Belt-driven generators

[janice142]

I'm considering a belt driven generator for Seaweed. Is there any wisdom
from the field regarding same? The new-to-me diesel does not have an
alternator and I'm intrigued by the belt-driven units available. The price
is less than half a Honda or Yamaha 2k which appeals to my purse.

Belt Driven 2900 watt generator head
http://ir-na.amazon-adsystem.com/e/i...1&a=B0000AXDN2
($400)

or
Belt-driven 5500 watt
http://ir-na.amazon-adsystem.com/e/i...1&a=B0000AXDMY
($500)

or for you big guys
10kw belt-driven generator
http://ir-na.amazon-adsystem.com/e/i...1&a=B0000AXDNX
($900)


Side note: Seaweed carries 275 watts of solar at present (with room for two
more 100 watt panels) and I've an Air-Breeze wind gen (latest motherboard)
so for the most part I've got power. Not enough to run the reefer full time
but with the canning I'll do during the engine swap, really a refrigerator
is almost a luxury. Not that I don't like my luxuries!

What's the word from the field regarding the generators shown above? Is
this too good to be true?
Charging to a Xantrex TrueCharge20 (it works/knock on teak) but basically I
don't have anything AC except the Haier refrigerator and until the battery
bank increases (at 450 amp hours currently) I'm not comfortable running the
reefer.

Any current advice from the waterways? (thanks)

[Zach]

Side load on the crankshaft snout is a big deal.

To get the belt tension that is required to transmit that much power, means that the front main bearings get worn to one side.

Most continuous duty mountings, install two identical units one on each side, or mount off a U-Joint that bolts to the crank pulley coming forward, either to the generator its self or a jack shaft that drives the generator.

[transmitterdan]

These generators are not designed to be powered from a propulsion engine. They are AC generators and therefore require precise speed to produce 60Hz power. Modifying a propulsion engine to have precise speed controls would be quite a bit of work.

The insulation rating is class H. That means the insulation can be 180C (350F). The ambient is specified at 40C so they are allowing for a 140C rise in winding temperature. At full load the housing will probably fry eggs (no joke).

Harmonic distortion is pretty common with these types of generators so that should be checked.

Realistically you have to wonder whether these generators will hold up in salt water environments without a significant amount of work. I would not put one in a boat unless some few units demonstrated they were reliable at near full load for 2.5K hours without going up in flames. A couple of smoke detectors mounted nearby and wired to the fuel cutoff would be mandatory.

Then there are those pesky ABYC standards which I won't get into.

Best advice I can give is to run away from this idea before the main engine gets broken or a fire breaks out.

[janice142]

Fixing the links:

2900 watt ($400)
Amazon.com: NorthStar Belt-Driven Generator Head - 2900 Watt: Patio, Lawn & Garden

and
5500 watt ($500)
Amazon.com: NorthStar Belt Driven Generator Head - 5500 Watt: Patio, Lawn & Garden

or 10kw generator for $900
Amazon.com: NorthStar Belt Driven Generator Head - 10,000 Watt: Patio, Lawn & Garden


Just read the posts... well rats. I think my new Volvo if I understood correctly comes with a PTO (Power Transfer O-something) but not if it's going to cook an egg. A smoke detector in the bilge is a good idea ... I can do that. Thanks!

[DeepFrz]

Just read the posts... well rats. I think my new Volvo if I understood correctly comes with a PTO (Power Transfer O-something) but not if it's going to cook an egg. A smoke detector in the bilge is a good idea ... I can do that. Thanks!

The power take off is there to run something like a pump, hydraulic or water, refrigeration compressor, possibly an alternator (much better idea than a generator). Something that doesn't need to be driven at a precise speed.

[janice142]

Originally Posted by DeepFrz

The power take off is there to run something like a pump, hydraulic or water, refrigeration compressor, possibly an alternator (much better idea than a generator). Something that doesn't need to be driven at a precise speed.

Welll shoot. I wish I had a dollar for every good idea that won't work. Thanks DeepFrz. Better to know before $$ than after. I appreciate all the responses.

Back to the thinking board.

[Scott Berg]

Actually it CAN work, just not the way most people think. I have a 10KW Lima 12 pole generator wired for 240/1. It requires rotation at 1800rpm of course. I drive it with four matched belts off of the PTO of our Ford Lehman (it was designed to do that since the boat was first commissioned in 1977). We have a HZ meter @ the helm and a second below to confirm speed before we switch loads it. Motorsailing @ 1600 engine RPM we have 10KW of 240VAC as well as a very nice 7.5-9kts in light airs. Not for everyone but it works very well and gives us a chance to make water while underway in light air without starting the dedicated generator. I have a lot of experience with PTO genets and understand the strengths and weaknesses… this is a great set for us because we have it. If I were starting from scratch I'd install two 250amp 12v Alt's and use an inverter bank to provide 6KW at 120/240 for the added flexibility. Still, if you have a PTO genset and properly configured motor it can be done.

[Cheechako]

Most generators require a specific rpm not the variable rpm of a sailboat auxilary motor.

[a64pilot]

Originally Posted by Cheechako

Most generators require a specific rpm not the variable rpm of a sailboat auxilary motor.

Yes, but it's not that hard really. I have a German Army hand start 4KW generator I use to run my RV, it's 50Hz of course and I have to have a step down transformer to convert 220 to 110, but everything runs just fine on 50hz as opposed to 60hz. Of course if you have ever lived overseas and used you US appliances, your running at 50Hz.
Point being if your between 50 Hz and 60 HZ, your fine, but as you say there is a range of generator RPM you need to stay between, depending on pulleys sourced this may be different engine RPM's, any decent multi-meter will give you Hz.

I don't have that cruising boat myself yet, but I'm looking hard at two serpentine driven high power Alt's as opposed to AC generation myself, still trying to figure out what I'm missing

[janice142]

Still learning... thanks to Scott Berg and others. The theory sounds amazing... yet, this definitely falls into the "might as well" category that can kill a budget faster than most anything.

Thank you gentlemen.