Any further updates will be posted on the link above.
Thursday, 21 November 2013
Generator Project New Blog
As the generator has become a minor project of its own I have created a new blog to cover it.
Wednesday, 16 October 2013
Generator Update
The new drive plate has been made and fitted.
Once the drive plate and new support frame was fully bolted into place a final dial gauge test was done. On the end of the shaft there was 5/1000th of an inch runout. This shaft will be cut back on final assembly to about 11/4" (30mm) when the HRC90 coupling is fitted. This will reduce the runout even more. The coupling is designed to take way more runout than this.
This video explains better than I ever could how the taper lock system works.
Saturday, 5 October 2013
New Genset Frame
This is the new frame I have made to do 2 jobs. 1st job is to support the rear of the engine. Previously the 230v alternator body did this. The new 12v alternator isn't designed to do this
This doesn't look much but it took several hours of head scratching and trying different things. There was 2 main problems / considerations in the design. The 1st and most important was the maintain all the original parts so it could be put back to original. 2nd, I wanted it all to fit back in the original sound reducing box. The other minor problems were to ensure access and use all the original bolts and the exhaust pipe route got in the way. The final consideration was to ensure the new alternator could be fitted and removed as the pad mount lugs are wider than the diameter.
The pads of the alternator will sit flat on spacers on top of the flats of the bottom angle irons and bolted through
This doesn't look much but it took several hours of head scratching and trying different things. There was 2 main problems / considerations in the design. The 1st and most important was the maintain all the original parts so it could be put back to original. 2nd, I wanted it all to fit back in the original sound reducing box. The other minor problems were to ensure access and use all the original bolts and the exhaust pipe route got in the way. The final consideration was to ensure the new alternator could be fitted and removed as the pad mount lugs are wider than the diameter.
The pads of the alternator will sit flat on spacers on top of the flats of the bottom angle irons and bolted through
Friday, 4 October 2013
HP Calculations
In reply to a comment here, I realised I hadn't shown my workings!
So is the 12hp engine powerful enough?
This is the horsepower required to achieve this.
This is what I am looking to achieve at 1500rpm
This is the horsepower required.
These calculations are of course in ideal situations with a new engine, however there is still about 33% to play with.
So time will tell, but I'm confident the engine will drive it. Interestingly when I was considering a 1500rpm 4 pole 230v alternator it was calculated by the intended supplier that it could not exceed 3kw output.
So is the 12hp engine powerful enough?
This would be the maximum output. It's very unlikely my batteries could ever draw this much. The plan is to run the engine at 1500rpm, however it can be run faster if needed. Why 1500? well its very quiet at that rpm, but even at 2000rpm its a fraction of the noise at 3000rpm.
This is the horsepower required to achieve this.
This is what I am looking to achieve at 1500rpm
This is the horsepower required.
These calculations are of course in ideal situations with a new engine, however there is still about 33% to play with.
So time will tell, but I'm confident the engine will drive it. Interestingly when I was considering a 1500rpm 4 pole 230v alternator it was calculated by the intended supplier that it could not exceed 3kw output.
Wednesday, 2 October 2013
US Alternator Has Arrived
The Ecoair alternator arrived today from America :-)
Just a picture quick entry this time.
Just a picture quick entry this time.
Its big! and it's heavy 18kg!
In the interim I have been looking at drive options. I have decided to make a new drive plate:-
to which I will probably use a Fenner HRC Coupling or possibly a Fenner Tyre Coupling.
Old drive plate
Wednesday, 18 September 2013
12DC Generator
I am sick and tired of my current 230v genset causing all sorts of problems with unstable voltage, poor quality sine wave and noise, (engine not electrical) although I suppose there is plenty of that too. My Victron doesn't like it and I have killed so many switch mode power supplies for mobile phones, iPads, even the power supplies in a Sky box, a DAB radio and a NiMH drill charger which actually caught fire didn't like it.
So why have I or indeed any boaters got a generator? I think in most cases 99% + its to charge our batteries. Of course we all have one bolted to the side of our main engine which by and large does an excellent job of charging the start battery for which it was designed for and a pretty fair to poor job of charging supplementary or house batteries via various methods of diverting surplus charge elsewhere.
When I did my alternator conversion the one thing I didn't expect to be as successful as it has proved was the ability to run my oven 2.2kw through the inverter and still be putting in as required depending on the SOC of the batteries up to 60amps of charge. This set me thinking, why the hell am I making 230v to run my inverter charger to then charge the batteries at a maximum of 120amps when my new alternator on the main engine I have seen putting in over 180amps without conversion losses. I have read somewhere that the Victron inverter on charge makes 800w of heat as well. Heat I really don't want. This I can well believe as I had to add additional fans to the inverter space under the stern steps in order to keep it cool enough to keep the charge rate up as it shuts down the charge rate according to the running temperature.
So you might wonder where this is leading. Well as I see it its simple. Use my current 500cc genset engine to spin a 12v alternator instead of running a 4000cc (4L) to do the same. Big engines like this suffer from bore glazing running on tickover or low loads. Google bore glazing its an interesting topic with many views generally eventually agreeing its not a good thing.
My initial research lead me to a 220amp automotive alternator
but this would need spinning at 5000+rpm so gearing would be required. I had considered running a 3kw 230v alternator at 1500rpm (4 pole) but again this still had the electrical conversion losses but in preparation for this I managed to con my current genset into running at 1500rpm by removing a slow run cutout relay. At 1500rpm its as quiet as a sewing machine. But then I will need to have made for me a drive pulley set and this will have additional frictional losses and belt slip reducing the limited power the genset engine has.
So having bought the 220amp automotive unit
I did some more Googling and found a slow speed 12v alternator from the USA.
The Ecoair company make probably exactly what I and every boat owner needs, and a 24v version also.
After exhaustive discussions with one of the directors I have purchased one of the 12v (14v) units with the option of becoming the UK / EU importer distributor.
So having stripped my current genset:-
So why have I or indeed any boaters got a generator? I think in most cases 99% + its to charge our batteries. Of course we all have one bolted to the side of our main engine which by and large does an excellent job of charging the start battery for which it was designed for and a pretty fair to poor job of charging supplementary or house batteries via various methods of diverting surplus charge elsewhere.
When I did my alternator conversion the one thing I didn't expect to be as successful as it has proved was the ability to run my oven 2.2kw through the inverter and still be putting in as required depending on the SOC of the batteries up to 60amps of charge. This set me thinking, why the hell am I making 230v to run my inverter charger to then charge the batteries at a maximum of 120amps when my new alternator on the main engine I have seen putting in over 180amps without conversion losses. I have read somewhere that the Victron inverter on charge makes 800w of heat as well. Heat I really don't want. This I can well believe as I had to add additional fans to the inverter space under the stern steps in order to keep it cool enough to keep the charge rate up as it shuts down the charge rate according to the running temperature.
So you might wonder where this is leading. Well as I see it its simple. Use my current 500cc genset engine to spin a 12v alternator instead of running a 4000cc (4L) to do the same. Big engines like this suffer from bore glazing running on tickover or low loads. Google bore glazing its an interesting topic with many views generally eventually agreeing its not a good thing.
My initial research lead me to a 220amp automotive alternator
but this would need spinning at 5000+rpm so gearing would be required. I had considered running a 3kw 230v alternator at 1500rpm (4 pole) but again this still had the electrical conversion losses but in preparation for this I managed to con my current genset into running at 1500rpm by removing a slow run cutout relay. At 1500rpm its as quiet as a sewing machine. But then I will need to have made for me a drive pulley set and this will have additional frictional losses and belt slip reducing the limited power the genset engine has.
So having bought the 220amp automotive unit
220amp Automotive alternator
I did some more Googling and found a slow speed 12v alternator from the USA.
The Ecoair company make probably exactly what I and every boat owner needs, and a 24v version also.
325amp Slow spin alternator
So having stripped my current genset:-
Vetus genset with cocoon
The 230v armature still to be removed
Armature and coupling removed
Flywheel end of the engine
This seems to be a 6 hole fixing with 200mm PCD so I will need to look up the SAE of this fixing.
This is an ongoing project so I might start a separate blog on this conversion. In the meantime if you want to follow it make sure to bookmark it of check back regularly
Friday, 16 August 2013
Making Keel Cooling For A Friend
A very good friend of mine had a new engine fitted recently. The boat was an ex hire boat and only had a 35hp engine which is fairly normal for a hire fleet boat. The hire companies do this deliberately as they want to control the speed the boat can achieve and they probably govern the engine as well.
The beauty of these boats is they can be bought for very reasonable price, they come well equipped with quality fittings to stand the riggers of hire and the hulls are well built.
So the internal skin tank was set up for a 35hp engine, a fact the professional boat company installing the new 52hp engine somehow overlooked? Hmm?! IMO the first thing to work out when fitting an engine is how to cool it. If you can't cool it you can't run it. Well you can but so long as you don't call up all the horses or want to destroy it.
The problem only manifested itself when Sue needed to punch against the flow on the Thames, which of course needed more horses than poodling on a canal which she had been doing since the new install.
There were 2 options to solve this, another internal skin tank linked to the original which would require the engine bay to be cleared of things like the errr! engine! The other option an external skin tank, or keel cooling which is really what a skin tank is requiring just 2 holes made and welded in the hull. No engine removal and just a few hours work in a dry dock.
There's a well regarded formula for working out the cooling area / engine hp. It's HP divided by 4, so a 52hp engine needs 13sq/ft of surface area. The most compact way of doing this is with tube, in this case 80 x 40 box section which gives 1sq/ft of surface area every 16" of length. To further compact this a serpentine patten is the norm.
This is it.
So this is what I came up with and made for Sue & Vic. See the links below as she takes up the story on her blog. Read backwards from here:- Sadly I wasn't able to fit it for her, but the local floating dry dock did a great job.
If you like boating blogs, you will love Sue's. Her's is constantly ranked in the top 10 UK boating blogs, its has a great balance of travelogue, opinion, and lifestyle showing the good and not shy of speaking about the not so good. Always punctuated with great photos and on the sidebars masses of excellent links, tutorials and resources as well as a massive list of fellow boater blogs.
The beauty of these boats is they can be bought for very reasonable price, they come well equipped with quality fittings to stand the riggers of hire and the hulls are well built.
So the internal skin tank was set up for a 35hp engine, a fact the professional boat company installing the new 52hp engine somehow overlooked? Hmm?! IMO the first thing to work out when fitting an engine is how to cool it. If you can't cool it you can't run it. Well you can but so long as you don't call up all the horses or want to destroy it.
The problem only manifested itself when Sue needed to punch against the flow on the Thames, which of course needed more horses than poodling on a canal which she had been doing since the new install.
There were 2 options to solve this, another internal skin tank linked to the original which would require the engine bay to be cleared of things like the errr! engine! The other option an external skin tank, or keel cooling which is really what a skin tank is requiring just 2 holes made and welded in the hull. No engine removal and just a few hours work in a dry dock.
There's a well regarded formula for working out the cooling area / engine hp. It's HP divided by 4, so a 52hp engine needs 13sq/ft of surface area. The most compact way of doing this is with tube, in this case 80 x 40 box section which gives 1sq/ft of surface area every 16" of length. To further compact this a serpentine patten is the norm.
This is it.
So this is what I came up with and made for Sue & Vic. See the links below as she takes up the story on her blog. Read backwards from here:- Sadly I wasn't able to fit it for her, but the local floating dry dock did a great job.
If you like boating blogs, you will love Sue's. Her's is constantly ranked in the top 10 UK boating blogs, its has a great balance of travelogue, opinion, and lifestyle showing the good and not shy of speaking about the not so good. Always punctuated with great photos and on the sidebars masses of excellent links, tutorials and resources as well as a massive list of fellow boater blogs.
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