Marine Diesel and a strap on generator

[downunder]

Originally Posted by atoll

what you really want is one of these bad boys!
which will produce constant ac and stable freq at variable revs!

Variable speed generator for alternative energy systems

Synchrotek

I think that Discovery Yachts uses something similar for a genset on there 50ft cat from memory rather than a standard genset

i think some army and mambulance vehicles use them to provide AC.

CMD is there provision for PTO drive on your Cummins?

[Tellie]

This set up with such a large generator presents the same problems with home made watermakers with large Cat pumps strapped to the engine. The natural vibration any smaller diesels makes is quickly amplified by a heavy weight set off center of the engine whether you're operating the generator or not. It can shake an engines mounts viciously. If the generator is large enough the low load problems associated with diesels won't be an issue. The horse power needed to turn a charging generator will be sufficient enough to affect the horse power needed for propulsion. But your two 100amp alternators will pick up the slack. Horse power required is also related to the drive system. A dual belt may work, a serpintine belt would probably be better, but horse power required needs to be worked out properly not guessed at to belt a large generator. Also check with your diesels manufacturer as to their opinion on warranty issues by strapping a home designed generator on your engine. I've had people who Yanmar denied any warranty claims because of Cat pumps strapped to their engines for watermakers.

[cat man do]

Originally Posted by downunder

I think that Discovery Yachts uses something similar for a genset on there 50ft cat from memory rather than a standard genset

i think some army and mambulance vehicles use them to provide AC.

Something like this???

The new ENERGO-TEC range of alternators

You have the engine we supply the alternator, (similar size to a standard engine driven 12volt alternator) and "black box" to convert to continuous 220 volt @ 50hz at all rev ranges to provide 4KVA of clean sine wave power supply to power appliances, tools, air conditioners, fridges, safety gear, water makers, to WELD, to charge batteries - for trucks, boats, utilities, military and rural. Installation is bolt on and run, no maintenance, or even replace the existing engine alternator. Power all the time.



ENERGO-TEC 220V POWER SUPPLY

CMD is there provision for PTO drive on your Cummins?

It says yes in the specs

Build Options
The Cummins B3.3 engine have numerous options that make equipment integration easier. Optional features include:

• Cold-start packages, SAE #3 or #4
• Flywheel housings
• Multiple flywheels
• Choice of fan heights, auxiliary pump drive
• Front PTO drive with 100% torque capability
• Gear-driven positive displacement air compressor.

Dont ask me which one it is though, I would have thought looking at this picture that it was the round blank on the right with 2 screws, but I have a pump attached to mine



Looking again perhaps its the one on the left which is obstructed by a belt on my motor.

[Wotname]

Originally Posted by atoll

no problem with running it in the engine room in regards to the marine environment.

pully off the front of the engine is a 16cm diam to a 8 cm on the genset providing 3600 rpm with the engine running @ 1600-1650.rpm
needs twin belts,but never got round to getting a 4th slot madeup off the engine,so it chews the single belt after about 100hrs.

getting the hertz and voltage setting right i have a 2 meters volts and hertz near to the helm on my main house switchboard makes it very easy to set the revs, also a power cut off switch if i need to increase or decreas revs suddenly.

the generator is mounted on a hinged plate next to the engine with a bottle screw to tension,or let the belt slip free if im not using it.

Atoll, you are a man after my own heart - if I had to set something like this for myself, I would the way you did but I had in my mind (perhaps incorrectly) that CMD was looking at start and forget genny setup. Something simple, cheap, small and reliable and I can't see the equipment in the OP doing that. For CMD's sake, I hope I am wrong

[downunder]

From a Discovery 50 brocure - 8kW Auragen

AuraGen FAQ

AuraGen Technology

"A.C. Electrical System

An A.C. panel controls a 30 amp 230v (110voption) ring main, with power sockets in the galley, main salon and cabins. A.C. power is provided by the Victron Energy Quattro 5kW static inverter, or dockside supply. As
an option an 8kW Auragen can be fitted.
The Auragen is a rugged, lightweight, efficient and reliable generator that has successfully been utilised in harsh conditions. A 1kW immersion heater is fitted in each hot water tank for use when using dockside supply.
The Static inverter is powerful enough to power all normal A.C. loads including the optional washer/dryer. If optional airconditioning is required when not connected to shore power, one of the main engines can be fitted with the Auragen and will provide ample power for partial air-conditioning.
So that the engines can be used in replacement of a separate generator, the engine room insulation is enhanced.
This modern solution to A.C. requirements reduces the extra running and service costs of a diesel generator and saves nearly 1/3 ton of weight! However, if you prefer, an optional generator is available if required. We are happy to discuss the merits of either system.
A 3 core double insulated 16 amp PVC dockside power cable (20m) with

appropriate sockets is provided. "

[capngeo]

IMHO, the DC/Inverter route is the only way to go if you want to use your mains for electrical generation

[atoll]

Originally Posted by capngeo

IMHO, the DC/Inverter route is the only way to go if you want to use your mains for electrical generation

when we built the boat,we saved a vast amount of money by having a 240 v built in fridge freezer system,and 240v anchor windlass.

so to raise the anchor not having a genset is not an option.

the cost of fitting a 24v windlass £3500,as oppsed to £500 it cost to build a much more powerful 240 v windlass,and non marine fridge,£500 as opposed to a marine system ~£2000,saving £4500 paid for the generator that we needed anyway!

obviously i would have preferred a 24v system or hydrahlic windlass,but with the genset i am also able to run a big compressor and welding machine ,a victron 70amp charger and a kipont 100amp charger with 2000 ah of batteries.

the back up 3.5kva will also run everything,with the added bonus of having power if we are motorsailing,a great bonus the last 2 trips up the red sea having the airconditioning on when it was touching 50.c outside!

probably not the best option for small boats under 50 ft but on larger yachts that use a lot of power this is the way to go if the main engine is sufficently big enough to run a small a/c genset whilst underway,under power.

sailing trans- equitorial routes generally makes a fair amount of motorsailing unavoidable .

[Dockhead]

Nothing wrong whatsoever with having a giant alternator on one (or both) of your main engines. As you said, you already have two diesel engines on board. And cats are sensitive to weight. I say go for it!

You can buy Leece-Neville schoolbus alternators up to 3 or 4 kW, I think (see: http://www.prestolite.com/literature...ide-lo-res.pdf). You can put in a magnetic clutch so it doesn't run all the time.

You invert the power produced to make 230v AC power.

The bigger it is, the better it will load up your engine. You have to be careful to mount it properly so that it doesn't vibrate too much.

What's not to like? I have a 110 amp 24v Leece-Neville alternator on my boat; was installed as part of the original build of my boat. That's about 2.7kW. I have run all manner of AC equipment, including even my washing machine off it (via a 3kW Victron inverter) and it works perfectly. It charges the batteries excellently. I could probably live without my Kohler generator if I had to.

[cat man do]

Originally Posted by downunder

From a Discovery 50 brocure - 8kW Auragen

Sounds great but OUCH on the price and this was 2002

Got an email from Auragen today.

Price to install one on 6.6L is $6875.00

That's right. I said $6875.00

Can you say ....YIKES!?

For that money I'll buy a new 6.6L diesel w/ Allison and install it in my old truck.

Then take what's left over and play golf in Palm Springs for a week.

With hookers!

Any experiences with Auragen yet? [Archive] - TheDieselPage.com Forums

But then there's this on ebay
AuraGen 5KW Generator System NOS US $1,995.00

[Lagoon4us]

Built a boat years ago and the owner bought a 'Cruise Alternator' you fitted it like any other beltdrive and it put out AC power no matter your RPM.
From memory it had a hydraulic drive unit in it that regulated the RPM both for the AC load and the engine RPM.
Was a great unit...

[Wotname]

Do you have room to mount the genny off the motor?

[Dockhead]

Originally Posted by cat man do

Sounds great but OUCH on the price and this was 2002



But then there's this on ebay
AuraGen 5KW Generator System NOS US $1,995.00

Is there any particular reason why you want to generate AC power directly rather than generate DC power using a bog standard cheap alternator, and invert it with an inverter which you need anyway?

I am agnostic in the AC generator versus DC generator debate, but for an alternator, I don't see any minuses at all to producing DC power. Besides running your AC gear it will run your DC gear and charge your batts. Perfect, flexible, cheap solution.

[cat man do]

Originally Posted by Wotname

Do you have room to mount the genny off the motor?

Should do

[cat man do]

Originally Posted by Dockhead

Is there any particular reason why you want to generate AC power directly rather than generate DC power using a bog standard cheap alternator, and invert it with an inverter which you need anyway?

I dont think so.
I was just under the impression that the alts fitted aren't going to be generating as much as I may need or want, especially if I need to run a/c on those 40deg nights with 95% humidity

[capngeo]

Originally Posted by atoll

when we built the boat,we saved a vast amount of money by having a 240 v built in fridge freezer system,and 240v anchor windlass.

so to raise the anchor not having a genset is not an option.

the cost of fitting a 24v windlass £3500,as oppsed to £500 it cost to build a much more powerful 240 v windlass,and non marine fridge,£500 as opposed to a marine system ~£2000,saving £4500 paid for the generator that we needed anyway!

obviously i would have preferred a 24v system or hydrahlic windlass,but with the genset i am also able to run a big compressor and welding machine ,a victron 70amp charger and a kipont 100amp charger with 2000 ah of batteries.

the back up 3.5kva will also run everything,with the added bonus of having power if we are motorsailing,a great bonus the last 2 trips up the red sea having the airconditioning on when it was touching 50.c outside!

probably not the best option for small boats under 50 ft but on larger yachts that use a lot of power this is the way to go if the main engine is sufficently big enough to run a small a/c genset whilst underway,under power.

sailing trans- equitorial routes generally makes a fair amount of motorsailing unavoidable .

Obviously on a large boat where space and weight is not at issue, a dedicated genset is the way to go. My background on commercial boats got me used to always having AC power at hand; most had at LEAST 2 gennys aboard.

Considering the OP (and probably 95% of the membership) was trying to save space and weight the benefits of generating DC power from the main(s) then converting it to AC via inverter is the way to go. One of the best rigs I saw was a large (I think military surplus) DC aircraft generator, coupled to the engine by a universal joint. Being inline with the crankshaft it did not impose any side load to the propulsion engine. The boat had a large battery bank that took the load when the mains were not running.