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Dave, that transformer can be 10 amps (in other words just because the supplier put a 2 amp transformer into the package it doesn't mean the system your installing takes 2 amps because that might have been the least expensive and available transformer). It is the camera current draw you need to consider in this application. What is the voltage and current for the camera? A simple ohms law calculation can give you the actual max current the system will have (along with a minor loss in that transformer). The bulbs at 12v/4w will be 0.333 amp (or 333ma) times the number of bulbs (if you have two of the same, it's 0.666 amps or 666ma). So, look for the current draw of the camera and you can figure out the power needed. I seriously doubt the camera takes 2 amp, you'll have to know what the camera actually uses to know what current the transformer is actually using (of the 2 amp maximum designed current flow at 5 volts out). Finally, I have no idea what Canada does about rear-end collisions because if your not backing up, the car that hits you will be liable for the damage (plus, I would not want a camera recording the damage to the driver when I went back to his car if he hit me from behind while distracted, the video would be used against me).
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