear down further & further until they can no longer provide the needed power to do their job. Now the car performs well fresh off of the charger but the overused batteries quickly give out. The electric vehicle is not designed to operate on less than a full set of batteries so if one or two give out, so goes the vehicle. Longer charging times will not help. If this sounds like you…you need a voltage reducer.
By Jack Triolo