How many amps does my inverter provide

landyacht318 wrote:


I recommend skipping the Ciggy plug whenever possible too, It is a horrible, contemptible, highly resistive electrical connection, that gets worse with age and the more current it is asked to pass. I've had one of the supposedly 'better' ciggy plug and mating receptacle buzz audibly when using a PWM dimmer on some leds, and could stop the whine/buzz simply by changing the pressure on the plug, but as soon as I let off it came back.

There are USB receptacles designed to fit the same space as a ciggy plug 12v receptacle, This one shows Amps( @5vdc) as well as voltage reaching the plug.

I considered posting about the built in USB charging ports but really didn't know exactly the OP's full intentions so ruled in favor of a Cig lighter plug style for ease of installation, portability and ease of replacement if it dies, not to mention fairly inexpensive.

In reality, 12V to 5V USB chargers will not draw enough amperage to be a issue with burning or melting plug or socket contacts.

I realize cig lighter outlet contacts are not all that great, but most vehicles have them built in and typically they work reasonably well provided you don't make a habit of drawing 80W or more from them

Dual 2.4A 5V ports should be a max of 57W (approx 4.75A) which is below the max rating of most cig lighter outlets.

Keep in mind, pretty much most of the time most devices will draw not much more than half amp to maybe 1.5A at 5V and even if it did draw 2A at 5V it would be a very short time when battery is fully depleted.

So, unless you are attempting to run a high wattage inverter with a 80W or higher load a cig lighter port WILL work fine for most loads of less than 80W.

In fact, most laptops now days come with 40W-60W power supplies so you can buy generic universal 12V to laptop power supplies (12V battery voltage in and 16V-21V output selected by the tip you install)up to 90W which will not have any issue with using a cig lighter port.. Like this.



I HAVE done that on a i7 Quad core 2ghz processor 2 in 1 laptop/tablet with touch screen with a TB SSD drive (eats battery)and it worked flawlessly!

I am not a fan of running a 12V to 120V inverter and then plug in a simple phone/tablet 5V battery charger.. Too many conversions = wasted energy in heat. Just not the right tool for phone charging.