Generator capacity in real-world use

jfm said:
your maths is out
Click to expand...

:) thought so, and you are indeed right, the house batteries are 4 x 120ah for 240ah 24 V total before any loss.

Thanks both for your input and clearing that up, genset for a/c will be the MO.

It was your Sq78 build thread, JFM, that inspired me regarding running a/c off batteries anyway.

Genset is in lazarette with the steering gear and passerelle - not the engine room, and anyway given our intended use of day trips mainly with only the occasional overnight, I doubt it will be a problem to run it for a/c and won't be intrusive.

Aircon is Princess factory OEM, not a refit or addition. However it transpires the surveyor has noted the serial number of the generator refers to a manufacture date between 18-24 months later than that of the hull 2010 / reg 2011. So we wonder if something happened to the originally fitted gen and it was replaced. Base spec for the V53/V56 was the 7kw with the 13.5 as an option, we wondered if the replacement was down-specced to the base model 7kw and it would have been 13.5kw originally. Vendor is second owner for the last 3 years and doesn't know about it, so it would have been with original 1st owner.

Anyway, unlikely to be a deal-breaker, just something that got us wondering and something to be mindful of when running power-hungry appliances at anchor.


Thanks again for your input.
 
Am I the only finding odd just 4X120Ah service bats on a 50something foot boat?
Even 40-45ft boats usually have 4X180Ah or 4x200Ah truck batteries.

Am I missing something?

FWIW, I moved from 4X180Ah/12V = 360Ah@24V (tired truck batteries) to
4XTrojan T105RE (6V 225Ah) so 225Ah@24V and all my load/fridge/etc problems are now sorted for good.
They will last up to 1500cycles down to 50%, typical day drops them down to 70-75%.

cheers

V.
 
tom2018 said:
:) thought so, and you are indeed right, the house batteries are 4 x 120ah for 240ah 24 V total before any loss.

Thanks both for your input and clearing that up, genset for a/c will be the MO.

It was your Sq78 build thread, JFM, that inspired me regarding running a/c off batteries anyway.

Genset is in lazarette with the steering gear and passerelle - not the engine room, and anyway given our intended use of day trips mainly with only the occasional overnight, I doubt it will be a problem to run it for a/c and won't be intrusive.

Aircon is Princess factory OEM, not a refit or addition. However it transpires the surveyor has noted the serial number of the generator refers to a manufacture date between 18-24 months later than that of the hull 2010 / reg 2011. So we wonder if something happened to the originally fitted gen and it was replaced. Base spec for the V53/V56 was the 7kw with the 13.5 as an option, we wondered if the replacement was down-specced to the base model 7kw and it would have been 13.5kw originally. Vendor is second owner for the last 3 years and doesn't know about it, so it would have been with original 1st owner.

Anyway, unlikely to be a deal-breaker, just something that got us wondering and something to be mindful of when running power-hungry appliances at anchor.


Thanks again for your input.
Click to expand...

Ask princess for the original build sheet. They are likely to give it to you - will show the original spec and probably serial numbers.

Bear in mind that whilst this is not a major issue it does have hassle factor, and that another buyer will possibly think the same as you which will may have some future impact o its saleability / price.

Good luck.
 
Been looking at our generator amps and I am feeling this will give you greif

At this moment I am pulling 50 amps.

Ac just on. Chargers. People just showered so immersion. Girlfriend has hair dryer on. No cooking yet ...
 
jrudge said:
...

I am feeling this will give you greif

.....
Click to expand...

Tell me about it. I've had to fly back to NZ this week and it's been playing on my mind over and over; my poor surveyor gets 15 emails a day from me rather than a single call.

So the BoM shows the boat left the factory with the 13.5kw gen and all 4 a/c units to include the cockpit. At some point after factory warranty period but still in the 5 year ownership of the 1st owner the gen was replaced (ie not by Princess dealer) with the 7kw one we see in there today. 7kw is factory base-spec for this boat incidentally, the 13.5kw was an option. Second owner has been running the 7kw for their entire 3 year ownership without hassle, however I do know they don't use the boat much - especially at anchor overnight. There is no trace of an insurance claim, no fire or other damage noted, everything in and around the generator space in the lazarette is clean, tidy and "sound as a pound" - surveyor's words. We just don't know why the original failed and why it was replaced with a lesser unit.

We'll have to see how we get on with it for the remainder of the season - if indeed our offer is accepted.

If we do want to upgrade it later then I have been reassured that the 13.5kw will fit back in the space - it did seem like there was some extra to the right of the current gen, it being 5 inches less wide than the 13.5kw unit. Height and depth the same. The surveyor spotted the original fixings on the floor of the lazarette so it could just bolt back in there. Getting it through the lazarette hatch worries me but it obviously logically can be done as someone's removed the 13.5 and put in the 7! Once the housing is off, belts and alternator/genset removed it apparently gets a lot smaller, and the surveyor says a team of two can "jimmy it" (technical term!) to the hatch to be lifted out by just a 350kg load crane, clears the radar arch OK.

How does one go about selling a 960hr 7kw generator though - not the sort of thing you can just put on ebay? Maybe a dealer would offer me trade-in on a new 13.5kw.

Anyway, getting ahead of ourselves - the good news is there's nothing malicious and nobody's trying to hide anything, its just a bit quirky. If we were spending E1m then we'd want to dig further, but we're spending less than half that so my surveyor said I should be prepared to accept some quirks like this. Fair enough.

We may not feel the upgrade to 13.5kw is necessary - there's only one way to find out - buy the boat and USE IT!

I get back next week and we'll hopefully have a decision from the vendor by then, still in time to complete the sale and get some late-season use out of her.


Thanks again for the info
 
tom2018 said:
Tell me about it. I've had to fly back to NZ this week and it's been playing on my mind over and over; my poor surveyor gets 15 emails a day from me rather than a single call.

So the BoM shows the boat left the factory with the 13.5kw gen and all 4 a/c units to include the cockpit. At some point after factory warranty period but still in the 5 year ownership of the 1st owner the gen was replaced (ie not by Princess dealer) with the 7kw one we see in there today. 7kw is factory base-spec for this boat incidentally, the 13.5kw was an option. Second owner has been running the 7kw for their entire 3 year ownership without hassle, however I do know they don't use the boat much - especially at anchor overnight. There is no trace of an insurance claim, no fire or other damage noted, everything in and around the generator space in the lazarette is clean, tidy and "sound as a pound" - surveyor's words. We just don't know why the original failed and why it was replaced with a lesser unit.

We'll have to see how we get on with it for the remainder of the season - if indeed our offer is accepted.

If we do want to upgrade it later then I have been reassured that the 13.5kw will fit back in the space - it did seem like there was some extra to the right of the current gen, it being 5 inches less wide than the 13.5kw unit. Height and depth the same. The surveyor spotted the original fixings on the floor of the lazarette so it could just bolt back in there. Getting it through the lazarette hatch worries me but it obviously logically can be done as someone's removed the 13.5 and put in the 7! Once the housing is off, belts and alternator/genset removed it apparently gets a lot smaller, and the surveyor says a team of two can "jimmy it" (technical term!) to the hatch to be lifted out by just a 350kg load crane, clears the radar arch OK.

How does one go about selling a 960hr 7kw generator though - not the sort of thing you can just put on ebay? Maybe a dealer would offer me trade-in on a new 13.5kw.

Anyway, getting ahead of ourselves - the good news is there's nothing malicious and nobody's trying to hide anything, its just a bit quirky. If we were spending E1m then we'd want to dig further, but we're spending less than half that so my surveyor said I should be prepared to accept some quirks like this. Fair enough.

We may not feel the upgrade to 13.5kw is necessary - there's only one way to find out - buy the boat and USE IT!

I get back next week and we'll hopefully have a decision from the vendor by then, still in time to complete the sale and get some late-season use out of her.


Thanks again for the info
Click to expand...

Any chance of tracking down the first owner and actually just asking him the question?
 
Why not just keep the 7kW genset and be more than happy with it, I wonder?

My previous boat had much larger interiors to cool than a V53, similar appliances etc., and her 6.5kW never struggled to cope with the electrical needs.
Anyone who wants to turn on each and every equipment together without paying any attention could as well stay on shore power 24/7, I reckon… :rolleyes:
 
MapisM said:
Why not just keep the 7kW genset and be more than happy with it, I wonder?

My previous boat had much larger interiors to cool than a V53, similar appliances etc., and her 6.5kW never struggled to cope with the electrical needs.
Anyone who wants to turn on each and every equipment together without paying any attention could as well stay on shore power 24/7, I reckon… :rolleyes:
Click to expand...

P,

Although I agree with your view, don't forget your previous boat doesn't count, you don't use the air con that much (if at all...) on a wooden boat!

Cheers

V

Ps. With 600w solar over two weeks I only turned on the charger for half an hour and it was a rare occasion of two consecutive days of clouds and rain and me staying put.
 
tom2018 said:
Tell me about it. I've had to fly back to NZ this week and it's been playing on my mind over and over; my poor surveyor gets 15 emails a day from me rather than a single call.

So the BoM shows the boat left the factory with the 13.5kw gen and all 4 a/c units to include the cockpit. At some point after factory warranty period but still in the 5 year ownership of the 1st owner the gen was replaced (ie not by Princess dealer) with the 7kw one we see in there today. 7kw is factory base-spec for this boat incidentally, the 13.5kw was an option. Second owner has been running the 7kw for their entire 3 year ownership without hassle, however I do know they don't use the boat much - especially at anchor overnight. There is no trace of an insurance claim, no fire or other damage noted, everything in and around the generator space in the lazarette is clean, tidy and "sound as a pound" - surveyor's words. We just don't know why the original failed and why it was replaced with a lesser unit.

We'll have to see how we get on with it for the remainder of the season - if indeed our offer is accepted.

If we do want to upgrade it later then I have been reassured that the 13.5kw will fit back in the space - it did seem like there was some extra to the right of the current gen, it being 5 inches less wide than the 13.5kw unit. Height and depth the same. The surveyor spotted the original fixings on the floor of the lazarette so it could just bolt back in there. Getting it through the lazarette hatch worries me but it obviously logically can be done as someone's removed the 13.5 and put in the 7! Once the housing is off, belts and alternator/genset removed it apparently gets a lot smaller, and the surveyor says a team of two can "jimmy it" (technical term!) to the hatch to be lifted out by just a 350kg load crane, clears the radar arch OK.

How does one go about selling a 960hr 7kw generator though - not the sort of thing you can just put on ebay? Maybe a dealer would offer me trade-in on a new 13.5kw.

Anyway, getting ahead of ourselves - the good news is there's nothing malicious and nobody's trying to hide anything, its just a bit quirky. If we were spending E1m then we'd want to dig further, but we're spending less than half that so my surveyor said I should be prepared to accept some quirks like this. Fair enough.

We may not feel the upgrade to 13.5kw is necessary - there's only one way to find out - buy the boat and USE IT!

I get back next week and we'll hopefully have a decision from the vendor by then, still in time to complete the sale and get some late-season use out of her.


Thanks again for the info
Click to expand...
A few months back I would have bitten off your right arm just for a chance to take a working genny off your hands.
Someone will want it (badly)
 
jrudge said:
Uk houses have a 60 amp fuse on the main supply as standard. You can ask for an upgrade.

So in KW terms 14kw.

Given most homes dont have Air Con ( I do!) and most heating is gas not electric i would suspect that the average house never comes close to popping the fuse.
Click to expand...

Slightly old data there, they were 60 amps many many years ago and were uprated to 80 or 100 amps many years ago and the current standards are around 100-160 amps depending on property type, so remember this data is only an average based upon a standard 3 bedroom property. In recent years they have hovered around, or just above the 100 amp mark and while this is the case they often fit smaller breakers to limit the current and increase the life of the domestic cabling, so be aware of this curved ball.
 
vas said:
Although I agree with your view, don't forget your previous boat doesn't count, you don't use the air con that much (if at all...) on a wooden boat!
Click to expand...
Agreed, I can already confirm that I'm using a/c more frequently, on the current plastic boat.
Anyway, even if I very rarely used a/c with the old boat (particularly at anchor), the 6.5kW genset did cope with that, even with both the completely independent Westerbeke units running.
And the boat was originally built with a compressor for refilling diving cylinders, go figure...!
The only factor which somewhat reduced the electricity needs compared to most boats was the gas cooktop, but I'd rather have that (and indeed I have it also on the DP) regardless of the genset capacity.
 
tom2018 said:
:) thought so, and you are indeed right, the house batteries are 4 x 120ah for 240ah 24 V total before any loss.

Thanks both for your input and clearing that up, genset for a/c will be the MO.

It was your Sq78 build thread, JFM, that inspired me regarding running a/c off batteries anyway.

Genset is in lazarette with the steering gear and passerelle - not the engine room, and anyway given our intended use of day trips mainly with only the occasional overnight, I doubt it will be a problem to run it for a/c and won't be intrusive.

Aircon is Princess factory OEM, not a refit or addition. However it transpires the surveyor has noted the serial number of the generator refers to a manufacture date between 18-24 months later than that of the hull 2010 / reg 2011. So we wonder if something happened to the originally fitted gen and it was replaced. Base spec for the V53/V56 was the 7kw with the 13.5 as an option, we wondered if the replacement was down-specced to the base model 7kw and it would have been 13.5kw originally. Vendor is second owner for the last 3 years and doesn't know about it, so it would have been with original 1st owner.

Anyway, unlikely to be a deal-breaker, just something that got us wondering and something to be mindful of when running power-hungry appliances at anchor.


Thanks again for your input.
Click to expand...

Do you have the generator serial number, I maybe able to find out know fitted it and why.
 
tom2018 said:
….
View attachment 72833

….
Click to expand...

Interesting to see the old rule of thumb (old world) still seems to work reasonably well today as a guide: ROT compared to data sheet as above:

10,000 BTU/H unit
10,000/3412=2.93 kWth cooling
2.93/3=0.98 kWe
(0.98*1000)/230 = 4.25A compared to 4.6A on data sheet

12,000 BTU/H unit
12,000/3412=3.52 kWth cooling
3.52/3=1.17 kWe
(1.17*1000)/230 = 5.09A compared to 5.4A​

Add a little bit in for fans :encouragement:

We ran two AC units successfully on a HFL 6kVA on my F43, we just used a kettle with small element whilst on the hook, a bit slow but no need to rush......
 
jimmy_the_builder said:
Any chance of tracking down the first owner and actually just asking him the question?
Click to expand...

Surveyor went through all that, first owner just listed as an SCP in Lyon no longer registered. Second owner has no current details of original owner.

ARE said:
Do you have the generator serial number, I maybe able to find out know fitted it and why.
Click to expand...

PM sent with thanks.


John100156 said:
...... no need to rush......
Click to expand...

You said it! Isn't that what this whole boating lark is about? Different pace of life?

Apart from insisting WOT is >35kn? :D



Anyway, I appreciate all the info and help from everyone, after all this it seems we've fallen out with the vendors on inclusion of the tender - boat was presented with the tender but now they want an additional e14-15k for it to be included in the deal. It was a fairly ratty Williams 325 that I noted they didn't flush when we put it back in the garage on the test drive and would have needed a serious service and probably new tubes. This was a private sale so I was dealing direct with the vendor and their agent and didn't have a broker to bat for my side. Bit silly falling out over what is probably only 4% of the mothership's value but the vendor seems not that motivated to come to a deal and sell.

I'll consider it a learning experience however and at least I've made a new best friend - my surveyor - with whom I have spoken to more than my SWMBO over the last few weeks!



The search goes on....

Thanks again
 
tom2018 said:
The search goes on....
Click to expand...

I think we all know what you mean. I had three boats surveyed before I bought my last (F43), I was starting to think the surveyor had a vested interest in finding defects..... Which I suppose is why we employ them after all :cool:

Ironically, I too put an offer in for another boat earlier this week and likewise was £15k adrift, which is a pity, but as you say the search goes on.....!

Best of luck
 
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