I've got a 240ah lithium battery in my camper trailer, I'm thinking of putting in another 240ah battery and upgrading the solar array from 250 watts to 600 watts. Or purchasing a generator/ inverter (around the $500 to$1000 mark). the generator will be the cheaper option, but my concern is the noise. The question is, any recommendations on a quiet generator?
Whenarewethere said
10:34 AM Jul 26, 2025
Build a thick plywood box & fill it with engine bay insulation to cover the generator, with gaps, preferably at the bottom at different ends for air intake & exhaust. The air intake design with internal air flow to keep everything cool.
Plenty of ideas on the internet for air compressors as they are very noisy beasts.
Aging into the night said
12:29 PM Jul 26, 2025
Thanks for the advice on the box, I'll pop into Kings and ask them to start up a 58dcb generator, if its too loud (even with a box), I'll opt for an extra battery and solar panels.
Are We Lost said
01:25 PM Jul 26, 2025
Personally, I would not consider a generator unless there was absolutely no alternative.
Even with excellent sound insulation they are still easily audible. I don't know about other states, but in NSW if you rely on a generator you will be excluded from using it at most National Parks. Also excluded from a lot of caravan parks (non powered sites).
"Generators may disturb wildlife and park visitors and so are generally not permitted in parks. But there are places where you can use them."
If you fit another battery and solar panel, it's done and just works silently in the background. With a generator it is another large heavy piece to lug around, maybe requires a different fuel, need to set up/pack away when camping, and an ongoing cost for fuel and maintenance. Also a theft risk.
Save yourself and your neighbours from the noise pollution of a generator. The restrictions on where you can stay are not applicable.
-- Edited by Are We Lost on Saturday 26th of July 2025 01:43:12 PM
Peter_n_Margaret said
01:39 PM Jul 26, 2025
We have been travelling all over this country for 3 to 8 months each year for 20 years. We almost only free camp and we don't own a generator.
Fit as much solar as you can and you probably won't want or need an extra battery or a generator.
Cheers,
Peter
Aging into the night said
05:55 PM Jul 26, 2025
I do spend a lot of time in N/Ps, usually a lot of shade as well. But I take on board what you say about noise. The only reason I considered a generator was that I ran out of battery power at Wingan Inlet or at least the fridge shut down because there wasn't enough power in the batteries. Headed back a day earlier than planned. Mind you by the time I got to the bitumen the batteries were happy again, hence the query about "quiet" generators. Sounds more and more like there is no such thing. Upgrading the solar and storage may be the way to go.
Peter_n_Margaret said
06:25 PM Jul 26, 2025
If you have lots of money, there is a quiet "generator". We owned one of these in Europe for a couple of years. Makes about the same noise as a compressor fridge, can be installed inside without venting and the exhaust creates a little carbon dioxide and some pure water.
Recently I have been getting popup adverts for motorhome generators by Macfarlane Generators. So I checked their website and here is a link: www.macfarlanegenerators.com.au/products/2187/3kw-usr-petrol-inverter-vehicle-generator-tec30
The capacity of that model probably exceeds your needs. States powered by Honda but maybe other tech for the generator etc.
When I was checking generator prices, for the equivalent capacities, Honda generators were about three times the price as a Kings generator. I cannot comment on the Macfarlane units.
nomadz said
09:31 PM Jul 26, 2025
Hi,
Assuming you only run short of power on rare occasions and that you have a dcdc charger, or your alternator wired to charge your camper batteries, why not use the generator you already have - your vehicle engine.
Ian
Aging into the night said
08:53 AM Jul 27, 2025
Cheers Ian, done that once or twice as have others at various campsites. Something I didn't think about last time I went bush. These days most vehicles are fairly quiet when idling.
erad said
09:29 AM Jul 27, 2025
There is no such thing as a "quiet Generator". Yes - they can be quiet when you tet them in the showroom, but when you get them out in the 'real world' and startusing them, they still make noticeable noise above the background ambient noise level. A quiet generator may put out noise levels of 60 dBa (at 5 m distance). That is good performance noisewise if you are parked near a road, but get away from everyone, and the background noise levels go way lower than that. I worked at a site where machinery noise was a problem. At night, the background noise level was around 30 dBa, and most of that noise was from the cows in the paddock. A 60 dBa generator would then be vey intrusive, even to yourself if no-one else was around.
Aging into the night said
12:43 PM Jul 27, 2025
Yes, I think I may invest in a solar array(600w ish) and another 240 ah lithium battery ( li po4). I'm thinking that those db readings are taken at idle, not under load. Having 2 x 240ah batteries will give me plenty of power to run a fridge and a few lights after fully charging the batteries before leaving home.
Burt65 said
07:51 AM Jul 28, 2025
Aging into the night wrote:
Cheers Ian, done that once or twice as have others at various campsites. Something I didn't think about last time I went bush. These days most vehicles are fairly quiet when idling.
That may be true, but at idle the alternator inn a car is not doing much either...
Peter_n_Margaret said
09:30 AM Jul 28, 2025
Burt65 wrote:
That may be true, but at idle the alternator inn a car is not doing much either...
Is that simply repeated "common knowledge" or have you actually tested it?
I have.
At 1500rpm, my 85A/4.2V alternator charges my 320Ah Li house battery at between 40 and 50A. If I reduce it to 800rpm idle it drops 10A.
Cheers,
Peter
Burt65 said
10:58 AM Jul 28, 2025
Peter_n_Margaret wrote:
Burt65 wrote:
That may be true, but at idle the alternator inn a car is not doing much either...
Is that simply repeated "common knowledge" or have you actually tested it?
I have.
At 1500rpm, my 85A/4.2V alternator charges my 320Ah Li house battery at between 40 and 50A. If I reduce it to 800rpm idle it drops 10A.
Cheers,
Peter
I wouldn't call 1500 rpm an idling speed. However, you can check the voltage of most alternators with a tester to see at which rpm they start to develop the required voltage to actually start to charge a battery..
In my industry, (trucks) most alternator start to give something decent at around 800 rpm but the bulk of the charging start to happen at around 1200 rpm... Car's alternator do work on the same principle, so the only difference would be the actual rpm that in car is normally higher... So yes, I have tested a few thousand alternators in my life, but I haven't any experience on the new "Smart Alternator" that fit most new vehicle these days..
-- Edited by Burt65 on Monday 28th of July 2025 11:00:40 AM
Ineedabiggerboat said
12:22 PM Jul 28, 2025
How do you adjust the idle speed for an extended period?
Burt65 said
01:33 PM Jul 28, 2025
Ineedabiggerboat wrote:
How do you adjust the idle speed for an extended period?
Every vehicle is different... In my current vehicle I use the Cruise Control lever, where I can also adjust the idle at any RPM I wish to use.. Not sure in your vehicle...
Scubadoo said
02:37 PM Jul 28, 2025
Our Mitsubishi Canter 3.9l TD motorhome truck engine normally idles at c750 rpm.
The original alternator is rated at 100A.
According to both our shunt based battery monitors the paralleled 4 cell 300Ah and 4 cell 280Ah LiFePO4 battery packs will charge at 65-70A at 750 rpm or 70-80A at 'fast idle" 1200 rpm until all but full.
1300-3000 rpm makes little if any difference.
No internal battery BMS circuitry.
11 years of full-time travelling and the alternator is still charging the batteries as expected without releasing too much of its smoke reserves despite all the doomsayers.
I'm guessing that the longer cable run associated with caravans and "smart" alternators would produce very different numbers.
Burt65 said
03:25 PM Jul 28, 2025
Scubadoo wrote:
Our Mitsubishi Canter 3.9l TD motorhome truck engine normally idles at c750 rpm. The original alternator is rated at 100A.
According to both our shunt based battery monitors the paralleled 4 cell 300Ah and 4 cell 280Ah LiFePO4 battery packs will charge at 65-70A at 750 rpm or 70-80A at 'fast idle" 1200 rpm until all but full. 1300-3000 rpm makes little if any difference. No internal battery BMS circuitry. 11 years of full-time travelling and the alternator is still charging the batteries as expected without releasing too much of its smoke reserves despite all the doomsayers.
I'm guessing that the longer cable run associated with caravans and "smart" alternators would produce very different numbers.
That's interesting... I just checked with Multispares and the OEM Alternator for your vehicle is rated at 35Amp, not 100. Are you sure that's the OEM alternator? If it is not the OEM, that would explain why it does charge the batteries at 750 rpm. It probably has the wrong size pulley.. (Not wrong for you, but compared to the OEM alternator)..
Scubadoo said
04:05 PM Jul 28, 2025
Burt65 wrote:
That's interesting... I just checked with Multispares and the OEM Alternator for your vehicle is rated at 35Amp, not 100. Are you sure that's the OEM alternator? If it is not the OEM, that would explain why it does charge the batteries at 750 rpm. It probably has the wrong size pulley.. (Not wrong for you, but compared to the OEM alternator)..
35A must be for a 24V system model?
The alternator, pulleys and belts are original and untouched.
I can only assume the FE150E3 Widecab Specsheet for our truck is correct:
"Alternator Capacity 12V-100amp"
Burt65 said
04:35 PM Jul 28, 2025
Scubadoo wrote:
Burt65 wrote:
That's interesting... I just checked with Multispares and the OEM Alternator for your vehicle is rated at 35Amp, not 100. Are you sure that's the OEM alternator? If it is not the OEM, that would explain why it does charge the batteries at 750 rpm. It probably has the wrong size pulley.. (Not wrong for you, but compared to the OEM alternator)..
35A must be for a 24V system model?
The alternator, pulleys and belts are original and untouched.
I can only assume the FE150E3 Widecab Specsheet for our truck is correct:
"Alternator Capacity 12V-100amp"
Yes, that is for the 24 Volts Alternator.. If yours is 12 Volts, then I can see your point... Working on 24 Volts all the times, it does that to you. You start to presume...
I really don't know why, you are getting a full charge at 750 rpm, unless the alternator has been given a particular ratio, for a specific reason, like for people that need the extra power to run the fans on the A/C for the cold room..
In that case you need the alternator to work full time even at low rpm..
The only way for me to achieve that would be to change the pulley on the alternators, or on the harmonic balancer, but than it would work too hard and get too hot at normal driving speeds...
Oh well, it worked well for you, so that's all it matters, really..
Peter_n_Margaret said
06:44 PM Jul 28, 2025
Burt65 wrote:
Peter_n_Margaret wrote:
Burt65 wrote:
That may be true, but at idle the alternator inn a car is not doing much either...
Is that simply repeated "common knowledge" or have you actually tested it?
I have.
At 1500rpm, my 85A/14.2V alternator charges my 320Ah Li house battery at between 40 and 50A. If I reduce it to 800rpm idle it drops 10A.
What I said was it was charging 30-40A at 800rpm which can not be described as "not doing much", and this with just 14.2V. A higher voltage alternator would be better again, even at 800rpm.
It is not a good idea to guess what these things might perform at. Test them and know.
Cheers,
Peter
Burt65 said
07:31 AM Jul 29, 2025
-- Edited by Burt65 on Tuesday 29th of July 2025 07:36:28 AM
-- Edited by Burt65 on Tuesday 29th of July 2025 07:39:55 AM
TimTim said
11:44 PM Jul 29, 2025
Aging into the night wrote:
I do spend a lot of time in N/Ps, usually a lot of shade as well. But I take on board what you say about noise. The only reason I considered a generator was that I ran out of battery power at Wingan Inlet or at least the fridge shut down because there wasn't enough power in the batteries. Headed back a day earlier than planned. Mind you by the time I got to the bitumen the batteries were happy again, hence the query about "quiet" generators. Sounds more and more like there is no such thing. Upgrading the solar and storage may be the way to go.
How many days were you free camping? If you double your battery size then you can camp twice as long in similar conditions but of course in inclement weather things are going to be different. As Peter said, put as much solar on the roof as you can but if you camp in shaded areas you will still have limited output. A portable panel and a good 10m cable will in all probability provide you more power than your 600W on the roof in the shade of trees. I have 780W on the roof but still carry a 200W portable for that reason. In fact you may find that a 200W portable will suffice even without doubling your battery size.
Do you have a shunt on your system to give you an indication of how much power you are using? If you don't you should really get one as LiFePO4 battery voltage is not a good indication of the SOC unless it is fully charged or discharged.
As has been stated, generators are being frowned upon in many places. Stand near one and the noise to you may not seem loud but when someone is 50 metres away siting and enjoying their surroundings they may well perceive the noise differently. At the end of the day only you will know whether a generator is suitable for yourself. Sorry but the only quiet ones that I know are the ones that are not running.
Good luck
Tim
-- Edited by TimTim on Tuesday 29th of July 2025 11:57:32 PM
Aging into the night said
11:22 AM Jul 30, 2025
In full agreement, Tim. I've got an Austrack Telegraph X, it came with a 250w solar panel and 2x 120ah AGM batteries. I've replaced the 2 AGM batteries with an ITECH 240AH LI P04 battery.
I'm going to add another 240ah battery to the system as well as a 600 w solar array. That should see me through a week or so without a lot of sun, sun will be a bonus.
Aging into the night said
11:28 AM Jul 30, 2025
Just to give you an idea of our tolerance for noise levels, we replaced the original water pump with a much quieter Seaflo water pump. Much quieter and less embarrassing.
Whenarewethere said
12:05 PM Jul 30, 2025
We have 3 ARB air compressors built into the car. With the car stuffed full of acoustic insulation, you can hardly hear them.
Brodie Allen said
03:36 PM Aug 2, 2025
Burt65
See you have pirated my proud avatar.
Not welcome!!!
Can't you find something original? that flag has been my mark for many years.
Just so cheap to use somebody elses signature avatar.
B
-- Edited by Brodie Allen on Saturday 2nd of August 2025 04:00:36 PM
Peter_n_Margaret said
04:37 PM Aug 2, 2025
Brodie Allen wrote:
Burt65 See you have pirated my proud avatar.
Not welcome!!!
Can't you find something original? that flag has been my mark for many years.
Just so cheap to use somebody elses signature avatar.
Do you claim that this is your creation and that you own the copyright?
Burt65 probably stole it from the same place you stole it from?
I recall seeing it used on this very forum by others in years past, or was that you changing your user name?
Cheers,
Peter
Dick0 said
09:25 PM Aug 2, 2025
Peter_n_Margaret wrote:
Brodie Allen wrote:
Burt65 See you have pirated my proud avatar.
Not welcome!!!
Can't you find something original? that flag has been my mark for many years.
Just so cheap to use somebody elses signature avatar.
Do you claim that this is your creation and that you own the copyright?
Burt65 probably stole it from the same place you stole it from?
I recall seeing it used on this very forum by others in years past, or was that you changing your user name?
Cheers,
Peter
Why would anyone use an avatar on this Forum that is already in use?
It's not about copyright, it's about being courteous and polite.
Perhaps Brodie Allen could seek guidance from the Webmaster.
I've got a 240ah lithium battery in my camper trailer, I'm thinking of putting in another 240ah battery and upgrading the solar array from 250 watts to 600 watts. Or purchasing a generator/ inverter (around the $500 to$1000 mark). the generator will be the cheaper option, but my concern is the noise. The question is, any recommendations on a quiet generator?
Build a thick plywood box & fill it with engine bay insulation to cover the generator, with gaps, preferably at the bottom at different ends for air intake & exhaust. The air intake design with internal air flow to keep everything cool.
Plenty of ideas on the internet for air compressors as they are very noisy beasts.
Personally, I would not consider a generator unless there was absolutely no alternative.
Even with excellent sound insulation they are still easily audible. I don't know about other states, but in NSW if you rely on a generator you will be excluded from using it at most National Parks. Also excluded from a lot of caravan parks (non powered sites).
Generators not permitted in most NSW National Parks
"Generators may disturb wildlife and park visitors and so are generally not permitted in parks. But there are places where you can use them."
If you fit another battery and solar panel, it's done and just works silently in the background. With a generator it is another large heavy piece to lug around, maybe requires a different fuel, need to set up/pack away when camping, and an ongoing cost for fuel and maintenance. Also a theft risk.
Save yourself and your neighbours from the noise pollution of a generator. The restrictions on where you can stay are not applicable.
-- Edited by Are We Lost on Saturday 26th of July 2025 01:43:12 PM
Fit as much solar as you can and you probably won't want or need an extra battery or a generator.
Cheers,
Peter
If you have lots of money, there is a quiet "generator".
We owned one of these in Europe for a couple of years.
Makes about the same noise as a compressor fridge, can be installed inside without venting and the exhaust creates a little carbon dioxide and some pure water.
EFOY Fuel Cells by SFC Energy - Product overview
Cheers,
Peter
www.macfarlanegenerators.com.au/products/2187/3kw-usr-petrol-inverter-vehicle-generator-tec30
The capacity of that model probably exceeds your needs. States powered by Honda but maybe other tech for the generator etc.
When I was checking generator prices, for the equivalent capacities, Honda generators were about three times the price as a Kings generator. I cannot comment on the Macfarlane units.
Assuming you only run short of power on rare occasions and that you have a dcdc charger, or your alternator wired to charge your camper batteries, why not use the generator you already have - your vehicle engine.
Ian
That may be true, but at idle the alternator inn a car is not doing much either...
Is that simply repeated "common knowledge" or have you actually tested it?
I have.
At 1500rpm, my 85A/4.2V alternator charges my 320Ah Li house battery at between 40 and 50A. If I reduce it to 800rpm idle it drops 10A.
Cheers,
Peter
I wouldn't call 1500 rpm an idling speed. However, you can check the voltage of most alternators with a tester to see at which rpm they start to develop the required voltage to actually start to charge a battery..
In my industry, (trucks) most alternator start to give something decent at around 800 rpm but the bulk of the charging start to happen at around 1200 rpm... Car's alternator do work on the same principle, so the only difference would be the actual rpm that in car is normally higher... So yes, I have tested a few thousand alternators in my life, but I haven't any experience on the new "Smart Alternator" that fit most new vehicle these days..
Here are some easy reading:
https://thepowerfacts.com/what-is-the-minimum-rpm-start-the-alternator-charging/
https://powerclues.com/how-fast-does-an-alternator-have-to-turn-to-produce-power/
https://carsbibles.com/how-many-rpms-to-charge-a-car-battery/
https://www.carsguide.com.au/car-advice/vehicles-fitted-with-a-smart-alternator-in-australia-97156
-- Edited by Burt65 on Monday 28th of July 2025 11:00:40 AM
Every vehicle is different... In my current vehicle I use the Cruise Control lever, where I can also adjust the idle at any RPM I wish to use.. Not sure in your vehicle...
The original alternator is rated at 100A.
According to both our shunt based battery monitors the paralleled 4 cell 300Ah and 4 cell 280Ah LiFePO4 battery packs will charge at 65-70A at 750 rpm or 70-80A at 'fast idle" 1200 rpm until all but full.
1300-3000 rpm makes little if any difference.
No internal battery BMS circuitry.
11 years of full-time travelling and the alternator is still charging the batteries as expected without releasing too much of its smoke reserves despite all the doomsayers.
I'm guessing that the longer cable run associated with caravans and "smart" alternators would produce very different numbers.
That's interesting... I just checked with Multispares and the OEM Alternator for your vehicle is rated at 35Amp, not 100. Are you sure that's the OEM alternator? If it is not the OEM, that would explain why it does charge the batteries at 750 rpm. It probably has the wrong size pulley.. (Not wrong for you, but compared to the OEM alternator)..
35A must be for a 24V system model?
The alternator, pulleys and belts are original and untouched.
I can only assume the FE150E3 Widecab Specsheet for our truck is correct:
"Alternator Capacity 12V-100amp"
Yes, that is for the 24 Volts Alternator.. If yours is 12 Volts, then I can see your point... Working on 24 Volts all the times, it does that to you. You start to presume...
I really don't know why, you are getting a full charge at 750 rpm, unless the alternator has been given a particular ratio, for a specific reason, like for people that need the extra power to run the fans on the A/C for the cold room..
In that case you need the alternator to work full time even at low rpm..
The only way for me to achieve that would be to change the pulley on the alternators, or on the harmonic balancer, but than it would work too hard and get too hot at normal driving speeds...
Oh well, it worked well for you, so that's all it matters, really..
-- Edited by Burt65 on Tuesday 29th of July 2025 07:36:28 AM
-- Edited by Burt65 on Tuesday 29th of July 2025 07:39:55 AM
How many days were you free camping? If you double your battery size then you can camp twice as long in similar conditions but of course in inclement weather things are going to be different. As Peter said, put as much solar on the roof as you can but if you camp in shaded areas you will still have limited output. A portable panel and a good 10m cable will in all probability provide you more power than your 600W on the roof in the shade of trees. I have 780W on the roof but still carry a 200W portable for that reason. In fact you may find that a 200W portable will suffice even without doubling your battery size.
Do you have a shunt on your system to give you an indication of how much power you are using? If you don't you should really get one as LiFePO4 battery voltage is not a good indication of the SOC unless it is fully charged or discharged.
As has been stated, generators are being frowned upon in many places. Stand near one and the noise to you may not seem loud but when someone is 50 metres away siting and enjoying their surroundings they may well perceive the noise differently. At the end of the day only you will know whether a generator is suitable for yourself. Sorry but the only quiet ones that I know are the ones that are not running.
Good luck
Tim
-- Edited by TimTim on Tuesday 29th of July 2025 11:57:32 PM
I'm going to add another 240ah battery to the system as well as a 600 w solar array. That should see me through a week or so without a lot of sun, sun will be a bonus.
We have 3 ARB air compressors built into the car. With the car stuffed full of acoustic insulation, you can hardly hear them.
Burt65
See you have pirated my proud avatar.
Not welcome!!!
Can't you find something original? that flag has been my mark for many years.
Just so cheap to use somebody elses signature avatar.
B
-- Edited by Brodie Allen on Saturday 2nd of August 2025 04:00:36 PM
Do you claim that this is your creation and that you own the copyright?
Burt65 probably stole it from the same place you stole it from?
I recall seeing it used on this very forum by others in years past, or was that you changing your user name?
Cheers,
Peter
Why would anyone use an avatar on this Forum that is already in use?
It's not about copyright, it's about being courteous and polite.
Perhaps Brodie Allen could seek guidance from the Webmaster.