Inverters for dummies

[Andrew*]

Forgive me, but I'll admit that I'm totally clueless when it comes to electrical stuff, so please walk me through this nice and slowly!

It looks like it would be a long shot to get mains into the garden permanently, but have a 70Ah leisure battery which I want to power various things off. Obviously the mount, dew heaters etc., but also a laptop and even the lawnmower sometimes to save dangling an extension from the upstairs window! I would obviously need an inverter to get the voltage up to 240V for a standard plug.

So my first question is, besides making sure the inverter has a high enough wattage to power the maximum usage, what else should I look for in a good inverter?

Is it wasteful to go from 12V up to 240V then back down to 19V via the laptop power supply? If so, is there a shortcut?

Can I run the mount directly off the battery and a laptop through the inverter simultaneously? I also have a couple of 17Ah jumpstarters, and, while I'd rather power everything from the one battery, would I be better off powering separate things from separate batteries?

Any links to products that might help me would be grand.

Thanks for your help!

[perfrej]

Yes, I would get a simple 12V to 19V inverter for the laptop and power the rest directly off the battery. I am sure Maplin has one for a few quid. Inverting it up to 240V and then use 240V to whatever adapters is silly. As for the lawn mower... They consume kilowatts of power and thus need an inverter that costs the same as a decent equatorial mount for a 20 lbs scope. Don't go there

/per

Edit: Maplin doesn't have one. You need to look elsewhere... And, remember that a 12V lead-acid battery is discharged when it reaches 11V under load. Below that you cause damage!

[Polar Bear]

Forget the lawnmower !

You will need to add up the wattage required by your setup.

This guide will walk you through the calculations http://www.batteryweb.com/pdf/inverter_battery_sizing_faq.pdf

Remember to allow for surge on power up and have some headroom built into the system.

A good quality 500w unit would be ample for a laptop, dew-heaters, mount etc.

It is not wasteful to go up to 240v and then back down for your laptop. It is best to use the original 240V ac - 19v dc for your laptop.

You will still need to charge the battery up (depending on power requirement from it an how often you intend to use it)

How far is your obsy / viewing area from the house? a long extension lead with an appropriate safety RCD (residual current device) may still be your best / most cost effective option.

Paul

[Lee M]

.... and even the lawnmower sometimes to save dangling an extension from the upstairs window!

Maybe a cheap petrol mower? I got a brand new one for £70 from ebay several years ago. Still going strong & copes much better if the grass gets a bit long.

Lee

[mallorcasaint]

Get a 4 way, 25 metre extension reel and run it out when you need it. Wouldn't be without mine.

[L8-Nite]

Forget the lawnmower !

You will need to add up the wattage required by your setup.

This guide will walk you through the calculations http://www.batterywe..._sizing_faq.pdf

Remember to allow for surge on power up and have some headroom built into the system.

A good quality 500w unit would be ample for a laptop, dew-heaters, mount etc. .................

Paul

Thanks for posting this link. I also require an inverter system, but just for observing at remote sites with a minimal amount of equipment.