battery chargers

Honda would be about the same as my 1kva Yamaha inverter gennie. I've had that running 5 fridges and 3 battery chargers and it barely ever got out of eco setting (only when Pesty's bloody great 110 litre waeco or another bloke's 80 litre waeco, cut in). The fridges we were running, all at the same time at xmas 2004, were Waeco 110, 80 & 50 plus Engel 80 and 40. The battery chargers were my 2 x 15amp 3 stage chargers plus another one (6 amps I think).

Hi Rambler,
50 Amps at 12 Volts is still only 600 Watts load not including some losses and inefficiencies in the charger.
So a 10 or 20 Amp charger will be 120 or 240 Watts load on the gennie respectively. (Excluding some small losses and inefficiencies in the charger)

You could theoretically go as high as an 80 Amp charger as well as the Engel on 240 Volts and still come in under the 1000 kva rating of an EU10i.

Geoff

Hi Rambler,

I have run a 30A and 40A 3-stage charger at the same time off of our EU10i. It laboured when both turned on for a couple of minutes but settled down after that.

A general rule of thumb for conversions between AC watts and DC amps is to divide/multiply by 10. This is not an exact conversion however and does not take into consideration startup requirements of some accessories/appliances but is a good enough guide for selecting cable sizes etc for inverters and associated equipment.

Therefore in my situation above it was approximately 800W (both chargers put out more current than claimed - 36A and 43A respectively).

Some other examples:
Powering a 1000 watt AC appliance via an inverter will consume approximately 100 amps DC from a battery.
Charging a battery at 50 amps DC will require approximately 500 watts AC.

Regards
David

I bought a Power Saver 25A 3 stage smart charger. Seems a beauty - I put a fair drain on my starting battery the other day - cranking over the diesel trying to get it running after a fuel issue - was starting to embarrass the battery by the time I had it running. The 3 stager had the battery full as a goog in about 45 minutes I think - an unscientific test of course, but I was surprised how fast it topped it up.
I use the Yam version of your Honda............As I see it (but I'm no tech)......
The Yam (1000W peak/short term, but 900W for continuous running) will run a 25A charger with plenty of capacity to spare.
It seems in rough terms 25A x 12 Volts output on the charger = 300 W draw on the 240 side - 1/3 the capacity (I realise that draw and output are probably not equivalent across that inverter generator).The fridge (probably 5A max) might need another 60W or so.
Seems you could fit a higher capacity charger into the equation or run more camping toys. I chose the 25A charger because it seemed to fit my needs at a reasonable cost. My charger was $350 GST incl. delivered to my door.

Thanks for the replys and I didn't realise it was such a simple conversion--never too old to learn!I will be looking at the different type chargers today and have got a good price of $255 for a 20 amp three stage from an auto elec. friend of mine.That is for a new one called Smart Charge.