Looking at buying a portable A/C that requires around 1800W+ input according to specs, maybe 10,000-14,000BTU. I wan't to run it off my Honda 3KW genny with a 50M 1.5mm2 extenstion cord. According to voltage drop calc I would see up to 10-12V drop. All I know is these portable gennies output anywhere from 230-240V. So is this kind of drop bad for these A/C units in anyway? Will there be vdrop issues with the high startup/inrush causing either the genny or A/C to not work well?
thanks
Despite common belief AC supply in Australia is actually 230v, not 240. Even then the standard allows for +10% and -6% so the range is actually 216 to 253v and still be within acceptable range.
If your gennie is outputting 230 and you lose 10 due to voltage drop you're still within spec so it should work, at least from the voltage perspective. I'm not a sparky so not confident enough that I can answer the rest of the question correctly.
Despite common belief AC supply in Australia is actually 230v, not 240. Even then the standard allows for +10% and -6% so the range is actually 216 to 253v and still be within acceptable range.
Agreed, Unless you're in WA or QLD, as they are still 240v ;)
https://en.wikipedia.org/wiki/AS/NZS_3112
But 99.99% of these devices are global devices so are rated for use on 220/240v systems, so the OP won't have an issue, ASSUMING the Honda can meet the startup current.
Agreed, Unless you're in WA or QLD, as they are still 240v ;)
Apparently KFC Hot and Spicy needs 240V ;)
Focus on the power calculations, not the voltage. 3KW Generator = 3000 Watts. Load is 1800W. Startup load = (see aircon specs, but estimate +40%). Make sure you use a RCD with the generator.
The inrush current might upset your generator. I don't know much about generators, check the specs I guess?
6x is a handy rule of thumb, so you're looking at about 40-50A at startup. Due to resistive losses in the cable that'll drop you below 200V. This probably doesn't matter to the AC, but it's possible the control circuit drops out and the unit shuts down before it gets a chance to start properly.
Voltage drop wise, 5% is the rule from AS3000.
1800W / 230V = 7.8A
Plug that in here http://www.ipdgroup.com.au/ipdwc/VoltageDrop.aspx and we get 5.57% which exceeds spec, so I have to recommend against it. Should you ignore this advice, the AC will still work, but ensure the cable is fully unwound, not wrapped up in anything that will trap heat, and IN THE SHADE.
If you use a normal household extension cord to do this and leave it in the sun, it will melt, then it will probably catch fire.
Can you not move your generator a bit closer? I mean, running a portable AC of a petrol generator is almost pure insanity to start with, but assuming this is a short term thing I'd be looking to use a 20m cable instead.
Is this for a caravan?
As others have mentioned, this setup is borderline.
You can swing things in your favour by-
If possible, set up the a/c to default to the least power consumption when switched on.
Run the cable in mid air, so that it can cool from all sides and as already
mentioned in the shade.
Note that the cable will be consuming close to 100W. Expect it to get hot.
If the voltage drop is too much you can always buy a voltage stabiliser