Notes to consider and common mistakes
I have written this page made to stop the hudreds of emails asking the same questions. We will edit it to a better page as we go along.

Sizing your system.
This is very difficult to do and you should speak to your local experienced installer first. Sizing a system via email or via phone is difficult and time consuming. And can lead to massive mistakes.
If unsure you will need to do some homework.
Make sure you know the wattage of everything before you size a system. write it all down and do the maths twice to make sure. Then make sure you allow a fudge factor for heat, startup loads etc. Some startup loads can be double the rated power capacity. Also some rated watts are not the load watts. ie microwaves.

You will need to know your maths. Remember 100amps for 1000 watts at 12VDC is a rough guide most people use.

A car battery is 60 - 80amps at 20hour discharge rate. Put a 1000watt inverter on it and you will be lucky to get 80% of that. As the faster you discharge a bettery the less amps you get out of it. FACT.
A 100AH battery is usually 100AH at 20hour rate. So if you evenly discharge the battery over 20hours you get 100Amps. discharge it at 4 times the amps it is NOT divide by 4. You will get  alot less depending on the battery. Ask your manufacturer for a discharge chart that shows how many amps at the 5 hour or 10 hour rate.

Microwaves.
An 800 watt microwave is a 800watt cooking power. power consumption can be from 1200watts to 2000watts.
Microwaves KILL your amps big time. As they chew massive amounts of power. Would only recomment using a microwave in emergency or with a generator or shore power assisting. Unless you have a minimum of 4 100AH batteries to even out the load.

Fridges.A 300watt 240volt bar fridge can draw massive amounts of power when the compressor kicks in. Especially on hot days with an old fridge. So 1000watts is not unusual power surge. That is why some cheap inverters don’t start fridges or air conditioners. Victron Energy inverters are TRUE power inverters that will start a fridge.My advice. BUY A 3 WAY Fridge. Or at least a 2 way fridge. Gas and 12V.
DON’T buy a fridge that is not a compressor fridge.
Cheap thermal transfer fridges use MASSIVE amounts of power. Called Eutectoid fridges and thermal couple fridges can use 8 to 20 amps per hour and cannot get cold enough for most people. But hey they are cheap. Pay nothing for the cheap fridge but tripple the price on batteries and chargers??  False economy realy.

Cheap inverters
Some cheap inverters may say they are 1000watts. But that is 1000watts for 10 seconds not FULL TIME LOAD. Some are 1000watts for 20 mins and most people don’t notice until it is a hot day over 30deg and the unit shuts down because they overheat. Ours are TRUE RATED WATTS AND VA.
This is very common with very cheap inverters. Not all of them but most of the el cheapo inverters are junk. Think of this. $2000 laptop. $50 inverter. Repair bill when the non sine wave  inverter breaks the laptop and NO WARRANTY. Read your instruction manuals. Some manufacturers are so sick of cheap inverters damaging their equipment they now will void your warranty if damage occurs. Especially if you are using a NON sine wave inverter. All victron inverters are full sine wave inverters with clean power. If it is nice and light then it is not a true sine wave as a general rule.

Cheap inverters and dirty power.
Cheap inverters don’t filter power properly and some even put bad waveforms into your equipment to the point where it can void your warranty. Especially on laptops.Watts and VA.. what the?????2000VA is 2000 Volt Amps. Which is around 1800watts. Its about maths and Volts and power etc. so read the manual of the cheap inverters. Some say they are 2000va in one section then claim 2000watts on the box. Yeah. 2000watts for 5 seconds. There should be (But unfortunately there isnt) a law governing how people advertise power ratings on products. Be smart. Do your homework.

If you ring around and get proper designs made up for your system and they all come in at $5000. don’t expect someone to do it for $2000 as there is not a huge margin in technology these days. If you get one quote that is so cheap there is a reason. Like they are using cheap parts and maybe cables that are to small. This is a massive problem. High amp high quality cables and connectors are not cheap. But worth the investment.

REMEMBER---> A 12V 2000watt inverter uses 200 amps per hour on average. THAT IS A LOT OF POWER. And a LOT of heat. You need very large cables. Especially if you have a long run.
A car battery of only 60 amps isnt going to run that very long. You realy have to think about this.

Cables.
Make sure you buy the right size power cable for your inverter. And go up one size just to be sure if you can afford it. And if you have a long run from battery to inverter make sure you dont get voltage drop that is to severe. Check the voltage at the battery then check the voltage at the inverter to make sure you dont end up supplying to little power and to little amps to your inverter. And always fuse your power connections with something like a MEGA fuse or a decent reset fuse.
Also remember that these power cables when pulling high amps will get hot. cheap cables can have low quality metals that will also increase heat and degrade the voltage and amps to the unit. The lower the resistance the better.

Batteries.
You get what you pay for. We recommend Sealed batteries that are true deep cycle. Not car, 4x4 dual purpose or cheap wet cell batteries. Also , go with a brand name.
Also remember that different batteries have a different rate you can charge them at. Cheap batteries with high internal resistance can get so hot they cook or melt if you charge them to quickly. Filling the compartment with acid smoke and acid water. NOT pretty indeed.
Deep cycle VRLA are the go. Like a Concorde Lifeline or sunextender or a Full river DC series if you want a high quality china VRLA that is a true deep cycle. There is a difference. Just because a battery sais its a 4x4 deep cycle doesnt mean it is a cycling deep cycle designed to do it all the time. A 4x4 battery may only give you 30 to 60 cycles @ 80% discharge where a true cycling battery will give you 300 to 1500 depending on how well you look after it. Initial cost verses constant replacement cost has to be looked at here.
Batteries also self discharge. A wet cell old technology battery similar to 4x4 or car batteries can go flat in 6 months just sitting there. Where a VRLA battery will last 12 months or more.
If you leave your battery flat for more than a few weeks you will do permanent damage. Even if it is only 20% flat.
So make sure you fully charge your batteries every time before storage. And have a shore charger or solar charger to maintain your batteries to a full state of charge. This can double or even tripple the life of your batteries.
So if your about to spend big bucks on batteries. Look after them and buy decent qauality.
remember, if a battery fails. you have NO power. Which means no soup for you. :)

Solar charging systems.
Solar backed up systems are another thing altogether. You should consult your local specialist for this.

BUT saying that you can also use your Victron inverter or inverter charger and chargers with solar charged batteries. Combine your solar charging kit with one of our products for a perfect match.

Marinised V non Marinised.

What is marinised you ask? check out wikipedia. It is very worthy a read and may change your mind about buying a non Marinised inverter.

http://en.wikipedia.org/wiki/Marinised