power questions

First of all cheers to all of you who posted replies on the oil subject it helped heaps. secondly the 240v convertor in the kombi says 240v at 300w does that mean I cant run the toaster off of it cos that is 650w? but can I still run the 650w toaster and a small tv of the campsite 240v??

The converter is rated at 300W for running equipment from your battery. (no campsite power). If you have an inlet for campsite power you can such as much power as the inlet will allow, using the non converter sockets. The converter is rated to 300W max and is a separate system and should not be overloaded.

mox3772 wrote:the 240v convertor in the kombi says 240v at 300w does that mean I cant run the toaster off of it cos that is 650w? but can I still run the 650w toaster and a small tv of the campsite 240v??

That's what it means all right - you can't plug any 240v device into the converter which consumes more than 300watts (1.25 amps).

At 300 watts your 12v battery would be providing over 25 amps to the converter anyway - that's a very high current flow for a 12v system, and would flatten your battery in maybe 2 hours or so (depending on the Reserve Capacity of the battery). So in reality, the 240 system running off the converter is really a short term convenience thing, so you can run small 240v devices occasionally without being plugged into the mains.

But the 240v you plug into at the caravan site normally uses a 15amp lead (the plugs have a fatter than normal centre prong so you can't use it in a 10amp socket), and the 240v wiring inside the camper is probably rated at 10 amps (2400 watts) so you can run a toaster, a microwave and probably a small hair drier all at once.

In addition to what aussiebug and 59 bus said, most convertors have a couple of ratings like 'Peak' and 'Continuous'. Peak is obviously the most power it can handle for short periods (like a few seconds) and Continuous is the power output it can handle continuously. You need to check what the 300W is referring to. It could be 300W Peak, in which case it is likely that the continuous power output is more like 150W, or it could be 300W continuous, which would mean that the Peak rating is closer to 500-600W.

Electric motors tend to draw more current when they are starting up (ie. getting to operating speed) and then settle down to a nice 'sane' current draw, which is why both ratings are often advertised. 🙂

Modern 12V-240V converters also have an overload protection cutoff. If you try to run something that draws more power than the converter can provide, it will either warn you with beeps, or cut power altogether.

I have a little 100W converter that I bought at Jaycar. It runs my laptop computer with no problems.

The link to Jaycar is:

http://www1.jaycar.com.au/index.asp