Adding a generator

[mrsmelly]

I have been looking at those small portable 3kva generators (Diesel and Petrol) on eBay. We want one for use with a compact washing machine that we are going to add to the boat. I was going to add a separate supply feed from the generator just to the washer. The idea being to set up the generator on the tow path whilst the weeks washing is done. But then I started thinking about this a bit deeper and I wondered if anyone had ever converted the generator off one of these devices to be mounted in the engine bay and powered by the boat engine whenever needed. That way we could do a wash on the fly whilst moving.

 

I wondered what the issues might be around such a conversion.

 

Regards

 

Mick and Mags.

 

Hi

 

You have loads of replies already. Suffice to say I have an electrolux fitted on my engine and today ( Before I ran out of diesel ) I ran my dishwasher and washing machine whilst cruising including tickover past moored boats and locks and as always it performed faultlessly as it always does. I for one would have nothing else, it also leaves the 12 volt alternators free to charge the batteries rather than power an inverter.

[WotEver]

... I have an electrolux fitted on my engine <snip> I for one would have nothing else, it also leaves the 12 volt alternators free to charge the batteries rather than power an inverter.

But is there really any difference between having an Inverter Generator driven by the engine and having an alternator feeding an inverter?

 

It seems to me that alternator feeding an inverter gives more veratility because you don't have to run the engine if you only need a small amount of 240V power.

 

It's also cheaper.

 

Tony

[mrsmelly]

But is there really any difference between having an Inverter Generator driven by the engine and having an alternator feeding an inverter?

 

It seems to me that alternator feeding an inverter gives more veratility because you don't have to run the engine if you only need a small amount of 240V power.

 

It's also cheaper.

 

Tony

 

The difference is the electrolux does all the work and leaves the 12v alternators to fully charge batteries at same time. If only small amount of 240 needed I just use my invereter....

[Arnot]

I note from a press release I received the other day that Victron are now doing a 10kW Multiplus, and you can parallel up to six of them in single or three phase configuration. So if you want a nice workshop on your floating battery farm you can have a 60kW 3 phase setup.

 

 

Tony

This idea works well on vehicles as well but it takes more than an hour or two to wire up and set up. There's also the small matter of the second mortgage... Still it's quite impressive when you see it in the flesh.

 

Regards

 

Arnot

 

Thanks for the feedback.

 

We have a 1600 watt victron available to provide 230v AC - but a compact washing machine such as the Zanussi 1300 or the Candy would be a bit to much for the device.

 

My reason for using an alternator from a generator tied to the engine was because I have seen a number of them for sale on eBay. One or two have had engine problems but the generator was said to be ok. They come up from time to time and sell for 30-60 pounds for one in the 2.5/3 Kva range.

 

From what I have been able to find elsewhere on the net, it would seem that there are two forms of the portable generator – One is done as direct AC and using a single pole from a three phase alternator, speed is pretty well fixed at around 1500 rpm to create a 50hz output. However, the waveform is not a pure sinewave and can cause problems for electronically controlled devices.

 

The second form is not engine speed dependant and uses a single phase alternator rated between 100 and 120 volts AC output, which is then converted to DC. The waveform and output voltage conversion back to 230v AC are done through an electronic control panel. However, the waveform is a much better approximation to the correct waveform. The engine speed can vary quite a bit. However, at the lower engine speeds current output (Amperes) is somewhat limited.

 

However, I am tempted to go the usual stowed away until needed diesel generator route.

 

But thanks for the replies so far.

It's not really technically feasible to run a synchronous mains alternator from a narrow boat engine, if you gear it so that the voltage and frequency are correct at a reasonable engine speed, when you rev the engine the alternator disintegrates to the point where a lot of the innards would go through a seive. Seen it done!

 

The Travelpower/Electrolux system works but is expensive.

 

I think the best way on a new boat is a combination of proper battery, big alternator and good high power inverter.

 

Regards

 

Arnot

[bag 'o' bones]

For anyone reading this who is has not decided on what engine to use in their new boat it seems that what with the problems in retro fitting a standard engine with 230 volt generating ability, it would make sense to fit a genset engine and run the propeller with an electric motor.

[Robbo]

For anyone reading this who is has not decided on what engine to use in their new boat it seems that what with the problems in retro fitting a standard engine with 230 volt generating ability, it would make sense to fit a genset engine and run the propeller with an electric motor.

 

Q Sara.....

 

Believe they get around 3hrs travelling on batteries alone, with another 3hrs to recharge as well as propelling the boat from the gen.

[nb Innisfree]

Q Sara.....

 

Believe they get around 3hrs travelling on batteries alone, with another 3hrs to recharge as well as propelling the boat from the gen.

 

I think bag 'o' bones's approach is quite a practical solution provided that thoughts of cruising on batteries alone are discounted, maybe a short hop but just treat the genny as a propulsion unit (diesel-electric?) very flexible with the added ability of producing reliable 230v. Still have a domestic bank and inverter for genny off periods.

Edited September 11, 2010 by nb Innisfree

[Robbo]

I think bag 'o' bones's approach is quite a practical solution provided that thoughts of cruising on batteries alone are discounted, maybe a short hop but just treat the genny as a propulsion unit (diesel-electric?) very flexible with the added ability of producing reliable 230v. Still have a domestic bank and inverter for genny off periods.

 

A short hop could be around 5hrs, if you have mooring with electric then this will be cheaper than running the genny. I found this thread which may be of interest.