Your smartphone probably came with a car charger, and if you’re like us, you use it (though not for texting) even while you’re driving. We plug Pandora into the car’s sound system, navigate using the native navigation on our phone, and even (hands free and with careful attention to traffic) take the occasional phone call. So a constant source of power is really necessary. When we’ve got others in the car, my phone even turns into a hot spot for everybody but me to use. Which means that there’s often more than one person who needs power from the vehicle…and not just 12VDC.
What’s needed isn’t a car charger adapter, even one with dual outputs. What you need is a “Voltage Inverter” with USB outputs and plenty of watts.
Voltage inverters take the vehicle’s 12volt DC current and convert it into 115 volt AC current, and have been the go-to AC power solution for truckers and RV’ers since before they CB radios were big.
Only recently have manufacturers started including USB ports on them, but now that they’re available, don’t buy an inverter without one. Smartphones, cameras, and other USB powered devices can draw a fair amount of power and a standard car charger will just shut itself down rather than burn itself out.
How much power is enough? Well, offhand you can assume that teh USB ports will source enough to run any USB powered device on the market, but the 115 VAC gadgets can add up, so check their specs and add up their power ratings. You’ll want to do it in watts, even if what they give you us volts DC and Amps.
Conversion is easy:
(Volts)(Amps) = Watts
for example, my mini notebook’s power adapter draws 115VAC @ 1.5A or
(115VAC)(1.5A) = 173 Watts
Well within the power rating of the 400 Watt inverter here. This model also has 1000Watt surge mode, allowing it to more than double its output for a brief period to allow for start-up surges, which a lot of devices have.
One more thing. your “electrical accessory outlet” (aka cigarette lighter outlet) probably has a fuse rated at about 15 Amps. Since your electrical system is running at 12VDC, that means the plug is rated at a measly 200 Watts (12X15=200). Half the rated power of our unit, to say nothing of a surge.
What to do?
Our unit comes with two sets of wires, one for the plug and the other to connect directly to the battery. Since the unit has it’s own power protection built in, it doesn’t need a fuse. This unit also comes with a low battery alert and auto-shutdown, so it lets you know (audibly) when you’re draining the vehicle battery too much, and turns itself off to make sure you can still start up the car.
Links / Sources
- [amazon asin=B00527Z664&text=Wagan EL2003-5 400 Watt Continuous Power Inverter with 5V 2.1 Amps USB ($46.19 / Amazon.com)]