Good idea to ask first My immediate answer would make the cable twice the copper size of the one supplied. If you run it up to peak capacity of 600W then it will draw about 50 amps+ or even more if you use extra starting current it will supply(<100A @1200W). So the fuse needs to be bigger than expected use. But the fuse protects the wires from danger so that is important to note, (the inverter will protect itself OK). So the fuse is related to the wire rating.
What will you use it for ? If you just want to use say up to 100-150W or so charging things then OK the supplied wires might work well enough. But sometimes you might plug in a hair drier or an item which might draw a lot more. Then the voltage drop will cause the inverter to trip out or complain by beeping at you as the voltage gets low. Think about usage.
Where will it be mounted ? Near the battery, best, but probably not handy for you to switch on and off and plug into it. Move it to a better place will need need a bigger size of wire if it is far. But you might find it is much handier to use. So how long will the cable run be.( X2 as it has to come and go).
Others may suggest what they did and their useage and comment.
As said above, how long is the cable run & as said X2, if it is 3 metres, it is actually 6 metres + & -
So measure carefully & allow room to manoeuvre at both ends.
4awg cable 6 metres (3m positive & 3m negative) your percentage loss is about 2%. Also do good quality ends so you don't get any resistance where the wire connects to the lug.
A nice thick wire will also act as a heat sink & draw heat away from the connector which is not a bad thing either.
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A nice thick wire will also act as a heat sink & draw heat away from the connector which is not a bad thing either.
EEEK. There should be NO heat at the connector and if there is it means simply that the connector isn't up to the job. Get a connector with much more suitable ratings.
A 50A Anderson plug is NOT suitable for a 1000W inverter. Any fuse / circuit breaker in the system must be rated at the maximum to trip/blow at the rating of the weakest link. eg. If you're using the common 50A Anderson plug and suitable cable then the circiuit breaker / fuse should be rated to have tripped/blown BEFORE 50A is reached. 40A would be a good safe value.
A fuse or circuit breaker is there to protect the wiring and therefore will guard against fire but only IF it is rated correctly.
-- Edited by markf on Wednesday 22nd of April 2020 10:50:00 AM