Lap tops ?

[Pat Hasler]

How many watts is a lap top ? I have a 300w inverter in my cab, it will power, it will run large (well large for a truck) TV and a DVD player with it, but with just the lap top and nothing else running it almost burns out unless the engine is running.

[robinhood_1984]

My old 300w inverter in the UK ran my laptops fine there but when I tried doing the same here they were not up to it. It would charge the laptop with the screen closed and that was about it, as soon as you did anything on the machine the inverter would go mental and stop working. Tried on a few different inverters here, all the same.

[Pat Hasler]

Yeah, I find that if the engine is running I have no problems, as you pointed out, with the screen closed I also get no problems.

[big-al]

i am using a tablet with a iphone paired hotspot,
any sugestions on a portable hotspot?

[Pat Hasler]

I have a new larger TV in the cab but it doesn't have a DVD player, I bought one separately and to my surprise it only uses 7 watts.

[Kiowan]

Depends on the laptop, I bought an acer a few years ago and didn't think it would be so power hungry, it was 180watts so could run on my 150w inverter properly. I have a pretty powerful HP now and it only draws about 60w, would even run off one of those small cigarette lighter inverters.

It'll tell you on the laptop ac adaptor what the power consumption is, needs to be und your inverter's constant (not peak) output to work properly.

[Pat Hasler]

I understand what you are saying, I just don't now why it happens when the engine is not running ? My lap top is a large style Toshiba. I can have the TV on and plug in the laptop to use and providing the engine is running everything is ok, if I turn off the engine and the TV the inverter gets hot and starts to scream.

[Kiowan]

Sorry, totally forgot about this, when your engine is running the system voltage is around 14.3 or similar and there is more current available due to the batteries and the alternator producing power. With the engine off your battery voltage is going to be 12.5-13v and the only current you can draw is coming straight from the batteries. This is why when fully loaded your inverter is struggling.

I encounter similar issues if using high power equipment, I tend not to use my microwave with anything else running and if I use my vacuum then i'll make sure the engine is running as it has a noticeable effect on how the vacuum runs. Basically if the inverter is struggling with the engine off then you're loading too much on it at once and it's having a hard time pulling all that power from the batteries alone, won't necessarily damage it though unless its overheating and the protection circuit shuts it down. I'd also point out that my inverter is 2000 or 2500w, can't remember which and those appliances barely break 1300w but pulling that from batteries alone is a task.

[Pat Hasler]

Sorry, totally forgot about this, when your engine is running the system voltage is around 14.3 or similar and there is more current available due to the batteries and the alternator producing power. With the engine off your battery voltage is going to be 12.5-13v and the only current you can draw is coming straight from the batteries. This is why when fully loaded your inverter is struggling.

I encounter similar issues if using high power equipment, I tend not to use my microwave with anything else running and if I use my vacuum then i'll make sure the engine is running as it has a noticeable effect on how the vacuum runs. Basically if the inverter is struggling with the engine off then you're loading too much on it at once and it's having a hard time pulling all that power from the batteries alone, won't necessarily damage it though unless its overheating and the protection circuit shuts it down. I'd also point out that my inverter is 2000 or 2500w, can't remember which and those appliances barely break 1300w but pulling that from batteries alone is a task.

Thank you, very helpful, how stupid am I ? LOL.