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Cat Gensets

Discussion in 'Generators' started by NEO56, Jun 11, 2014.

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  1. NEO56

    NEO56 Member

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    I was talking with my Rep the other day, and he told my of one of his customers who insisted on installing Cat Gen Sets on his boat along with the Mains. He told me that they, while being more expensive, are bullet proof and run forever. I kinda had my heart set on Northern Lights generators, thinking they were the cats (no pun intended) meow. Could I please get some feedback on this?

    Thanks.
  2. Garry Hartshorn

    Garry Hartshorn Senior Member

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    It has been quite while since I worked on a boat with Cat gensets but they seemed like a heavier duty machine compared to Northern Lights. I would seriously consider them on a new build especially if installing Cat mains.
  3. K1W1

    K1W1 Senior Member

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    Hi,

    It will depend very much on which CAT engine drives it.

    Some of the smaller ones have a very poor reputation while the bigger ones are bulletproof
  4. captholli

    captholli Senior Member

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    I was involved in a total repower of a 50 meter Benetti in 2011 for the Mains and Gens and Cat didn't have a lot to offer in the 60 to 90 KW range. The 4.4 Acert is a Perkins engine painted Cat Yellow swinging a Stamford alternator with Woodward controls BUT at a price point of $35,000 for a 80 KW with sound enclosure that's a hard deal for most owners / Captains to pass up compared to the same Northern lights 6 cyl. 86 KW @ $ 140,000. The owner went with the 4.4's & they were replaced within two years with less than 3,000 hours on them. Rear seals let loose twice on both units, ECM problems , speed sensors to name a few. The C-9 that I've had aboard vessels as generators are notorious for their HEUI pump failures and ECM problems. The C9 as a main engine would make more sense but they didn't fare well as generators. I don't know what size vessel that your building but unless your looking @ 150 KW and up then Cat hasn't much to offer and for that matter Kohler has more than their fare share of troubles as they were standard spec. equipment on Christensen yachts as I was the build Engineer on Hull 034 "Odessa" and the boat has had nothing but problems with all three Kohler's one 125 KW and two 90KW units to the point that I believe several of the new Christensen hulls are calling for the Cat C- 6.6 unit and I'm not familiar with this engine and haven't been involved with it in the field. Any feed back on this 6.6 K1W1? Hopefully it will be a good machine as I like the Cat engines for Main propulsion 3500 series & customer support network.
  5. K1W1

    K1W1 Senior Member

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    Yes, I posted it earlier

  6. NEO56

    NEO56 Member

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    captholli, it's a 105 ft. (95 w/10 ft. cockpit) semi displacement hull with a 24 ft. beam.
  7. Capt J

    Capt J Senior Member

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    I would go Northern Lights in your application based on the info given above and the fact that Northern Lights has been producing solid generators in your size range for decades upon decades and mostly for commercial fishing boats that need reliability and such.
  8. captholli

    captholli Senior Member

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    As of 6 months ago the lead time for a N.L. 85 KW gen was eight months so what ever you do have the builder figure out the load calculations for KW rating and I also recommend taking the interior designers lighting choices into account as a few builders have made their calculations only to then have a "inferior desecrator" come in with a crazy lighting plan and kill it. LED is the way to go these days. No more of fifteen different bulb sizes and wattage to deal with.
  9. NEO56

    NEO56 Member

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    I told my rep that I wanted calculations for everything including underwater lights, plus any compressor spikes, washer/ dryer (s) all running at the same time, anything that draws power to be included in number, and then add 20%. He concurred saying that no Owner has ever regretted going to bigger gen sets. Most Owners skimp on the power side and live to regret it. And I agree that LED is the way to go. She's going to be a nice looking boat on the exterior, but a commercial work boat below decks, with built in redundancy where ever possible.

    Thank you all for you help and advice!
  10. K1W1

    K1W1 Senior Member

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    Hi,

    Does your "rep" actually have some operational yachting experience?

    That is a very misleading statement

    There have been many yachts over the years where the gensets were grossly oversized and they needed load banks to keep them running without making a mess everywhere and glazing bores.
  11. captholli

    captholli Senior Member

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    Oversizing a generator by 20 percent is not the way forward here. if in fact your going with a PMS onboard it would-be better to be right on the line @ 90 percent maximum operational load and 75 -80 percent normal load and let your PMS bring the second gen on the buss until the load drops. This is pretty hard for a lot of builders to get right so either they throw load banks aboard or always seem to undersize one gen and oversize the second gen. Of course the night time load is going to be the lightest and at that point your not going to have the proper loading for the engine without load banks. loading a yachts generator for optimum engine performance at all times of the 24 hour clock is difficult. I've been following Marmots posts for his proprietary systems that Deangelo is now using and don't know if it could somehow be scaled to be used as a sort of smaller load bank with the effective burning of your exhaust.
  12. NEO56

    NEO56 Member

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    He seems to....claims he's owned several diesel boats, and currently has one tied up behind his house, a 64' I know that's true he's sent me photo's.
  13. NEO56

    NEO56 Member

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    O.K. while we're on the subject, two different sizes for gen sets? One big main and a smaller one as a night or light load gen. That really doesn't sit right with me...if the large gen goes down, then I've got problems. I'd prefer to have the second gen be able to take over. Is my thinking flawed? At what point on the power curve will the engine start to lug? 30%? 50%?
  14. K1W1

    K1W1 Senior Member

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    Hi,

    A classed genset should do 110% of rated load.
  15. K1W1

    K1W1 Senior Member

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    Hi,

    I hope you are having a joke here and have not entrusted this project to someone who you have no verifiable history of and have accepted e mailed photos as a proof of one of his claims.
  16. captholli

    captholli Senior Member

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    Sorry, I wasn't to clear on that. I have to be careful here, A few builders will perform a load analysis and come up with an estimated KW load factor and install the #1 gen to that factor then over size gen #2 to take up any miscalculations brought up earlier such as lighting or customer change orders that might require more KW from the already selected and installed machinery.
    If you select two identical units with PMS than you can use the load shedding option the PMS gives you by auto dropping the non critical loads such as boilers, half the AC compressors, the hot tub etc before it automatically parallels the second gen. It is better to have your PMS auto parallel as some of the equipment dropped on non pref will have to be reset, things like freq.. Drives or motor starter circuits. Get a verifiable expert in this field if it's early enough to still do so.
  17. Old Phart

    Old Phart Senior Member

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    I dunno
    True, as in, it is his; or true, as in, a boat is tied up behind his house?
  18. Capt Bill11

    Capt Bill11 Senior Member

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    +1 to all that. And I can't see the point in adding 20% to the max load calculations.
  19. Capt Bill11

    Capt Bill11 Senior Member

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    Well then, he must be a expert on Genset selection then. ;-)
  20. dsharp

    dsharp Senior Member

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    Some boats are set up with a smaller "back-up" generator. It just depends on weight, available room and costs to run and maintain. Noise can also come into play, especially at night. You can't always have everything you want on a boat. Well you can, I guess but, sometimes they roll over. If you are going to have many water toys you may want to stretch that cockpit.