If you think your stock alternator is able to power anything you throw at it, think again. Even the simplest of things like safety beacons have been known to kill off stock alternators, let alone safety lights, light bars or winches. The alternator as a component, generally taken, is very underrated and quite often overlooked. It’s not the first thing that pops up in people’s mind as a necessary upgrade. But, it is a vital one.
There are a few concerns when it comes to exceeding the capacity of your alternator, some of which are more serious than others. For starters you might start experiencing light flickering, a dimmer instrument light panel, dim gauges and even lose lights completely. Alternators are manufactured to have a 10-15 percent reserve in case people want to fit accessories to their vehicles, but they are in no way adequate to power lots of safety lights and high output winches. You may get away with and additional light or two but as a general rule, you don’t want to exceed anything beyond that with a stock alternator. If you do, you could be in for a lot of trouble. Worst case scenario is that your alternator runs everything just fine, only to die while on the road and leave you stranded.
Trucks towing trailers or other vehicles need to be fitted with a decent amount of markers lights to ensure the safety of themselves and all of the other road users. Not only is it not safe to do so, but it is illegal. You might get away with it during the day, although we doubt it, but as soon as it gets darker you’ll find yourself struggling. It’s therefore vital to have multiple marker lights. Not doing so is irresponsible and illegal, and it could land you jail time or worse, injured or killed.
To run multiple lights however, you will need some special requirements. Not a lot, but you will need some upgraded parts. In most cases, a high amp alternator. You might already know what a high amp does, but just in case you don’t, here it is.
A high amp alternator raises the amount of available amps for your system. The system here being the total sum of all the things requiring electricity in your vehicle. This includes anything from lights to horns and even power seats. Contrary to popular belief, a high amp alternator isn’t just needed in the case of a high output audio system or a racecar with a lot of systems. It’s useful for even something as simple as a light bar or a few marker lights.
The best thing is that you can never have such a thing as an alternator with too much amps. The sky’s the limit here really, as not using the entire capacity of the alternator just means that it will run smoother and always have a reserve in case you need it. To make sure you’re not abusing your stock one (if you have modifications to the vehicle), use an online calculator to determine how much amps you’re using and check out your alternator’s rated capacity. If it’s insufficient, immediately replace it.