Is an Ac to Dc converter safe to use in a Tesla?

[ryan48659]

So i live on the road and i need a way to charge my laptop. My laptop charger is 150w so i found this 150w converter. Is this safe to use, Would this harm the battery of the car in anyway? Also if theres any techs, would it be safe for the laptop too?

 

[bradtem]

I asked what the laptop requirements are because there could be another way of powering it without needing the DC->AC->DC conversion that using an inverter with the laptop's original AC power supply will cause or using a low-wattage AC power supply but with some tradeoffs. It really depends upon exactly what the OP is using for a laptop.

I believe I have about a hundred ThinkPad laptops; inventory control is not my forte - I lost count several years ago. Most of them are functional but I do have some parts machines as well. In my previous life I was a member and then co-admin at forum.thinkpads.com. Everything from old 600-series systems (600E, 600X) to the W520 I'm currently typing on. Power requirements of my systems have shifted over the years from 12VDC to 20VDC. Almost of the ThinkPad power supplies that I own have a coaxial (barrel) plug to deliver power - a couple of them have that rectangular plug but I think that's mostly for the docking stations. I don't own any laptop which uses the USB-C power connection. Mainly because I stopped acquiring ThinkPads once they ruined the keyboard layout (turning away from the classic 7-row arrangement but that's just IMO).

Anyway, back to the W520 I'm on.... The power supply I'm using right now is rated as 135W, outputting 20VDC at 6.75A. However the preferred supply of the W520 is 170W, or 20V at 8.5A. Using the lower wattage supply means that the computer is not running as fast as it can and/or charging of the battery will take longer. The laptop shows the power requirements on the bottom label as: 20V 6.75A/8.5A.

The OP might be able to get away with using a lower wattage power supply. If so, then it might be possible to use a boost converter; a DC->DC circuit which provides an output voltage greater than the input voltage, assuming the laptop requires something greater than 16V. That would take the 12V/16V DC input and boost it up to what the laptop needs. Typically those converters don't have a high current capability but I believe there are some which can reach 5A.

The W520 is a workstation class laptop, more of a desktop in small package, so it uses much more power than most laptops. While I think you still could power it from a lenovo car charging adapter, perhaps avoiding using it in power intensive modes at the same time as recharging its battery near empty, that might not be the best laptop for use in a car.

 

[RayK]

The W520 is a workstation class laptop, more of a desktop in small package, so it uses much more power than most laptops. While I think you still could power it from a lenovo car charging adapter, perhaps avoiding using it in power intensive modes at the same time as recharging its battery near empty, that might not be the best laptop for use in a car.

Yes, well the W520 is known for being a power hog, the OP's laptop power supply is supposed to be rated (150W) much like what I'm using (135W/170W).

 

[zroger73]

I see that the W520 comes with a 170-watt AC adapter, so that must be the maximum power consumption of the laptop under 100% load.

It appears this unit uses a 94 Wh battery and achieved over 9 hours of operation while browsing the internet over Wi-Fi which means the unit used about 10 watts continuously.

 

[bradtem]

I see that the W520 comes with a 170-watt AC adapter, so that must be the maximum power consumption of the laptop under 100% load.

It appears this unit uses a 94 Wh battery and achieved over 9 hours of operation while browsing the internet over Wi-Fi which means the unit used about 10 watts continuously.

That will be average. But in the rare event that you run software that maxes out all your CPU cores and all your GPUs, it would draw a great deal more. The other main load, as I noted, is charging the battery when it is empty. Doing all those at the same time, with screen on full brightness and full power peripherals in every USB, probably would not draw 170w, but they would have left a bit of margin.

In reality, you won't do all these things at once, not sitting in your car. If somehow this could happen, you would just accept that if the battery is dead, you have to not make heavy use of the computer for a short time. It's not a burden.

 

[PianoAl]

I had an inverter hooked up to my old Model S and it worked flawlessly for 2 years. Used it every day to power a microwave and other things.

I have to know the circumstances under which you'd need to use your car to power a microwave every day.

 

[RayK]

I have to know the circumstances under which you'd need to use your car to power a microwave every day.

Hot coffee in the morning?

 

[David99]

I have to know the circumstances under which you'd need to use your car to power a microwave every day.

I spend so much time traveling in my car that I had a small fridge and a microwave. Just makes things convenient.