Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[trikester]

FYI

Last year I car camped for a week in Southern Utah backcountry for hiking and dirt riding. I used a Generac 1600 watt gas inverter type generator to recharge my DS each evening. Putting the inverter type generator on ECO mode let me know when the battery was charged by the rpm's dropping when the load went down.

For my 2013 FX I can use a smaller generator, since the charger only draws 640 watts instead of 960 W. I just ordered the Generac 800 watt inverter generator from Nothern Tool (www.notherntool.com). Right now they are having a sale and the price was $419.99 with free shipping in the lower 48 states. The bigger generator I used for the DS weighed almost 50 pounds, this one weighs 28 lb (shipping weight) and is smaller, so it will be easier to handle.

It was a lot of fun to camp with my electric motorcycle and do daily rides (when I wasn't hiking). I would park the bike about 50 feet from my camp so the quiet generator noise was barely audible. Since my rides weren't long it would typically take a couple of hours to recharge. For the FX, at lower charger power, it will take longer of course. And of course, I had a can of gas, for the generator, in the truck.

Also gave me the "warm fuzzies" to know that if my truck battery ran down, I had a way to recharge it.  I was a long way from another person!

Trikester

[Doctorbass]

Great idea. I hope your generator  efficiency is good

Just pay attention to the wattage, The charger you have is probably having output of 640W.. but the AC input is higher. I guess 725-750W probabaly)

Doc

[protomech]

$420 is a pretty good price for a name-brand 800 watt generator. Honda's 900 watt rated output generator typically runs $800.

Generac says 3.5 hours runtime @ 50% load, probably 2 hours runtime @ 100% load or near enough. Home Depot says 0.28 gal/hour at full load, so just probably 90% load will be around 2 hours.

2 hours of runtime will charge approximately 1.3 kWh into the battery (2.6 kWh/gal).

Zero FX does 71 Wh/mile in city riding, which is probably close to your trail riding consumption trikester as I recall.

2.6 kWh/gal / 71 Wh/mile = 36 mpg.

Then again.. the Honda EU1000i is rated at 3.8 hours runtime on 0.6 gallons @ rated load (900W output). Maybe 4.2 hours charging the Zero (0.14 gal/hour). That gets you 4.5 kWh/gal .. about twice as efficient as the Generac? (64 mpg)

Edit: Northern Tool URL should be http://www.northerntool.com/

[trikester]

So far the Zero ratings for the chargers seems to run closer to the measured input power rather than the output. If they have changed chargers now, then that might have changed but that is why I like the extra margin this generator has. One customer's rating said he ran a 750 watt load on it.

Then again.. the Honda EU1000i is rated at 3.8 hours runtime on 0.6 gallons @ rated load (900W output). Maybe 4.2 hours charging the Zero (0.14 gal/hour). That gets you 4.5 kWh/gal .. about twice as efficient as the Generac? (64 mpg)

I had doubted that the Honda @ 50cc would be so much more efficient than the 38cc Generac. The Honda probably gains some efficiency by being an OHC engine whereas the Generac is OHV. What I'm wondering is if the Generac was running in ECO mode for the 1/2 load running time spec. If not it would have still been running at full rpm even though the load was half. Honda at full load would of course be at max rpm. If both were rated running at max rpm (even though the loads were different) then the running times would be much closer than the specs would indicate. I'll measure the Generac running time when I get it.

The Honda does weigh the same (even though the engine displacement is higher) and is about the same dimensions as the Generac. All of these factors plus cost determined my going with Generac. I have been pleased with the 1600 watt Generac unit I now have and used.

Trikester

[trikester]

RESULTS OF MY EXPERIMENT.

The 850 / 800 watt Generac generator/inverter did not work to power the 650 watt Zero FX charger.

When first connected, the charger draws just a few watts. Then when it turns on it must create a big surge that causes the generator/inverter to fold back. The charger tries a few more times (pulses) to come on and then drops back to the few watts, the Generac comes back up to 120 vac, and the whole cycle starts over again.

The Generac inverter puts out a clean sine wave and the charger, when powered from the AC mains, draws 650 watts and has a 0.99 power factor. So the problem must be caused by a power input surge when the charger first comes up. That surge must be greater than the 850 surge watts the Generac is rated at. I was running the Generac on standard mode, not ECO mode, so it was going "full bore" all the time.

I wasted my money on the 850/800W Generac, I hope this report will prevent someone else from doing likewise.

My 1600W Generac powers the 1000W Zero DS charger very well, so it will also have to be my source for the FX as well. I was trying to save space and weight when car camping with the FX instead of the DS.

Trikester

[protomech]

The chargers are supposed to have a current-limiting pot control behind a rubber stopper. You could probably tweak it to limit the inrush current, at the expense of an otherwise slower charge.

How many watts does the charger draw at the wall normally?

[spelunker]

I wonder if you could tweak the knob down at start, then turn it back up after the charger comes on.

[NoiseBoy]

Just email the manufacturer of the charger, they should come up with a solution for you.  You won't be the only person in the world using their kit with a genset.

[JefRo]

Excessive inrush current is caused by both switching main power supply storage capacitor charging from zero volts and power being applied during a non-zero crossing period in the AC cycle. The latter condition could be easily eliminated with a zero-crossing solid state relay to switch power to the charger. The former condition could be prevented by a soft-start circuit which simply inserts a power resistor in series with the power input which is shorted by a mechanical or solid-state relay after a few seconds of a time out period. I will probably design an inrush current limiter box that can easily plug-in so we can eliminate this problem.

The other condition to consider is over current on a lower power output generator/inverter. A constant current limiting would be required instead of a fold-back type over-current condition. I am not that familiar with generator/inverters so I hope someone can chime in. I am keen to help figure this out since i also want to use the generator/inverter option for rides away from the AC grid.

[trikester]

How many watts does the charger draw at the wall normally?

I listed that.

Excessive inrush current is caused by both switching main power supply storage capacitor charging from zero volts and power being applied during a non-zero crossing period in the AC cycle. The latter condition could be easily eliminated with a zero-crossing solid state relay to switch power to the charger. The former condition could be prevented by a soft-start circuit which simply inserts a power resistor in series with the power input which is shorted by a mechanical or solid-state relay after a few seconds of a time out period. I will probably design an inrush current limiter box that can easily plug-in so we can eliminate this problem.

I'm familiar with this since I used to design switchmode power supplies. Cap inrush would not be the cause because the Generac is already supplying the AC input while the charger is running at a few watts input. 120 VAC is present at the input of the charger, so I assume the caps are charged at this time and then the charger tries to go to full power, that's when the Generac folds back. I also used to design PF corrector circuits (even have a patent for one) and as far as I know they always also limit cap charging current, my PF correction circuits did.

Trikester

[Bakersbread]

So I've been going over all the threads I can find and I am not seeing anything about running a ds on a modified sine wave generator that I can see so far I've been looking at a predator 4000 watt generator from harbor freight. Or a champion 3200 watt from Amazon. Just curious what all of you smart folks have to say about the matter. I'm supposed to go camping this weekend and I've got close to a 300$ budget for some sort of Power device to charge the bike. But I also don't want to damage anything as well. Also I have a chance to buy a Honeywell 2000w generator/inverter that should have a much cleaner sine wave for about the same price but reviews aren't great. Any help would be great

[BSDThw]

You have a DS but which year?

2012 / 2013 and 2014 all have different chargers.

You shouldn't damage your bike with a generator. You can actually use a 100-260V DC source to run the chargers.

The problem is (2013) they use a high inrush current => when it starts up it use an enormous high current peak for ~2 to 10 sine waves.
There are a lot of generators, switching off in this situation.

The 2014 model has a different charger as much as I know, but I don't know what type it is. Maybe the inrush is better? has someone measured this?
 

[Bakersbread]

It's a 2013 high inrush is why I'm looking at the 4000w

[Bakersbread]

Picked up a champion 4000w max 3500 running watt generator for my camping trip this weekend. Charged the bike from about 60% to full and it ran awesome think I could run 2 bikes no problem. Thanks for the input. ended up buying it new in box from someone who had it chilling in their garage for a while for 290$. Thanks again

[hein]

re: using 4000 watts:
With that much excess power, and the generator to lug around already, I'd be tempted to invests in a second charger, to activate once the first one is over its' input rush.
That way if you can charge at twice the speed.
The generator will probably run a little louder, but half as long.
Quite possibly it will run a little more effectively overall with less ( little over half ) the wear & tear.

fwiw,
Hein