By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by CML

Generator power output?

All Topics | Latest Posts

Search for:  in Thread Title in  
Ian Whittaker24/08/2020 22:12:38
65 forum posts
1 photos

Hi,

I'm considering buying a cheap generator for running my two chargers at the field. One is a 80, one a 50W device, although I may soon upgrade and purchase another 80W as I’m using 6 cell packs and they take an age. Would a cheap 700-1000W generator be up to the task? I know it should as far as power output itself goes but would the power output be suitably stabilised with a decent enough ac sine wave for their circuitry?
thanks in advance!

Frank Skilbeck24/08/2020 22:32:21
avatar
4843 forum posts
107 photos

The chargers will be converting the incoming ac power to DC for the charging circuit, most of them have a typical laptop power supply in the case, typically good for 50-60 cycles 110-220v, so they can handle a wide range of power inputs. Running your 3 chargers at max output they are rated for is 210W so even a 700W generator is only running at 30% load so the output should be very stable.

Ian Whittaker25/08/2020 06:28:39
65 forum posts
1 photos

Thanks for that Frank!

flyless25/08/2020 07:28:02
24 forum posts

I bought a Lidl generator great for the price. Only £100 .does the job great at the field

Kim Taylor25/08/2020 09:14:04
322 forum posts
55 photos

Anyone else see the irony in this, or is it just me??wink

Kim

Martian25/08/2020 09:17:56
2604 forum posts
1228 photos

Ditch the IC motor for electric and bring in a IC generator for electric

Cuban825/08/2020 09:49:58
3049 forum posts
1 photos

Trouble with these particular very cheap generators is the noise. At least they are fourstroke and don't stink like the nasty two stroke open frame variety, but in a club environment there might be objections to the noise nuisance.

I needed a 1KW generator for camping and running equipment in my garden and researched very closely the performance of what was on offer with respect to noise. I didn't just go by db levels quoted by manufacturers but listened to generators running at camp sites and at auto-jumbles and markets etc. Without a shadow of doubt the most unobtrusive were the Hondas, but then at eight hundred quid for their smallest one, it's not surprising that they are whisper quiet. No other make that I came across was anywhere close and I'd not be happy to run one (other than a Honda perhaps ) in a club environment to charge batteries if it meant it couldn't be run at least thirty metres from other people and preferably behind an obstruction to muffle the noise further. Different clubs will have differing views - some more sensitive to intrusive noise than others and if one flys alone, then only your own ears to annoy!. Personally, I'd spend the money on a decent quality leisure battery.

I settled on a Machine Mart 1KW unit that I picked up more or less NIB on Ebay for £175 a couple of years back - it's not a bad compromise - noise/price, but I'd not be happy to have it running near the pits in either of my clubs. Noisy petrol models are irritating enough..............

 

 

 

 

Edited By Cuban8 on 25/08/2020 10:08:58

Ian Whittaker25/08/2020 10:32:14
65 forum posts
1 photos

The noise aspect is a very good point actually. There’s a few disused rooms (no windows, doors or even roof left so wouldn’t be a hazard with exhaust fumes) in the area so I’d imagine that may muffle the noise - a long extension would provide the power at a handier location.
I’d considered a decent leisure but the chargers would be pulling upwards of 20A at 12v - the voltage drop at the terminals would be too great (I’ve tried on a new large battery already)!

Dickw25/08/2020 10:43:12
avatar
760 forum posts
102 photos

Another option is solar panels and a smallish battery. A 100watt solar panel plus a 12v 30Ah LiFe battery keeps me going all weekend with several chargers and battery heaters running. Not only silent, but "green energy" as well.

Dick

dsc_0435.jpg

Robert Welford25/08/2020 11:33:17
223 forum posts
4 photos
Posted by Kim Taylor on 25/08/2020 09:14:04:

Anyone else see the irony in this, or is it just me??wink

Kim

Clearly there is the opportunity to "miss out the middle man" ...

Ian Whittaker25/08/2020 12:13:41
65 forum posts
1 photos

Solar panels are an option - in fact there’s one fitted to the roof already that gives up to 10A (by my multimeter) and floats a leisure battery and provides 12v. The snag is it’s very variable - weather and season dependant. If we had decent reliable regular sun 12 months per year I’d happily look at addIng another solar panel and controller...

200-250 watts at 12v is a fair sized current...

Barrie Lever25/08/2020 12:38:15
avatar
342 forum posts
53 photos
Posted by Kim Taylor on 25/08/2020 09:14:04:

Anyone else see the irony in this, or is it just me??wink

Kim

Kim

This is the problem with electric power of most things at the moment, there will be an element of fossil fuel or nuclear power involved somewhere.

Of course the losses involved in running the generator are huge and the emissions every bit as worse as running an IC engine to power the model.

I carried out all of the composite work to fit an electric power system into a boat (full size) for a World speed record attempt (it actually broke the record) this took place in the lake district, there was nowhere lake side that had enough power to charge the Formula E battery, so a huge diesel generator was trucked in to provide the required grunt !!

**LINK**

The same happens at Formula E car races, they have massive banks of diesel generators running to charge the race car batteries - complete and utter madness.

B.

kc25/08/2020 12:51:08
6706 forum posts
173 photos

Whats the point of electric flight if anyone has a generator on the site?

I must remember to propose a new club rule at the AGM ------ generators are banned!

For the cost of a generator you could buy several Leisure batteries instead and no petrol cost!

Dickw25/08/2020 12:55:28
avatar
760 forum posts
102 photos
Posted by Ian Whittaker on 25/08/2020 12:13:41:

Solar panels are an option - in fact there’s one fitted to the roof already that gives up to 10A (by my multimeter) and floats a leisure battery and provides 12v. The snag is it’s very variable - weather and season dependant. If we had decent reliable regular sun 12 months per year I’d happily look at addIng another solar panel and controller...

200-250 watts at 12v is a fair sized current...

That is what the battery is for.

With Solar panels you really need a buffer battery (in my case a 12v 30Ah LiFe) to provide the required current while charging, and the solar panels keep the buffer battery recharged during the periods you are not actually using the chargers.

Charging 2 x 10s 1500mAh packs at 2c at the same time will be drawing about 20 to 25 amps from the buffer battery - see data log of an actual period of use for my solar system. In practice it works just fine even on a dull day.

After one weekends flying I also used it to power my laptop and printer (via an inverter) for distribution of results and certificates on the field.

Dick

20180818 f5b practice day notes.jpg

kc25/08/2020 13:08:17
6706 forum posts
173 photos

Dick - that's really interesting because I didn't think it would be practical. A bit more info about the dimensions and cost of the panel would be useful. Is it practical for a club to have such a setup for multiple users to charge their Lipos?    It would not be secure enough at most club sites to have permanant solar panels, so how easy is it to take along to the field and assemble?

Start a new thread on solar recharging perhaps?

 

Edited By kc on 25/08/2020 13:31:09

Kim Taylor25/08/2020 13:55:58
322 forum posts
55 photos

To add something constructive to the thread this time surprise, our club field has a solar setup incorporated into our shelter - solar panels on the roof (flush, so unobtrusive) feeding to a leisure battery which is buried in a chamber which is covered over with paving slabs. The only easily visible part of the installation is the panel where we plug the chargers in.

I have found that I can charge my 6s batteries at up to 2.5A, although if multiple chargers were in use, 2A is a more realistic current. It takes around 45 minutes to charge a 3000mAh 6s following a 9 - 10 minute flight.

Kim

Edited By Kim Taylor on 25/08/2020 13:56:36

Dickw25/08/2020 14:30:26
avatar
760 forum posts
102 photos
Posted by kc on 25/08/2020 13:08:17:

Dick - that's really interesting because I didn't think it would be practical. A bit more info about the dimensions and cost of the panel would be useful. Is it practical for a club to have such a setup for multiple users to charge their Lipos? It would not be secure enough at most club sites to have permanant solar panels, so how easy is it to take along to the field and assemble?

Start a new thread on solar recharging perhaps?

Edited By kc on 25/08/2020 13:31:09

Well it's not the cheapest option, but yes you can scale it up to supply a club. My own club has 2 x 120 watt panels on the clubhouse roof feeding a bank of 12v batteries in the clubhouse. The system is in constant use and you will often see 4 or 5 chargers connected when members are flying.

My personal system only takes a few minutes to get the panels out of the car and connect up to the battery and solar controller in the car at the start of the day and the reverse in the evening.

These are the panels I use. Not the cheapest, but compact and flexible so good for transportation. There are cheaper versions on ebay. You will also need a solar controller and this one works OK for me. Batteries need to be sized according to likely use so for a club will need to be a substantial capacity.

Dick

Glenn Philbrick25/08/2020 17:05:48
avatar
246 forum posts
73 photos

We also have a series of Solar panels on our container roof. These charge the mower battery and another couple of batteries for club chargers and our weather station. We use a 20ADual Battery controller from e bay that is about £25 this is set to prioritise the mower and then switch to the other batteries. In the summer it well but cannot keep everything topped up in the winter so we have purchased a wind turbine, but have found out now that we need another controller and also a resistance to dump the load when not required. If anybody has any ideas how best to do this it would help.

Thanks

Martin McIntosh25/08/2020 18:05:52
avatar
3572 forum posts
1231 photos

Some time ago I got a brand new Kipor 1kVA for £200. They are four stroke and copies of a Honda. Very good as long as you remember to run them up occasionally to prevent the carb jet from becoming blocked.

Chris Walby25/08/2020 18:28:12
avatar
1345 forum posts
338 photos

Glenn, if you need to dump surplus then why not just heat the container, failing that bury the resistor and just heat the ground.

Could always add a few more batteries to even peaks and troughs out a bit.

PS My vote for another battery/solar panel rather than the all the effort of a generator - do you really fly that much in the winter?

All Topics | Latest Posts

Please login to post a reply.

Latest Forum Posts
Support Our Partners
Slec
Sussex Model Centre
electricwingman 2017
CML
Advertise With Us
Sarik
Latest "For Sale" Ads
NEW POLL - has the pandemic altered your event safety perceptions?
Q: Has the covid pandemic deterred you from attending shows and events in 2021?

 No, I'll be attending just as many as I usually do
 No, but I'll choose my event with greater care
 Yes, I'll attend fewer events going forward
 Yes, I wont attend any where previously I have

Latest Reviews
Digital Back Issues

RCM&E Digital Back Issues

Contact us

Contact us

Magazine Locator

Want the latest issue of RCM&E? Use our magazine locator link to find your nearest stockist!

Find RCM&E!