Running TV and laptop from 12v battery

ericonabike

I've recently bought a motorhome and would like to use my laptop and watch TV in it. As I'm not going to have access to mains on all occasions, I was thinking of buying an inverter to step up the leisure battery's 12v to 240v. Then I realised that a lot of the small LCD TVs use transformers, as does my laptop. I'm assuming that both step mains down to 12v. And so I intend getting a 12v lead + regulator like this one - http://www.amazon.co.uk/Visua-Stabiliser-Regulator-electronic-equipment/dp/B0044C1WHA/ref=pd_ybh_2

But I wondered if any techies reading this had any advice for or against before I invest?

Figment

You need one that will step up the voltage (if necessary) to that required by your laptop

I use one of these to power/charge my laptop in the car

http://www.maplin.co.uk/150w-laptop-car-adaptor-223723

There's also do a lower power version (120w) available which is cheaper.

Both can probably be purchased cheaper elsewhere.

Ectophile

ericonabike wrote: »

I'm assuming that both step mains down to 12v.

That's a big assumption. Laptops run on all sorts of voltages, often higher than 12V. Have a close look at the mains adaptor and the voltage should be printed on it somewhere.

fwor

Ectophile wrote: »

That's a big assumption. Laptops run on all sorts of voltages, often higher than 12V. Have a close look at the mains adaptor and the voltage should be printed on it somewhere.

Agreed - the most common voltage for laptop adaptors is around 18V.

Given that you would probably need to buy 2 separate regulator/converters for laptop and TV, it may be simpler to just go with an inverter for both, and live with the extra power losses of having to step up and then back down.

neilwoods

Most lappy's will use 19 or 19.5 volts and around 3.42 amps so a 150 watt inverter will work.

As for TV, you would have to check the power consumption, but would say a 32" may take upto 130 watt (average guess). So again 150 inverter may be ok, to run one of those items at a time, but not together.

ericonabike

Assumptions will be the death of me [hopefully not by electrocution]. As prompted here, have discovered that my laptop runs off 19v and have gone for a Maplins supply cord at £19.99 on special offer. Very much obliged for info. Will sort the TV out separately, but will be 19" max as we'll be almost sitting on top of it anyway...

Notmyrealname

Make sure you have one of those devices fitted to the motorhome that kills the accessory electrics when the battery drops to a certain level of charge otherwise you may find there's not enough charge to start the engine.

ericonabike

All the accessories etc run off the separate leisure battery - the vehicle batter is left alone unless I decide to use it to power the accessoried etc in emergency.