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Inverter questions

Posted: Sun Aug 03, 2008 12:18 pm
by stockhorse
OK got a whole lot of hypothetical and what if's for discussion.

If you fit a 2000w peak 1000w continuos inverter but you only want to ever draw a max of 300w continuos, would this be logical or would it be more practicle to just fit a 600w peak 300w continuos inverter.
The thinking behind this is the larger inverter is cheaper and would never run near peak so would last longer. False logic?

If a 2000w peak 1000w continuos is fitted then at max draw it would draw 166.6 amps so a 175 amp anderson plug should do the job but what type and size fuse would you use?

Since there will be 240 volt power in the vehicle and although the inverter has overheat and overload cut off protection,what extra safety devices would you use? (i.e. a fused powerboard between inverter and appliances)


Thanks for the opinions.

Posted: Sun Aug 03, 2008 1:36 pm
by drivesafe
Hi stockhorse, an inverter requires so much power just to maintain itself, before you get anything on the 240 vac output.

The amount of power required will vary based on the size of the inverter and the amount of 240 vac being produced.

It’s a safe bet that a small inverter would be more efficient for the amount of power you need.

As to the size of the inverter, as a rule of thumb, it is always safer to pick an inverter with a continuos output of at least 50% more than what you will need.

This protects the inverter from being at maximum load all the time plus the fact that many inverters start to charge the AC wave output as the load approaches the inverters maximum, which not good for your 240 AC electrical gear.

So a 450w inverter and 50 amp Anderson plugs connected to at least 6B&S ( 13.5mm2 ) cable to minimise voltage drop.

Cheers.

Posted: Sun Aug 03, 2008 7:34 pm
by ausoops
on our trucks at work we run 2400W inverters and manage to kill the truck batteries probably every 4-6 months per truck. we run 4 batteries in series/parallel. if you are using one on a single battery you will kill it quick unless you run the car for ages afterwards or charge it overnight at home.

fuse wise i would use a 200A fusible link and 35mm2 cable as a minimum.