Install of Kings Inverter

[Stephen.Coff]

G'day Guys,
Anyone used the Kings 1500w Inverter?
https://www.4wdsupacentre.com.au/advent ... erter.html

Feedback?
Anyone have any cable size advice for mains feed to inverter if approx 7m long. Note: Twin positive & negative feed.

[HK1837]

1500W assuming decent efficiency is at least 125A at 12V. I haven't got AS/NZS3008.1.1 in front of me but I'd be using at least 35sqmm flexible on that (assuming a single pair of wires not two pair), as much for the current carrying capacity as the voltage drop at full load. I'd also put a decent 12V power switch on it right at the battery as you don't really want to run cable that size 7m unprotected through a car with it always energised, this sort of thing:
https://www.ebay.com.au/itm/Battery-Iso ... :rk:1:pf:0

You could also use parallel 16sqmm and get away with it. Unfortunately no picture here but this is the stuff I mean:
http://www.bambachcables.com.au/product ... pper-cable

Or a bit more automated using a 12V contactor with a switch back at your Inverter, this sort of thing:

https://www.ebay.com.au/itm/12V-200A-St ... rk:14:pf:0

The other way is a 150A fuse back at the battery, like this sort of thing: https://www.ebay.com.au/itm/PROJECTA-10 ... rk:25:pf:0


Probably the better way to do it is put the aux battery back at the Inverter and run really short wiring to the Inverter, with a dual battery setup and a smaller cable to the front for charging purposes.

[Stephen.Coff]

1500W assuming decent efficiency is at least 125A at 12V. I haven't got AS/NZS3008.1.1 in front of me but I'd be using at least 35sqmm flexible on that (assuming a single pair of wires not two pair), as much for the current carrying capacity as the voltage drop at full load. I'd also put a decent 12V power switch on it right at the battery as you don't really want to run cable that size 7m unprotected through a car with it always energised, this sort of thing:
https://www.ebay.com.au/itm/Battery-Iso ... :rk:1:pf:0

You could also use parallel 16sqmm and get away with it. Unfortunately no picture here but this is the stuff I mean:
http://www.bambachcables.com.au/product ... pper-cable

Or a bit more automated using a 12V contactor with a switch back at your Inverter, this sort of thing:

https://www.ebay.com.au/itm/12V-200A-St ... rk:14:pf:0

The other way is a 150A fuse back at the battery, like this sort of thing: https://www.ebay.com.au/itm/PROJECTA-10 ... rk:25:pf:0


Probably the better way to do it is put the aux battery back at the Inverter and run really short wiring to the Inverter, with a dual battery setup and a smaller cable to the front for charging purposes.

Legend, thanks for the reply HK1837.

So if understanding correctly, easiest to mount inverter in rear with spare battery & very short cable.
Switch inverter via say a 200-250amp contact relay complete with 150amp inline fuse.
Only run small thin cable from battery to aux battery to trickle charge.
I'll look up the noted code to see if i can confirm cable size for say 150amps.

If the above is correct then, question.
Q. What amps should I expect to charge the Aux battery and hence size that cable?

[fracturedranga]

That will depend on what type of battery charger you plan to use

[HK1837]

1500W assuming decent efficiency is at least 125A at 12V. I haven't got AS/NZS3008.1.1 in front of me but I'd be using at least 35sqmm flexible on that (assuming a single pair of wires not two pair), as much for the current carrying capacity as the voltage drop at full load. I'd also put a decent 12V power switch on it right at the battery as you don't really want to run cable that size 7m unprotected through a car with it always energised, this sort of thing:
https://www.ebay.com.au/itm/Battery-Iso ... :rk:1:pf:0

You could also use parallel 16sqmm and get away with it. Unfortunately no picture here but this is the stuff I mean:
http://www.bambachcables.com.au/product ... pper-cable

Or a bit more automated using a 12V contactor with a switch back at your Inverter, this sort of thing:

https://www.ebay.com.au/itm/12V-200A-St ... rk:14:pf:0

The other way is a 150A fuse back at the battery, like this sort of thing: https://www.ebay.com.au/itm/PROJECTA-10 ... rk:25:pf:0


Probably the better way to do it is put the aux battery back at the Inverter and run really short wiring to the Inverter, with a dual battery setup and a smaller cable to the front for charging purposes.

Legend, thanks for the reply HK1837.

So if understanding correctly, easiest to mount inverter in rear with spare battery & very short cable.
Switch inverter via say a 200-250amp contact relay complete with 150amp inline fuse.
Only run small thin cable from battery to aux battery to trickle charge.
I'll look up the noted code to see if i can confirm cable size for say 150amps.

If the above is correct then, question.
Q. What amps should I expect to charge the Aux battery and hence size that cable?

What I meant was the best way would be to put the battery back at the inverter for a large inverter like that and run short cables. The risk of an issue with the cable is a lot lower the, but as it is a cheap (Chinese) inverter I'd still be worried about it's smoke containment so at least put a fuse on it. A solenoid or switch or quick disconnect terminal wouldn't hurt so it is only powered when you need it to be.

Not a small, thin cable to charge from the alternator, but not quite as big as what you need to run the inverter. This assumes it will only run when the engine is off. If you run it with the engine running then the alternator will try and power the inverter, plus the start battery will also try and supply some power if they are paralleled. This is why I suggested a good dual battery controller, even then you still need a decent cable between the batteries.

AS/NZS3008.1.1 can be hard to read, and the data given is for 50Hz. DC is a higher rating. I will look today if I get a chance.

[HK1837]

I just checked, as far as current carrying is concerned (125A) I'd stick with 35sqmm. You may get away with 25sqmm in non-PVC insulation (like rubber or EPR) especially if you are putting the inverter right next to the battery. PVC will be rated V75 or V90 or something like that. Try and buy it as a double insulated figure 8 (like a big speaker cable), or if not use a double insulated welding cable, although if you are right near the battery single insulated will be fine.

Here is a voltage drop example for you. Again this is for 50Hz (ac) but close enough for the purposes of illustration:

35sq mm single core has a resistance of 0.638 Ohms per kM when the cable is at 75deg C (it will get this hot pulling 125A). So for 7m this equates to 0.638/1000 x 7 = 0.0045 Ohms.

Voltage drop across the cable will be V = R x I = 0.0045 x 125 = 0.56 Volts. So the Inverter gets about 0.6V less, so draws more current etc. This shows you why you are better off with the battery close to the big power consumer. The flip side of this is of course the charge voltage from the alternator is compromised also by voltage drop, which can only be alleviated by running a decent supply cable from the starting battery to the aux battery, via a dual battery controller. Some people will run a dc-dc converter too to up the voltage a bit to compensate but that starts to get expensive too.